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1 <!-- vim: set filetype=docbkxml shiftwidth=2 autoindent expandtab tw=77 : -->
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2
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3 <chapter id="cha:collab">
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4 <title>Collaborating with other people</title>
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5
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6 <para>As a completely decentralised tool, Mercurial doesn't impose
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7 any policy on how people ought to work with each other. However,
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8 if you're new to distributed revision control, it helps to have
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9 some tools and examples in mind when you're thinking about
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10 possible workflow models.</para>
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11
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12 <sect1>
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13 <title>Mercurial's web interface</title>
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14
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15 <para>Mercurial has a powerful web interface that provides several
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16 useful capabilities.</para>
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17
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18 <para>For interactive use, the web interface lets you browse a
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19 single repository or a collection of repositories. You can view
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20 the history of a repository, examine each change (comments and
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21 diffs), and view the contents of each directory and file.</para>
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22
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23 <para>Also for human consumption, the web interface provides an
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24 RSS feed of the changes in a repository. This lets you
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25 <quote>subscribe</quote> to a repository using your favourite
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26 feed reader, and be automatically notified of activity in that
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27 repository as soon as it happens. I find this capability much
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28 more convenient than the model of subscribing to a mailing list
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29 to which notifications are sent, as it requires no additional
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30 configuration on the part of whoever is serving the
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31 repository.</para>
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32
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33 <para>The web interface also lets remote users clone a repository,
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34 pull changes from it, and (when the server is configured to
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35 permit it) push changes back to it. Mercurial's HTTP tunneling
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36 protocol aggressively compresses data, so that it works
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37 efficiently even over low-bandwidth network connections.</para>
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38
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39 <para>The easiest way to get started with the web interface is to
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40 use your web browser to visit an existing repository, such as
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41 the master Mercurial repository at <ulink
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42 url="http://www.selenic.com/repo/hg?style=gitweb">http://www.selenic.com/repo/hg?style=gitweb</ulink>.</para>
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43
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44 <para>If you're interested in providing a web interface to your
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45 own repositories, Mercurial provides two ways to do this. The
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46 first is using the <command role="hg-cmd">hg serve</command>
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47 command, which is best suited to short-term
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48 <quote>lightweight</quote> serving. See section <xref
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49 linkend="sec:collab:serve"/> below for details of how to use
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50 this command. If you have a long-lived repository that you'd
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51 like to make permanently available, Mercurial has built-in
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52 support for the CGI (Common Gateway Interface) standard, which
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53 all common web servers support. See section <xref
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54 linkend="sec:collab:cgi"/> for details of CGI
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55 configuration.</para>
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56
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57 </sect1>
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58 <sect1>
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59 <title>Collaboration models</title>
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60
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61 <para>With a suitably flexible tool, making decisions about
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62 workflow is much more of a social engineering challenge than a
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63 technical one. Mercurial imposes few limitations on how you can
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64 structure the flow of work in a project, so it's up to you and
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65 your group to set up and live with a model that matches your own
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66 particular needs.</para>
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67
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68 <sect2>
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69 <title>Factors to keep in mind</title>
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70
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71 <para>The most important aspect of any model that you must keep
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72 in mind is how well it matches the needs and capabilities of
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73 the people who will be using it. This might seem
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74 self-evident; even so, you still can't afford to forget it for
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75 a moment.</para>
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76
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77 <para>I once put together a workflow model that seemed to make
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78 perfect sense to me, but that caused a considerable amount of
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79 consternation and strife within my development team. In spite
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80 of my attempts to explain why we needed a complex set of
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81 branches, and how changes ought to flow between them, a few
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82 team members revolted. Even though they were smart people,
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83 they didn't want to pay attention to the constraints we were
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84 operating under, or face the consequences of those constraints
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85 in the details of the model that I was advocating.</para>
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86
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87 <para>Don't sweep foreseeable social or technical problems under
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88 the rug. Whatever scheme you put into effect, you should plan
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89 for mistakes and problem scenarios. Consider adding automated
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90 machinery to prevent, or quickly recover from, trouble that
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91 you can anticipate. As an example, if you intend to have a
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92 branch with not-for-release changes in it, you'd do well to
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93 think early about the possibility that someone might
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94 accidentally merge those changes into a release branch. You
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95 could avoid this particular problem by writing a hook that
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96 prevents changes from being merged from an inappropriate
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97 branch.</para>
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98
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99 </sect2>
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100 <sect2>
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101 <title>Informal anarchy</title>
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102
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103 <para>I wouldn't suggest an <quote>anything goes</quote>
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104 approach as something sustainable, but it's a model that's
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105 easy to grasp, and it works perfectly well in a few unusual
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106 situations.</para>
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107
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108 <para>As one example, many projects have a loose-knit group of
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109 collaborators who rarely physically meet each other. Some
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110 groups like to overcome the isolation of working at a distance
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111 by organising occasional <quote>sprints</quote>. In a sprint,
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112 a number of people get together in a single location (a
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113 company's conference room, a hotel meeting room, that kind of
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114 place) and spend several days more or less locked in there,
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115 hacking intensely on a handful of projects.</para>
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116
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117 <para>A sprint is the perfect place to use the <command
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118 role="hg-cmd">hg serve</command> command, since <command
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119 role="hg-cmd">hg serve</command> does not require any fancy
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120 server infrastructure. You can get started with <command
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121 role="hg-cmd">hg serve</command> in moments, by reading
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122 section <xref linkend="sec:collab:serve"/> below. Then simply
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123 tell
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124 the person next to you that you're running a server, send the
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125 URL to them in an instant message, and you immediately have a
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126 quick-turnaround way to work together. They can type your URL
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127 into their web browser and quickly review your changes; or
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128 they can pull a bugfix from you and verify it; or they can
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129 clone a branch containing a new feature and try it out.</para>
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130
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131 <para>The charm, and the problem, with doing things in an ad hoc
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132 fashion like this is that only people who know about your
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133 changes, and where they are, can see them. Such an informal
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134 approach simply doesn't scale beyond a handful people, because
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135 each individual needs to know about $n$ different repositories
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136 to pull from.</para>
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137
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138 </sect2>
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139 <sect2>
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140 <title>A single central repository</title>
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141
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142 <para>For smaller projects migrating from a centralised revision
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143 control tool, perhaps the easiest way to get started is to
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144 have changes flow through a single shared central repository.
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145 This is also the most common <quote>building block</quote> for
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146 more ambitious workflow schemes.</para>
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147
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148 <para>Contributors start by cloning a copy of this repository.
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149 They can pull changes from it whenever they need to, and some
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150 (perhaps all) developers have permission to push a change back
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151 when they're ready for other people to see it.</para>
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152
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153 <para>Under this model, it can still often make sense for people
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154 to pull changes directly from each other, without going
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155 through the central repository. Consider a case in which I
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156 have a tentative bug fix, but I am worried that if I were to
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157 publish it to the central repository, it might subsequently
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158 break everyone else's trees as they pull it. To reduce the
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159 potential for damage, I can ask you to clone my repository
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160 into a temporary repository of your own and test it. This
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161 lets us put off publishing the potentially unsafe change until
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162 it has had a little testing.</para>
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163
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164 <para>In this kind of scenario, people usually use the
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165 <command>ssh</command> protocol to securely push changes to
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166 the central repository, as documented in section <xref
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167 linkend="sec:collab:ssh"/>. It's also
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168 usual to publish a read-only copy of the repository over HTTP
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169 using CGI, as in section <xref linkend="sec:collab:cgi"/>.
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170 Publishing over HTTP
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171 satisfies the needs of people who don't have push access, and
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172 those who want to use web browsers to browse the repository's
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173 history.</para>
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174
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175 </sect2>
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176 <sect2>
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177 <title>Working with multiple branches</title>
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178
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179 <para>Projects of any significant size naturally tend to make
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180 progress on several fronts simultaneously. In the case of
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181 software, it's common for a project to go through periodic
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182 official releases. A release might then go into
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183 <quote>maintenance mode</quote> for a while after its first
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184 publication; maintenance releases tend to contain only bug
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185 fixes, not new features. In parallel with these maintenance
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186 releases, one or more future releases may be under
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187 development. People normally use the word
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188 <quote>branch</quote> to refer to one of these many slightly
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189 different directions in which development is
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190 proceeding.</para>
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191
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192 <para>Mercurial is particularly well suited to managing a number
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193 of simultaneous, but not identical, branches. Each
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194 <quote>development direction</quote> can live in its own
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195 central repository, and you can merge changes from one to
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196 another as the need arises. Because repositories are
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197 independent of each other, unstable changes in a development
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198 branch will never affect a stable branch unless someone
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199 explicitly merges those changes in.</para>
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200
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201 <para>Here's an example of how this can work in practice. Let's
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202 say you have one <quote>main branch</quote> on a central
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203 server.</para>
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204
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205 &interaction.branching.init;
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206
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207 <para>People clone it, make changes locally, test them, and push
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208 them back.</para>
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209
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210 <para>Once the main branch reaches a release milestone, you can
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211 use the <command role="hg-cmd">hg tag</command> command to
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212 give a permanent name to the milestone revision.</para>
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213
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214 &interaction.branching.tag;
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215
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216 <para>Let's say some ongoing
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217 development occurs on the main branch.</para>
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218
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219 &interaction.branching.main;
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220
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221 <para>Using the tag that was recorded at the milestone, people
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222 who clone that repository at any time in the future can use
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223 <command role="hg-cmd">hg update</command> to get a copy of
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224 the working directory exactly as it was when that tagged
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225 revision was committed.</para>
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226
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227 &interaction.branching.update;
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228
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229 <para>In addition, immediately after the main branch is tagged,
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230 someone can then clone the main branch on the server to a new
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231 <quote>stable</quote> branch, also on the server.</para>
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232
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233 &interaction.branching.clone;
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234
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235 <para>Someone who needs to make a change to the stable branch
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236 can then clone <emphasis>that</emphasis> repository, make
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237 their changes, commit, and push their changes back there.</para>
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238
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239 &interaction.branching.stable;
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240
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241 <para>Because Mercurial repositories are independent, and
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242 Mercurial doesn't move changes around automatically, the
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243 stable and main branches are <emphasis>isolated</emphasis>
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244 from each other. The changes that you made on the main branch
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245 don't <quote>leak</quote> to the stable branch, and vice
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246 versa.</para>
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247
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248 <para>You'll often want all of your bugfixes on the stable
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249 branch to show up on the main branch, too. Rather than
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250 rewrite a bugfix on the main branch, you can simply pull and
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251 merge changes from the stable to the main branch, and
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252 Mercurial will bring those bugfixes in for you.</para>
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253
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254 &interaction.branching.merge;
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255
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256 <para>The main branch will still contain changes that are not on
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257 the stable branch, but it will also contain all of the
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258 bugfixes from the stable branch. The stable branch remains
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259 unaffected by these changes.</para>
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260
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261 </sect2>
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262 <sect2>
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263 <title>Feature branches</title>
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264
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265 <para>For larger projects, an effective way to manage change is
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266 to break up a team into smaller groups. Each group has a
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267 shared branch of its own, cloned from a single
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268 <quote>master</quote> branch used by the entire project.
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269 People working on an individual branch are typically quite
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270 isolated from developments on other branches.</para>
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271
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272 <informalfigure id="fig:collab:feature-branches">
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273 <mediaobject><imageobject><imagedata
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274 fileref="feature-branches"/></imageobject><textobject><phrase>XXX
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275 add text</phrase></textobject><caption><para>Feature
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276 branches</para></caption></mediaobject>
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277 </informalfigure>
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278
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279 <para>When a particular feature is deemed to be in suitable
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280 shape, someone on that feature team pulls and merges from the
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281 master branch into the feature branch, then pushes back up to
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282 the master branch.</para>
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283
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284 </sect2>
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285 <sect2>
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286 <title>The release train</title>
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287
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288 <para>Some projects are organised on a <quote>train</quote>
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289 basis: a release is scheduled to happen every few months, and
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290 whatever features are ready when the <quote>train</quote> is
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291 ready to leave are allowed in.</para>
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292
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293 <para>This model resembles working with feature branches. The
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294 difference is that when a feature branch misses a train,
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295 someone on the feature team pulls and merges the changes that
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296 went out on that train release into the feature branch, and
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297 the team continues its work on top of that release so that
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298 their feature can make the next release.</para>
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299
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300 </sect2>
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301 <sect2>
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302 <title>The Linux kernel model</title>
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303
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304 <para>The development of the Linux kernel has a shallow
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305 hierarchical structure, surrounded by a cloud of apparent
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306 chaos. Because most Linux developers use
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307 <command>git</command>, a distributed revision control tool
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308 with capabilities similar to Mercurial, it's useful to
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309 describe the way work flows in that environment; if you like
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310 the ideas, the approach translates well across tools.</para>
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311
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312 <para>At the center of the community sits Linus Torvalds, the
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313 creator of Linux. He publishes a single source repository
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314 that is considered the <quote>authoritative</quote> current
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315 tree by the entire developer community. Anyone can clone
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316 Linus's tree, but he is very choosy about whose trees he pulls
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317 from.</para>
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318
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319 <para>Linus has a number of <quote>trusted lieutenants</quote>.
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320 As a general rule, he pulls whatever changes they publish, in
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321 most cases without even reviewing those changes. Some of
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322 those lieutenants are generally agreed to be
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323 <quote>maintainers</quote>, responsible for specific
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324 subsystems within the kernel. If a random kernel hacker wants
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325 to make a change to a subsystem that they want to end up in
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326 Linus's tree, they must find out who the subsystem's
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327 maintainer is, and ask that maintainer to take their change.
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328 If the maintainer reviews their changes and agrees to take
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329 them, they'll pass them along to Linus in due course.</para>
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330
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331 <para>Individual lieutenants have their own approaches to
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332 reviewing, accepting, and publishing changes; and for deciding
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333 when to feed them to Linus. In addition, there are several
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334 well known branches that people use for different purposes.
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335 For example, a few people maintain <quote>stable</quote>
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336 repositories of older versions of the kernel, to which they
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337 apply critical fixes as needed. Some maintainers publish
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338 multiple trees: one for experimental changes; one for changes
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339 that they are about to feed upstream; and so on. Others just
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340 publish a single tree.</para>
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341
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342 <para>This model has two notable features. The first is that
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343 it's <quote>pull only</quote>. You have to ask, convince, or
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344 beg another developer to take a change from you, because there
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345 are almost no trees to which more than one person can push,
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346 and there's no way to push changes into a tree that someone
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347 else controls.</para>
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348
|
bos@559
|
349 <para>The second is that it's based on reputation and acclaim.
|
bos@559
|
350 If you're an unknown, Linus will probably ignore changes from
|
bos@559
|
351 you without even responding. But a subsystem maintainer will
|
bos@559
|
352 probably review them, and will likely take them if they pass
|
bos@559
|
353 their criteria for suitability. The more <quote>good</quote>
|
bos@559
|
354 changes you contribute to a maintainer, the more likely they
|
bos@559
|
355 are to trust your judgment and accept your changes. If you're
|
bos@559
|
356 well-known and maintain a long-lived branch for something
|
bos@559
|
357 Linus hasn't yet accepted, people with similar interests may
|
bos@559
|
358 pull your changes regularly to keep up with your work.</para>
|
bos@559
|
359
|
bos@559
|
360 <para>Reputation and acclaim don't necessarily cross subsystem
|
bos@559
|
361 or <quote>people</quote> boundaries. If you're a respected
|
bos@559
|
362 but specialised storage hacker, and you try to fix a
|
bos@559
|
363 networking bug, that change will receive a level of scrutiny
|
bos@559
|
364 from a network maintainer comparable to a change from a
|
bos@559
|
365 complete stranger.</para>
|
bos@559
|
366
|
bos@559
|
367 <para>To people who come from more orderly project backgrounds,
|
bos@559
|
368 the comparatively chaotic Linux kernel development process
|
bos@559
|
369 often seems completely insane. It's subject to the whims of
|
bos@559
|
370 individuals; people make sweeping changes whenever they deem
|
bos@559
|
371 it appropriate; and the pace of development is astounding.
|
bos@559
|
372 And yet Linux is a highly successful, well-regarded piece of
|
bos@559
|
373 software.</para>
|
bos@559
|
374
|
bos@559
|
375 </sect2>
|
bos@559
|
376 <sect2>
|
bos@559
|
377 <title>Pull-only versus shared-push collaboration</title>
|
bos@559
|
378
|
bos@559
|
379 <para>A perpetual source of heat in the open source community is
|
bos@559
|
380 whether a development model in which people only ever pull
|
bos@559
|
381 changes from others is <quote>better than</quote> one in which
|
bos@559
|
382 multiple people can push changes to a shared
|
bos@559
|
383 repository.</para>
|
bos@559
|
384
|
bos@559
|
385 <para>Typically, the backers of the shared-push model use tools
|
bos@559
|
386 that actively enforce this approach. If you're using a
|
bos@559
|
387 centralised revision control tool such as Subversion, there's
|
bos@559
|
388 no way to make a choice over which model you'll use: the tool
|
bos@559
|
389 gives you shared-push, and if you want to do anything else,
|
bos@559
|
390 you'll have to roll your own approach on top (such as applying
|
bos@559
|
391 a patch by hand).</para>
|
bos@559
|
392
|
bos@559
|
393 <para>A good distributed revision control tool, such as
|
bos@559
|
394 Mercurial, will support both models. You and your
|
bos@559
|
395 collaborators can then structure how you work together based
|
bos@559
|
396 on your own needs and preferences, not on what contortions
|
bos@559
|
397 your tools force you into.</para>
|
bos@559
|
398
|
bos@559
|
399 </sect2>
|
bos@559
|
400 <sect2>
|
bos@559
|
401 <title>Where collaboration meets branch management</title>
|
bos@559
|
402
|
bos@559
|
403 <para>Once you and your team set up some shared repositories and
|
bos@559
|
404 start propagating changes back and forth between local and
|
bos@559
|
405 shared repos, you begin to face a related, but slightly
|
bos@559
|
406 different challenge: that of managing the multiple directions
|
bos@559
|
407 in which your team may be moving at once. Even though this
|
bos@559
|
408 subject is intimately related to how your team collaborates,
|
bos@559
|
409 it's dense enough to merit treatment of its own, in chapter
|
bos@559
|
410 <xref linkend="chap:branch"/>.</para>
|
bos@559
|
411
|
bos@559
|
412 </sect2>
|
bos@559
|
413 </sect1>
|
bos@559
|
414 <sect1>
|
bos@559
|
415 <title>The technical side of sharing</title>
|
bos@559
|
416
|
bos@559
|
417 <para>The remainder of this chapter is devoted to the question of
|
bos@559
|
418 serving data to your collaborators.</para>
|
bos@559
|
419
|
bos@559
|
420 </sect1>
|
bos@559
|
421 <sect1 id="sec:collab:serve">
|
bos@559
|
422 <title>Informal sharing with <command role="hg-cmd">hg
|
bos@559
|
423 serve</command></title>
|
bos@559
|
424
|
bos@559
|
425 <para>Mercurial's <command role="hg-cmd">hg serve</command>
|
bos@559
|
426 command is wonderfully suited to small, tight-knit, and
|
bos@559
|
427 fast-paced group environments. It also provides a great way to
|
bos@559
|
428 get a feel for using Mercurial commands over a network.</para>
|
bos@559
|
429
|
bos@559
|
430 <para>Run <command role="hg-cmd">hg serve</command> inside a
|
bos@559
|
431 repository, and in under a second it will bring up a specialised
|
bos@559
|
432 HTTP server; this will accept connections from any client, and
|
bos@559
|
433 serve up data for that repository until you terminate it.
|
bos@559
|
434 Anyone who knows the URL of the server you just started, and can
|
bos@559
|
435 talk to your computer over the network, can then use a web
|
bos@559
|
436 browser or Mercurial to read data from that repository. A URL
|
bos@559
|
437 for a <command role="hg-cmd">hg serve</command> instance running
|
bos@559
|
438 on a laptop is likely to look something like
|
bos@559
|
439 <literal>http://my-laptop.local:8000/</literal>.</para>
|
bos@559
|
440
|
bos@559
|
441 <para>The <command role="hg-cmd">hg serve</command> command is
|
bos@559
|
442 <emphasis>not</emphasis> a general-purpose web server. It can do
|
bos@559
|
443 only two things:</para>
|
bos@559
|
444 <itemizedlist>
|
bos@559
|
445 <listitem><para>Allow people to browse the history of the
|
bos@559
|
446 repository it's serving, from their normal web
|
bos@559
|
447 browsers.</para>
|
bos@559
|
448 </listitem>
|
bos@559
|
449 <listitem><para>Speak Mercurial's wire protocol, so that people
|
bos@559
|
450 can <command role="hg-cmd">hg clone</command> or <command
|
bos@559
|
451 role="hg-cmd">hg pull</command> changes from that
|
bos@559
|
452 repository.</para>
|
bos@559
|
453 </listitem></itemizedlist>
|
bos@559
|
454 <para>In particular, <command role="hg-cmd">hg serve</command>
|
bos@559
|
455 won't allow remote users to <emphasis>modify</emphasis> your
|
bos@559
|
456 repository. It's intended for read-only use.</para>
|
bos@559
|
457
|
bos@559
|
458 <para>If you're getting started with Mercurial, there's nothing to
|
bos@559
|
459 prevent you from using <command role="hg-cmd">hg serve</command>
|
bos@559
|
460 to serve up a repository on your own computer, then use commands
|
bos@559
|
461 like <command role="hg-cmd">hg clone</command>, <command
|
bos@559
|
462 role="hg-cmd">hg incoming</command>, and so on to talk to that
|
bos@559
|
463 server as if the repository was hosted remotely. This can help
|
bos@559
|
464 you to quickly get acquainted with using commands on
|
bos@559
|
465 network-hosted repositories.</para>
|
bos@559
|
466
|
bos@559
|
467 <sect2>
|
bos@559
|
468 <title>A few things to keep in mind</title>
|
bos@559
|
469
|
bos@559
|
470 <para>Because it provides unauthenticated read access to all
|
bos@559
|
471 clients, you should only use <command role="hg-cmd">hg
|
bos@559
|
472 serve</command> in an environment where you either don't
|
bos@559
|
473 care, or have complete control over, who can access your
|
bos@559
|
474 network and pull data from your repository.</para>
|
bos@559
|
475
|
bos@559
|
476 <para>The <command role="hg-cmd">hg serve</command> command
|
bos@559
|
477 knows nothing about any firewall software you might have
|
bos@559
|
478 installed on your system or network. It cannot detect or
|
bos@559
|
479 control your firewall software. If other people are unable to
|
bos@559
|
480 talk to a running <command role="hg-cmd">hg serve</command>
|
bos@559
|
481 instance, the second thing you should do
|
bos@559
|
482 (<emphasis>after</emphasis> you make sure that they're using
|
bos@559
|
483 the correct URL) is check your firewall configuration.</para>
|
bos@559
|
484
|
bos@559
|
485 <para>By default, <command role="hg-cmd">hg serve</command>
|
bos@559
|
486 listens for incoming connections on port 8000. If another
|
bos@559
|
487 process is already listening on the port you want to use, you
|
bos@559
|
488 can specify a different port to listen on using the <option
|
bos@559
|
489 role="hg-opt-serve">-p</option> option.</para>
|
bos@559
|
490
|
bos@559
|
491 <para>Normally, when <command role="hg-cmd">hg serve</command>
|
bos@559
|
492 starts, it prints no output, which can be a bit unnerving. If
|
bos@559
|
493 you'd like to confirm that it is indeed running correctly, and
|
bos@559
|
494 find out what URL you should send to your collaborators, start
|
bos@559
|
495 it with the <option role="hg-opt-global">-v</option>
|
bos@559
|
496 option.</para>
|
bos@559
|
497
|
bos@559
|
498 </sect2>
|
bos@559
|
499 </sect1>
|
bos@559
|
500 <sect1 id="sec:collab:ssh">
|
bos@559
|
501 <title>Using the Secure Shell (ssh) protocol</title>
|
bos@559
|
502
|
bos@559
|
503 <para>You can pull and push changes securely over a network
|
bos@559
|
504 connection using the Secure Shell (<literal>ssh</literal>)
|
bos@559
|
505 protocol. To use this successfully, you may have to do a little
|
bos@559
|
506 bit of configuration on the client or server sides.</para>
|
bos@559
|
507
|
bos@559
|
508 <para>If you're not familiar with ssh, it's a network protocol
|
bos@559
|
509 that lets you securely communicate with another computer. To
|
bos@559
|
510 use it with Mercurial, you'll be setting up one or more user
|
bos@559
|
511 accounts on a server so that remote users can log in and execute
|
bos@559
|
512 commands.</para>
|
bos@559
|
513
|
bos@559
|
514 <para>(If you <emphasis>are</emphasis> familiar with ssh, you'll
|
bos@559
|
515 probably find some of the material that follows to be elementary
|
bos@559
|
516 in nature.)</para>
|
bos@559
|
517
|
bos@559
|
518 <sect2>
|
bos@559
|
519 <title>How to read and write ssh URLs</title>
|
bos@559
|
520
|
bos@559
|
521 <para>An ssh URL tends to look like this:</para>
|
bos@559
|
522 <programlisting>ssh://bos@hg.serpentine.com:22/hg/hgbook</programlisting>
|
bos@559
|
523 <orderedlist>
|
bos@559
|
524 <listitem><para>The <quote><literal>ssh://</literal></quote>
|
bos@559
|
525 part tells Mercurial to use the ssh protocol.</para>
|
bos@559
|
526 </listitem>
|
bos@559
|
527 <listitem><para>The <quote><literal>bos@</literal></quote>
|
bos@559
|
528 component indicates what username to log into the server
|
bos@559
|
529 as. You can leave this out if the remote username is the
|
bos@559
|
530 same as your local username.</para>
|
bos@559
|
531 </listitem>
|
bos@559
|
532 <listitem><para>The
|
bos@559
|
533 <quote><literal>hg.serpentine.com</literal></quote> gives
|
bos@559
|
534 the hostname of the server to log into.</para>
|
bos@559
|
535 </listitem>
|
bos@559
|
536 <listitem><para>The <quote>:22</quote> identifies the port
|
bos@559
|
537 number to connect to the server on. The default port is
|
bos@559
|
538 22, so you only need to specify this part if you're
|
bos@559
|
539 <emphasis>not</emphasis> using port 22.</para>
|
bos@559
|
540 </listitem>
|
bos@559
|
541 <listitem><para>The remainder of the URL is the local path to
|
bos@559
|
542 the repository on the server.</para>
|
bos@559
|
543 </listitem></orderedlist>
|
bos@559
|
544
|
bos@559
|
545 <para>There's plenty of scope for confusion with the path
|
bos@559
|
546 component of ssh URLs, as there is no standard way for tools
|
bos@559
|
547 to interpret it. Some programs behave differently than others
|
bos@559
|
548 when dealing with these paths. This isn't an ideal situation,
|
bos@559
|
549 but it's unlikely to change. Please read the following
|
bos@559
|
550 paragraphs carefully.</para>
|
bos@559
|
551
|
bos@559
|
552 <para>Mercurial treats the path to a repository on the server as
|
bos@559
|
553 relative to the remote user's home directory. For example, if
|
bos@559
|
554 user <literal>foo</literal> on the server has a home directory
|
bos@559
|
555 of <filename class="directory">/home/foo</filename>, then an
|
bos@559
|
556 ssh URL that contains a path component of <filename
|
bos@559
|
557 class="directory">bar</filename> <emphasis>really</emphasis>
|
bos@559
|
558 refers to the directory <filename
|
bos@559
|
559 class="directory">/home/foo/bar</filename>.</para>
|
bos@559
|
560
|
bos@559
|
561 <para>If you want to specify a path relative to another user's
|
bos@559
|
562 home directory, you can use a path that starts with a tilde
|
bos@559
|
563 character followed by the user's name (let's call them
|
bos@559
|
564 <literal>otheruser</literal>), like this.</para>
|
bos@559
|
565 <programlisting>ssh://server/~otheruser/hg/repo</programlisting>
|
bos@559
|
566
|
bos@559
|
567 <para>And if you really want to specify an
|
bos@559
|
568 <emphasis>absolute</emphasis> path on the server, begin the
|
bos@559
|
569 path component with two slashes, as in this example.</para>
|
bos@559
|
570 <programlisting>ssh://server//absolute/path</programlisting>
|
bos@559
|
571
|
bos@559
|
572 </sect2>
|
bos@559
|
573 <sect2>
|
bos@559
|
574 <title>Finding an ssh client for your system</title>
|
bos@559
|
575
|
bos@559
|
576 <para>Almost every Unix-like system comes with OpenSSH
|
bos@559
|
577 preinstalled. If you're using such a system, run
|
bos@559
|
578 <literal>which ssh</literal> to find out if the
|
bos@559
|
579 <command>ssh</command> command is installed (it's usually in
|
bos@559
|
580 <filename class="directory">/usr/bin</filename>). In the
|
bos@559
|
581 unlikely event that it isn't present, take a look at your
|
bos@559
|
582 system documentation to figure out how to install it.</para>
|
bos@559
|
583
|
bos@559
|
584 <para>On Windows, you'll first need to download a suitable ssh
|
bos@559
|
585 client. There are two alternatives.</para>
|
bos@559
|
586 <itemizedlist>
|
bos@559
|
587 <listitem><para>Simon Tatham's excellent PuTTY package
|
bos@559
|
588 <citation>web:putty</citation> provides a complete suite
|
bos@559
|
589 of ssh client commands.</para>
|
bos@559
|
590 </listitem>
|
bos@559
|
591 <listitem><para>If you have a high tolerance for pain, you can
|
bos@559
|
592 use the Cygwin port of OpenSSH.</para>
|
bos@559
|
593 </listitem></itemizedlist>
|
bos@559
|
594 <para>In either case, you'll need to edit your \hgini\ file to
|
bos@559
|
595 tell Mercurial where to find the actual client command. For
|
bos@559
|
596 example, if you're using PuTTY, you'll need to use the
|
bos@559
|
597 <command>plink</command> command as a command-line ssh
|
bos@559
|
598 client.</para>
|
bos@559
|
599 <programlisting>[ui] ssh = C:/path/to/plink.exe -ssh -i
|
bos@559
|
600 "C:/path/to/my/private/key"</programlisting>
|
bos@559
|
601
|
bos@559
|
602 <note>
|
bos@559
|
603 <para> The path to <command>plink</command> shouldn't contain
|
bos@559
|
604 any whitespace characters, or Mercurial may not be able to
|
bos@559
|
605 run it correctly (so putting it in <filename
|
bos@559
|
606 class="directory">C:\\Program Files</filename> is probably
|
bos@559
|
607 not a good idea).</para>
|
bos@559
|
608 </note>
|
bos@559
|
609
|
bos@559
|
610 </sect2>
|
bos@559
|
611 <sect2>
|
bos@559
|
612 <title>Generating a key pair</title>
|
bos@559
|
613
|
bos@559
|
614 <para>To avoid the need to repetitively type a password every
|
bos@559
|
615 time you need to use your ssh client, I recommend generating a
|
bos@559
|
616 key pair. On a Unix-like system, the
|
bos@559
|
617 <command>ssh-keygen</command> command will do the trick. On
|
bos@559
|
618 Windows, if you're using PuTTY, the
|
bos@559
|
619 <command>puttygen</command> command is what you'll
|
bos@559
|
620 need.</para>
|
bos@559
|
621
|
bos@559
|
622 <para>When you generate a key pair, it's usually
|
bos@559
|
623 <emphasis>highly</emphasis> advisable to protect it with a
|
bos@559
|
624 passphrase. (The only time that you might not want to do this
|
bos@559
|
625 is when you're using the ssh protocol for automated tasks on a
|
bos@559
|
626 secure network.)</para>
|
bos@559
|
627
|
bos@559
|
628 <para>Simply generating a key pair isn't enough, however.
|
bos@559
|
629 You'll need to add the public key to the set of authorised
|
bos@559
|
630 keys for whatever user you're logging in remotely as. For
|
bos@559
|
631 servers using OpenSSH (the vast majority), this will mean
|
bos@559
|
632 adding the public key to a list in a file called <filename
|
bos@559
|
633 role="special">authorized_keys</filename> in their <filename
|
bos@559
|
634 role="special" class="directory">.ssh</filename>
|
bos@559
|
635 directory.</para>
|
bos@559
|
636
|
bos@559
|
637 <para>On a Unix-like system, your public key will have a
|
bos@559
|
638 <filename>.pub</filename> extension. If you're using
|
bos@559
|
639 <command>puttygen</command> on Windows, you can save the
|
bos@559
|
640 public key to a file of your choosing, or paste it from the
|
bos@559
|
641 window it's displayed in straight into the <filename
|
bos@559
|
642 role="special">authorized_keys</filename> file.</para>
|
bos@559
|
643
|
bos@559
|
644 </sect2>
|
bos@559
|
645 <sect2>
|
bos@559
|
646 <title>Using an authentication agent</title>
|
bos@559
|
647
|
bos@559
|
648 <para>An authentication agent is a daemon that stores
|
bos@559
|
649 passphrases in memory (so it will forget passphrases if you
|
bos@559
|
650 log out and log back in again). An ssh client will notice if
|
bos@559
|
651 it's running, and query it for a passphrase. If there's no
|
bos@559
|
652 authentication agent running, or the agent doesn't store the
|
bos@559
|
653 necessary passphrase, you'll have to type your passphrase
|
bos@559
|
654 every time Mercurial tries to communicate with a server on
|
bos@559
|
655 your behalf (e.g. whenever you pull or push changes).</para>
|
bos@559
|
656
|
bos@559
|
657 <para>The downside of storing passphrases in an agent is that
|
bos@559
|
658 it's possible for a well-prepared attacker to recover the
|
bos@559
|
659 plain text of your passphrases, in some cases even if your
|
bos@559
|
660 system has been power-cycled. You should make your own
|
bos@559
|
661 judgment as to whether this is an acceptable risk. It
|
bos@559
|
662 certainly saves a lot of repeated typing.</para>
|
bos@559
|
663
|
bos@559
|
664 <para>On Unix-like systems, the agent is called
|
bos@559
|
665 <command>ssh-agent</command>, and it's often run automatically
|
bos@559
|
666 for you when you log in. You'll need to use the
|
bos@559
|
667 <command>ssh-add</command> command to add passphrases to the
|
bos@559
|
668 agent's store. On Windows, if you're using PuTTY, the
|
bos@559
|
669 <command>pageant</command> command acts as the agent. It adds
|
bos@559
|
670 an icon to your system tray that will let you manage stored
|
bos@559
|
671 passphrases.</para>
|
bos@559
|
672
|
bos@559
|
673 </sect2>
|
bos@559
|
674 <sect2>
|
bos@559
|
675 <title>Configuring the server side properly</title>
|
bos@559
|
676
|
bos@559
|
677 <para>Because ssh can be fiddly to set up if you're new to it,
|
bos@559
|
678 there's a variety of things that can go wrong. Add Mercurial
|
bos@559
|
679 on top, and there's plenty more scope for head-scratching.
|
bos@559
|
680 Most of these potential problems occur on the server side, not
|
bos@559
|
681 the client side. The good news is that once you've gotten a
|
bos@559
|
682 configuration working, it will usually continue to work
|
bos@559
|
683 indefinitely.</para>
|
bos@559
|
684
|
bos@559
|
685 <para>Before you try using Mercurial to talk to an ssh server,
|
bos@559
|
686 it's best to make sure that you can use the normal
|
bos@559
|
687 <command>ssh</command> or <command>putty</command> command to
|
bos@559
|
688 talk to the server first. If you run into problems with using
|
bos@559
|
689 these commands directly, Mercurial surely won't work. Worse,
|
bos@559
|
690 it will obscure the underlying problem. Any time you want to
|
bos@559
|
691 debug ssh-related Mercurial problems, you should drop back to
|
bos@559
|
692 making sure that plain ssh client commands work first,
|
bos@559
|
693 <emphasis>before</emphasis> you worry about whether there's a
|
bos@559
|
694 problem with Mercurial.</para>
|
bos@559
|
695
|
bos@559
|
696 <para>The first thing to be sure of on the server side is that
|
bos@559
|
697 you can actually log in from another machine at all. If you
|
bos@559
|
698 can't use <command>ssh</command> or <command>putty</command>
|
bos@559
|
699 to log in, the error message you get may give you a few hints
|
bos@559
|
700 as to what's wrong. The most common problems are as
|
bos@559
|
701 follows.</para>
|
bos@559
|
702 <itemizedlist>
|
bos@559
|
703 <listitem><para>If you get a <quote>connection refused</quote>
|
bos@559
|
704 error, either there isn't an SSH daemon running on the
|
bos@559
|
705 server at all, or it's inaccessible due to firewall
|
bos@559
|
706 configuration.</para>
|
bos@559
|
707 </listitem>
|
bos@559
|
708 <listitem><para>If you get a <quote>no route to host</quote>
|
bos@559
|
709 error, you either have an incorrect address for the server
|
bos@559
|
710 or a seriously locked down firewall that won't admit its
|
bos@559
|
711 existence at all.</para>
|
bos@559
|
712 </listitem>
|
bos@559
|
713 <listitem><para>If you get a <quote>permission denied</quote>
|
bos@559
|
714 error, you may have mistyped the username on the server,
|
bos@559
|
715 or you could have mistyped your key's passphrase or the
|
bos@559
|
716 remote user's password.</para>
|
bos@559
|
717 </listitem></itemizedlist>
|
bos@559
|
718 <para>In summary, if you're having trouble talking to the
|
bos@559
|
719 server's ssh daemon, first make sure that one is running at
|
bos@559
|
720 all. On many systems it will be installed, but disabled, by
|
bos@559
|
721 default. Once you're done with this step, you should then
|
bos@559
|
722 check that the server's firewall is configured to allow
|
bos@559
|
723 incoming connections on the port the ssh daemon is listening
|
bos@559
|
724 on (usually 22). Don't worry about more exotic possibilities
|
bos@559
|
725 for misconfiguration until you've checked these two
|
bos@559
|
726 first.</para>
|
bos@559
|
727
|
bos@559
|
728 <para>If you're using an authentication agent on the client side
|
bos@559
|
729 to store passphrases for your keys, you ought to be able to
|
bos@559
|
730 log into the server without being prompted for a passphrase or
|
bos@559
|
731 a password. If you're prompted for a passphrase, there are a
|
bos@559
|
732 few possible culprits.</para>
|
bos@559
|
733 <itemizedlist>
|
bos@559
|
734 <listitem><para>You might have forgotten to use
|
bos@559
|
735 <command>ssh-add</command> or <command>pageant</command>
|
bos@559
|
736 to store the passphrase.</para>
|
bos@559
|
737 </listitem>
|
bos@559
|
738 <listitem><para>You might have stored the passphrase for the
|
bos@559
|
739 wrong key.</para>
|
bos@559
|
740 </listitem></itemizedlist>
|
bos@559
|
741 <para>If you're being prompted for the remote user's password,
|
bos@559
|
742 there are another few possible problems to check.</para>
|
bos@559
|
743 <itemizedlist>
|
bos@559
|
744 <listitem><para>Either the user's home directory or their
|
bos@559
|
745 <filename role="special" class="directory">.ssh</filename>
|
bos@559
|
746 directory might have excessively liberal permissions. As
|
bos@559
|
747 a result, the ssh daemon will not trust or read their
|
bos@559
|
748 <filename role="special">authorized_keys</filename> file.
|
bos@559
|
749 For example, a group-writable home or <filename
|
bos@559
|
750 role="special" class="directory">.ssh</filename>
|
bos@559
|
751 directory will often cause this symptom.</para>
|
bos@559
|
752 </listitem>
|
bos@559
|
753 <listitem><para>The user's <filename
|
bos@559
|
754 role="special">authorized_keys</filename> file may have
|
bos@559
|
755 a problem. If anyone other than the user owns or can write
|
bos@559
|
756 to that file, the ssh daemon will not trust or read
|
bos@559
|
757 it.</para>
|
bos@559
|
758 </listitem></itemizedlist>
|
bos@559
|
759
|
bos@559
|
760 <para>In the ideal world, you should be able to run the
|
bos@559
|
761 following command successfully, and it should print exactly
|
bos@559
|
762 one line of output, the current date and time.</para>
|
bos@559
|
763 <programlisting>ssh myserver date</programlisting>
|
bos@559
|
764
|
bos@559
|
765 <para>If, on your server, you have login scripts that print
|
bos@559
|
766 banners or other junk even when running non-interactive
|
bos@559
|
767 commands like this, you should fix them before you continue,
|
bos@559
|
768 so that they only print output if they're run interactively.
|
bos@559
|
769 Otherwise these banners will at least clutter up Mercurial's
|
bos@559
|
770 output. Worse, they could potentially cause problems with
|
bos@559
|
771 running Mercurial commands remotely. Mercurial makes tries to
|
bos@559
|
772 detect and ignore banners in non-interactive
|
bos@559
|
773 <command>ssh</command> sessions, but it is not foolproof. (If
|
bos@559
|
774 you're editing your login scripts on your server, the usual
|
bos@559
|
775 way to see if a login script is running in an interactive
|
bos@559
|
776 shell is to check the return code from the command
|
bos@559
|
777 <literal>tty -s</literal>.)</para>
|
bos@559
|
778
|
bos@559
|
779 <para>Once you've verified that plain old ssh is working with
|
bos@559
|
780 your server, the next step is to ensure that Mercurial runs on
|
bos@559
|
781 the server. The following command should run
|
bos@559
|
782 successfully:</para>
|
bos@559
|
783 <programlisting>ssh myserver hg version</programlisting>
|
bos@559
|
784 <para>If you see an error message instead of normal <command
|
bos@559
|
785 role="hg-cmd">hg version</command> output, this is usually
|
bos@559
|
786 because you haven't installed Mercurial to <filename
|
bos@559
|
787 class="directory">/usr/bin</filename>. Don't worry if this
|
bos@559
|
788 is the case; you don't need to do that. But you should check
|
bos@559
|
789 for a few possible problems.</para>
|
bos@559
|
790 <itemizedlist>
|
bos@559
|
791 <listitem><para>Is Mercurial really installed on the server at
|
bos@559
|
792 all? I know this sounds trivial, but it's worth
|
bos@559
|
793 checking!</para>
|
bos@559
|
794 </listitem>
|
bos@559
|
795 <listitem><para>Maybe your shell's search path (usually set
|
bos@559
|
796 via the <envar>PATH</envar> environment variable) is
|
bos@559
|
797 simply misconfigured.</para>
|
bos@559
|
798 </listitem>
|
bos@559
|
799 <listitem><para>Perhaps your <envar>PATH</envar> environment
|
bos@559
|
800 variable is only being set to point to the location of the
|
bos@559
|
801 <command>hg</command> executable if the login session is
|
bos@559
|
802 interactive. This can happen if you're setting the path
|
bos@559
|
803 in the wrong shell login script. See your shell's
|
bos@559
|
804 documentation for details.</para>
|
bos@559
|
805 </listitem>
|
bos@559
|
806 <listitem><para>The <envar>PYTHONPATH</envar> environment
|
bos@559
|
807 variable may need to contain the path to the Mercurial
|
bos@559
|
808 Python modules. It might not be set at all; it could be
|
bos@559
|
809 incorrect; or it may be set only if the login is
|
bos@559
|
810 interactive.</para>
|
bos@559
|
811 </listitem></itemizedlist>
|
bos@559
|
812
|
bos@559
|
813 <para>If you can run <command role="hg-cmd">hg version</command>
|
bos@559
|
814 over an ssh connection, well done! You've got the server and
|
bos@559
|
815 client sorted out. You should now be able to use Mercurial to
|
bos@559
|
816 access repositories hosted by that username on that server.
|
bos@559
|
817 If you run into problems with Mercurial and ssh at this point,
|
bos@559
|
818 try using the <option role="hg-opt-global">--debug</option>
|
bos@559
|
819 option to get a clearer picture of what's going on.</para>
|
bos@559
|
820
|
bos@559
|
821 </sect2>
|
bos@559
|
822 <sect2>
|
bos@559
|
823 <title>Using compression with ssh</title>
|
bos@559
|
824
|
bos@559
|
825 <para>Mercurial does not compress data when it uses the ssh
|
bos@559
|
826 protocol, because the ssh protocol can transparently compress
|
bos@559
|
827 data. However, the default behaviour of ssh clients is
|
bos@559
|
828 <emphasis>not</emphasis> to request compression.</para>
|
bos@559
|
829
|
bos@559
|
830 <para>Over any network other than a fast LAN (even a wireless
|
bos@559
|
831 network), using compression is likely to significantly speed
|
bos@559
|
832 up Mercurial's network operations. For example, over a WAN,
|
bos@559
|
833 someone measured compression as reducing the amount of time
|
bos@559
|
834 required to clone a particularly large repository from 51
|
bos@559
|
835 minutes to 17 minutes.</para>
|
bos@559
|
836
|
bos@559
|
837 <para>Both <command>ssh</command> and <command>plink</command>
|
bos@559
|
838 accept a <option role="cmd-opt-ssh">-C</option> option which
|
bos@559
|
839 turns on compression. You can easily edit your <filename
|
bos@559
|
840 role="special"> /.hgrc</filename>\ to enable compression for
|
bos@559
|
841 all of Mercurial's uses of the ssh protocol.</para>
|
bos@559
|
842 <programlisting>[ui] ssh = ssh -C</programlisting>
|
bos@559
|
843
|
bos@559
|
844 <para>If you use <command>ssh</command>, you can configure it to
|
bos@559
|
845 always use compression when talking to your server. To do
|
bos@559
|
846 this, edit your <filename
|
bos@559
|
847 role="special">.ssh/config</filename> file (which may not
|
bos@559
|
848 yet exist), as follows.</para>
|
bos@559
|
849 <programlisting>Host hg Compression yes HostName
|
bos@559
|
850 hg.example.com</programlisting>
|
bos@559
|
851 <para>This defines an alias, <literal>hg</literal>. When you
|
bos@559
|
852 use it on the <command>ssh</command> command line or in a
|
bos@559
|
853 Mercurial <literal>ssh</literal>-protocol URL, it will cause
|
bos@559
|
854 <command>ssh</command> to connect to
|
bos@559
|
855 <literal>hg.example.com</literal> and use compression. This
|
bos@559
|
856 gives you both a shorter name to type and compression, each of
|
bos@559
|
857 which is a good thing in its own right.</para>
|
bos@559
|
858
|
bos@559
|
859 </sect2>
|
bos@559
|
860 </sect1>
|
bos@559
|
861 <sect1 id="sec:collab:cgi">
|
bos@559
|
862 <title>Serving over HTTP using CGI</title>
|
bos@559
|
863
|
bos@559
|
864 <para>Depending on how ambitious you are, configuring Mercurial's
|
bos@559
|
865 CGI interface can take anything from a few moments to several
|
bos@559
|
866 hours.</para>
|
bos@559
|
867
|
bos@559
|
868 <para>We'll begin with the simplest of examples, and work our way
|
bos@559
|
869 towards a more complex configuration. Even for the most basic
|
bos@559
|
870 case, you're almost certainly going to need to read and modify
|
bos@559
|
871 your web server's configuration.</para>
|
bos@559
|
872
|
bos@559
|
873 <note>
|
bos@559
|
874 <para> Configuring a web server is a complex, fiddly, and
|
bos@559
|
875 highly system-dependent activity. I can't possibly give you
|
bos@559
|
876 instructions that will cover anything like all of the cases
|
bos@559
|
877 you will encounter. Please use your discretion and judgment in
|
bos@559
|
878 following the sections below. Be prepared to make plenty of
|
bos@559
|
879 mistakes, and to spend a lot of time reading your server's
|
bos@559
|
880 error logs.</para>
|
bos@559
|
881 </note>
|
bos@559
|
882
|
bos@559
|
883 <sect2>
|
bos@559
|
884 <title>Web server configuration checklist</title>
|
bos@559
|
885
|
bos@559
|
886 <para>Before you continue, do take a few moments to check a few
|
bos@559
|
887 aspects of your system's setup.</para>
|
bos@559
|
888
|
bos@559
|
889 <orderedlist>
|
bos@559
|
890 <listitem><para>Do you have a web server installed at all?
|
bos@559
|
891 Mac OS X ships with Apache, but many other systems may not
|
bos@559
|
892 have a web server installed.</para>
|
bos@559
|
893 </listitem>
|
bos@559
|
894 <listitem><para>If you have a web server installed, is it
|
bos@559
|
895 actually running? On most systems, even if one is
|
bos@559
|
896 present, it will be disabled by default.</para>
|
bos@559
|
897 </listitem>
|
bos@559
|
898 <listitem><para>Is your server configured to allow you to run
|
bos@559
|
899 CGI programs in the directory where you plan to do so?
|
bos@559
|
900 Most servers default to explicitly disabling the ability
|
bos@559
|
901 to run CGI programs.</para>
|
bos@559
|
902 </listitem></orderedlist>
|
bos@559
|
903
|
bos@559
|
904 <para>If you don't have a web server installed, and don't have
|
bos@559
|
905 substantial experience configuring Apache, you should consider
|
bos@559
|
906 using the <literal>lighttpd</literal> web server instead of
|
bos@559
|
907 Apache. Apache has a well-deserved reputation for baroque and
|
bos@559
|
908 confusing configuration. While <literal>lighttpd</literal> is
|
bos@559
|
909 less capable in some ways than Apache, most of these
|
bos@559
|
910 capabilities are not relevant to serving Mercurial
|
bos@559
|
911 repositories. And <literal>lighttpd</literal> is undeniably
|
bos@559
|
912 <emphasis>much</emphasis> easier to get started with than
|
bos@559
|
913 Apache.</para>
|
bos@559
|
914
|
bos@559
|
915 </sect2>
|
bos@559
|
916 <sect2>
|
bos@559
|
917 <title>Basic CGI configuration</title>
|
bos@559
|
918
|
bos@559
|
919 <para>On Unix-like systems, it's common for users to have a
|
bos@559
|
920 subdirectory named something like <filename
|
bos@559
|
921 class="directory">public_html</filename> in their home
|
bos@559
|
922 directory, from which they can serve up web pages. A file
|
bos@559
|
923 named <filename>foo</filename> in this directory will be
|
bos@559
|
924 accessible at a URL of the form
|
bos@559
|
925 <literal>http://www.example.com/\
|
bos@559
|
926 {</literal>username/foo}.</para>
|
bos@559
|
927
|
bos@559
|
928 <para>To get started, find the <filename
|
bos@559
|
929 role="special">hgweb.cgi</filename> script that should be
|
bos@559
|
930 present in your Mercurial installation. If you can't quickly
|
bos@559
|
931 find a local copy on your system, simply download one from the
|
bos@559
|
932 master Mercurial repository at <ulink
|
bos@559
|
933 url="http://www.selenic.com/repo/hg/raw-file/tip/hgweb.cgi">http://www.selenic.com/repo/hg/raw-file/tip/hgweb.cgi</ulink>.</para>
|
bos@559
|
934
|
bos@559
|
935 <para>You'll need to copy this script into your <filename
|
bos@559
|
936 class="directory">public_html</filename> directory, and
|
bos@559
|
937 ensure that it's executable.</para>
|
bos@559
|
938 <programlisting>cp .../hgweb.cgi ~/public_html chmod 755
|
bos@559
|
939 ~/public_html/hgweb.cgi</programlisting>
|
bos@559
|
940 <para>The <literal>755</literal> argument to
|
bos@559
|
941 <command>chmod</command> is a little more general than just
|
bos@559
|
942 making the script executable: it ensures that the script is
|
bos@559
|
943 executable by anyone, and that <quote>group</quote> and
|
bos@559
|
944 <quote>other</quote> write permissions are
|
bos@559
|
945 <emphasis>not</emphasis> set. If you were to leave those
|
bos@559
|
946 write permissions enabled, Apache's <literal>suexec</literal>
|
bos@559
|
947 subsystem would likely refuse to execute the script. In fact,
|
bos@559
|
948 <literal>suexec</literal> also insists that the
|
bos@559
|
949 <emphasis>directory</emphasis> in which the script resides
|
bos@559
|
950 must not be writable by others.</para>
|
bos@559
|
951 <programlisting>chmod 755 ~/public_html</programlisting>
|
bos@559
|
952
|
bos@559
|
953 <sect3 id="sec:collab:wtf">
|
bos@559
|
954 <title>What could <emphasis>possibly</emphasis> go
|
bos@559
|
955 wrong?</title>
|
bos@559
|
956
|
bos@559
|
957 <para>Once you've copied the CGI script into place, go into a
|
bos@559
|
958 web browser, and try to open the URL <ulink
|
bos@559
|
959 url="http://myhostname/
|
bos@559
|
960 myuser/hgweb.cgi">http://myhostname/
|
bos@559
|
961 myuser/hgweb.cgi</ulink>, <emphasis>but</emphasis> brace
|
bos@559
|
962 yourself for instant failure. There's a high probability
|
bos@559
|
963 that trying to visit this URL will fail, and there are many
|
bos@559
|
964 possible reasons for this. In fact, you're likely to
|
bos@559
|
965 stumble over almost every one of the possible errors below,
|
bos@559
|
966 so please read carefully. The following are all of the
|
bos@559
|
967 problems I ran into on a system running Fedora 7, with a
|
bos@559
|
968 fresh installation of Apache, and a user account that I
|
bos@559
|
969 created specially to perform this exercise.</para>
|
bos@559
|
970
|
bos@559
|
971 <para>Your web server may have per-user directories disabled.
|
bos@559
|
972 If you're using Apache, search your config file for a
|
bos@559
|
973 <literal>UserDir</literal> directive. If there's none
|
bos@559
|
974 present, per-user directories will be disabled. If one
|
bos@559
|
975 exists, but its value is <literal>disabled</literal>, then
|
bos@559
|
976 per-user directories will be disabled. Otherwise, the
|
bos@559
|
977 string after <literal>UserDir</literal> gives the name of
|
bos@559
|
978 the subdirectory that Apache will look in under your home
|
bos@559
|
979 directory, for example <filename
|
bos@559
|
980 class="directory">public_html</filename>.</para>
|
bos@559
|
981
|
bos@559
|
982 <para>Your file access permissions may be too restrictive.
|
bos@559
|
983 The web server must be able to traverse your home directory
|
bos@559
|
984 and directories under your <filename
|
bos@559
|
985 class="directory">public_html</filename> directory, and
|
bos@559
|
986 read files under the latter too. Here's a quick recipe to
|
bos@559
|
987 help you to make your permissions more appropriate.</para>
|
bos@559
|
988 <programlisting>chmod 755 ~ find ~/public_html -type d -print0
|
bos@559
|
989 | xargs -0r chmod 755 find ~/public_html -type f -print0 |
|
bos@559
|
990 xargs -0r chmod 644</programlisting>
|
bos@559
|
991
|
bos@559
|
992 <para>The other possibility with permissions is that you might
|
bos@559
|
993 get a completely empty window when you try to load the
|
bos@559
|
994 script. In this case, it's likely that your access
|
ori@561
|
995 permissions are <emphasis>too permissive</emphasis>. Apache's
|
bos@559
|
996 <literal>suexec</literal> subsystem won't execute a script
|
bos@559
|
997 that's group- or world-writable, for example.</para>
|
bos@559
|
998
|
bos@559
|
999 <para>Your web server may be configured to disallow execution
|
bos@559
|
1000 of CGI programs in your per-user web directory. Here's
|
bos@559
|
1001 Apache's default per-user configuration from my Fedora
|
bos@559
|
1002 system.</para>
|
bos@559
|
1003 <programlisting><Directory /home/*/public_html>
|
bos@559
|
1004 AllowOverride FileInfo AuthConfig Limit Options MultiViews
|
bos@559
|
1005 Indexes SymLinksIfOwnerMatch IncludesNoExec <Limit GET
|
bos@559
|
1006 POST OPTIONS> Order allow,deny Allow from all
|
bos@559
|
1007 </Limit> <LimitExcept GET POST OPTIONS> Order
|
bos@559
|
1008 deny,allow Deny from all </LimitExcept>
|
bos@559
|
1009 </Directory></programlisting>
|
bos@559
|
1010 <para>If you find a similar-looking
|
bos@559
|
1011 <literal>Directory</literal> group in your Apache
|
bos@559
|
1012 configuration, the directive to look at inside it is
|
bos@559
|
1013 <literal>Options</literal>. Add <literal>ExecCGI</literal>
|
bos@559
|
1014 to the end of this list if it's missing, and restart the web
|
bos@559
|
1015 server.</para>
|
bos@559
|
1016
|
bos@559
|
1017 <para>If you find that Apache serves you the text of the CGI
|
bos@559
|
1018 script instead of executing it, you may need to either
|
bos@559
|
1019 uncomment (if already present) or add a directive like
|
bos@559
|
1020 this.</para>
|
bos@559
|
1021 <programlisting>AddHandler cgi-script .cgi</programlisting>
|
bos@559
|
1022
|
bos@559
|
1023 <para>The next possibility is that you might be served with a
|
bos@559
|
1024 colourful Python backtrace claiming that it can't import a
|
bos@559
|
1025 <literal>mercurial</literal>-related module. This is
|
bos@559
|
1026 actually progress! The server is now capable of executing
|
bos@559
|
1027 your CGI script. This error is only likely to occur if
|
bos@559
|
1028 you're running a private installation of Mercurial, instead
|
bos@559
|
1029 of a system-wide version. Remember that the web server runs
|
bos@559
|
1030 the CGI program without any of the environment variables
|
bos@559
|
1031 that you take for granted in an interactive session. If
|
bos@559
|
1032 this error happens to you, edit your copy of <filename
|
bos@559
|
1033 role="special">hgweb.cgi</filename> and follow the
|
bos@559
|
1034 directions inside it to correctly set your
|
bos@559
|
1035 <envar>PYTHONPATH</envar> environment variable.</para>
|
bos@559
|
1036
|
bos@559
|
1037 <para>Finally, you are <emphasis>certain</emphasis> to by
|
bos@559
|
1038 served with another colourful Python backtrace: this one
|
bos@559
|
1039 will complain that it can't find <filename
|
bos@559
|
1040 class="directory">/path/to/repository</filename>. Edit
|
bos@559
|
1041 your <filename role="special">hgweb.cgi</filename> script
|
bos@559
|
1042 and replace the <filename
|
bos@559
|
1043 class="directory">/path/to/repository</filename> string
|
bos@559
|
1044 with the complete path to the repository you want to serve
|
bos@559
|
1045 up.</para>
|
bos@559
|
1046
|
bos@559
|
1047 <para>At this point, when you try to reload the page, you
|
bos@559
|
1048 should be presented with a nice HTML view of your
|
bos@559
|
1049 repository's history. Whew!</para>
|
bos@559
|
1050
|
bos@559
|
1051 </sect3>
|
bos@559
|
1052 <sect3>
|
bos@559
|
1053 <title>Configuring lighttpd</title>
|
bos@559
|
1054
|
bos@559
|
1055 <para>To be exhaustive in my experiments, I tried configuring
|
bos@559
|
1056 the increasingly popular <literal>lighttpd</literal> web
|
bos@559
|
1057 server to serve the same repository as I described with
|
bos@559
|
1058 Apache above. I had already overcome all of the problems I
|
bos@559
|
1059 outlined with Apache, many of which are not server-specific.
|
bos@559
|
1060 As a result, I was fairly sure that my file and directory
|
bos@559
|
1061 permissions were good, and that my <filename
|
bos@559
|
1062 role="special">hgweb.cgi</filename> script was properly
|
bos@559
|
1063 edited.</para>
|
bos@559
|
1064
|
bos@559
|
1065 <para>Once I had Apache running, getting
|
bos@559
|
1066 <literal>lighttpd</literal> to serve the repository was a
|
bos@559
|
1067 snap (in other words, even if you're trying to use
|
bos@559
|
1068 <literal>lighttpd</literal>, you should read the Apache
|
bos@559
|
1069 section). I first had to edit the
|
bos@559
|
1070 <literal>mod_access</literal> section of its config file to
|
bos@559
|
1071 enable <literal>mod_cgi</literal> and
|
bos@559
|
1072 <literal>mod_userdir</literal>, both of which were disabled
|
bos@559
|
1073 by default on my system. I then added a few lines to the
|
bos@559
|
1074 end of the config file, to configure these modules.</para>
|
bos@559
|
1075 <programlisting>userdir.path = "public_html" cgi.assign = (
|
bos@559
|
1076 ".cgi" => "" )</programlisting>
|
bos@559
|
1077 <para>With this done, <literal>lighttpd</literal> ran
|
bos@559
|
1078 immediately for me. If I had configured
|
bos@559
|
1079 <literal>lighttpd</literal> before Apache, I'd almost
|
bos@559
|
1080 certainly have run into many of the same system-level
|
bos@559
|
1081 configuration problems as I did with Apache. However, I
|
bos@559
|
1082 found <literal>lighttpd</literal> to be noticeably easier to
|
bos@559
|
1083 configure than Apache, even though I've used Apache for over
|
bos@559
|
1084 a decade, and this was my first exposure to
|
bos@559
|
1085 <literal>lighttpd</literal>.</para>
|
bos@559
|
1086
|
bos@559
|
1087 </sect3>
|
bos@559
|
1088 </sect2>
|
bos@559
|
1089 <sect2>
|
bos@559
|
1090 <title>Sharing multiple repositories with one CGI script</title>
|
bos@559
|
1091
|
bos@559
|
1092 <para>The <filename role="special">hgweb.cgi</filename> script
|
bos@559
|
1093 only lets you publish a single repository, which is an
|
bos@559
|
1094 annoying restriction. If you want to publish more than one
|
bos@559
|
1095 without wracking yourself with multiple copies of the same
|
bos@559
|
1096 script, each with different names, a better choice is to use
|
bos@559
|
1097 the <filename role="special">hgwebdir.cgi</filename>
|
bos@559
|
1098 script.</para>
|
bos@559
|
1099
|
bos@559
|
1100 <para>The procedure to configure <filename
|
bos@559
|
1101 role="special">hgwebdir.cgi</filename> is only a little more
|
bos@559
|
1102 involved than for <filename
|
bos@559
|
1103 role="special">hgweb.cgi</filename>. First, you must obtain
|
bos@559
|
1104 a copy of the script. If you don't have one handy, you can
|
bos@559
|
1105 download a copy from the master Mercurial repository at <ulink
|
bos@559
|
1106 url="http://www.selenic.com/repo/hg/raw-file/tip/hgwebdir.cgi">http://www.selenic.com/repo/hg/raw-file/tip/hgwebdir.cgi</ulink>.</para>
|
bos@559
|
1107
|
bos@559
|
1108 <para>You'll need to copy this script into your <filename
|
bos@559
|
1109 class="directory">public_html</filename> directory, and
|
bos@559
|
1110 ensure that it's executable.</para>
|
bos@559
|
1111 <programlisting>cp .../hgwebdir.cgi ~/public_html chmod 755
|
bos@559
|
1112 ~/public_html ~/public_html/hgwebdir.cgi</programlisting>
|
bos@559
|
1113 <para>With basic configuration out of the way, try to visit
|
bos@559
|
1114 <ulink url="http://myhostname/
|
bos@559
|
1115 myuser/hgwebdir.cgi">http://myhostname/
|
bos@559
|
1116 myuser/hgwebdir.cgi</ulink> in your browser. It should
|
bos@559
|
1117 display an empty list of repositories. If you get a blank
|
bos@559
|
1118 window or error message, try walking through the list of
|
bos@559
|
1119 potential problems in section <xref
|
bos@559
|
1120 linkend="sec:collab:wtf"/>.</para>
|
bos@559
|
1121
|
bos@559
|
1122 <para>The <filename role="special">hgwebdir.cgi</filename>
|
bos@559
|
1123 script relies on an external configuration file. By default,
|
bos@559
|
1124 it searches for a file named <filename
|
bos@559
|
1125 role="special">hgweb.config</filename> in the same directory
|
bos@559
|
1126 as itself. You'll need to create this file, and make it
|
bos@559
|
1127 world-readable. The format of the file is similar to a
|
bos@559
|
1128 Windows <quote>ini</quote> file, as understood by Python's
|
bos@559
|
1129 <literal>ConfigParser</literal>
|
bos@559
|
1130 <citation>web:configparser</citation> module.</para>
|
bos@559
|
1131
|
bos@559
|
1132 <para>The easiest way to configure <filename
|
bos@559
|
1133 role="special">hgwebdir.cgi</filename> is with a section
|
bos@559
|
1134 named <literal>collections</literal>. This will automatically
|
bos@559
|
1135 publish <emphasis>every</emphasis> repository under the
|
bos@559
|
1136 directories you name. The section should look like
|
bos@559
|
1137 this:</para>
|
bos@559
|
1138 <programlisting>[collections] /my/root =
|
bos@559
|
1139 /my/root</programlisting>
|
bos@559
|
1140 <para>Mercurial interprets this by looking at the directory name
|
bos@559
|
1141 on the <emphasis>right</emphasis> hand side of the
|
bos@559
|
1142 <quote><literal>=</literal></quote> sign; finding repositories
|
bos@559
|
1143 in that directory hierarchy; and using the text on the
|
bos@559
|
1144 <emphasis>left</emphasis> to strip off matching text from the
|
bos@559
|
1145 names it will actually list in the web interface. The
|
bos@559
|
1146 remaining component of a path after this stripping has
|
bos@559
|
1147 occurred is called a <quote>virtual path</quote>.</para>
|
bos@559
|
1148
|
bos@559
|
1149 <para>Given the example above, if we have a repository whose
|
bos@559
|
1150 local path is <filename
|
bos@559
|
1151 class="directory">/my/root/this/repo</filename>, the CGI
|
bos@559
|
1152 script will strip the leading <filename
|
bos@559
|
1153 class="directory">/my/root</filename> from the name, and
|
bos@559
|
1154 publish the repository with a virtual path of <filename
|
bos@559
|
1155 class="directory">this/repo</filename>. If the base URL for
|
bos@559
|
1156 our CGI script is <ulink url="http://myhostname/
|
bos@559
|
1157 myuser/hgwebdir.cgi">http://myhostname/
|
bos@559
|
1158 myuser/hgwebdir.cgi</ulink>, the complete URL for that
|
bos@559
|
1159 repository will be <ulink url="http://myhostname/
|
bos@559
|
1160 myuser/hgwebdir.cgi/this/repo">http://myhostname/
|
bos@559
|
1161 myuser/hgwebdir.cgi/this/repo</ulink>.</para>
|
bos@559
|
1162
|
bos@559
|
1163 <para>If we replace <filename
|
bos@559
|
1164 class="directory">/my/root</filename> on the left hand side
|
bos@559
|
1165 of this example with <filename
|
bos@559
|
1166 class="directory">/my</filename>, then <filename
|
bos@559
|
1167 role="special">hgwebdir.cgi</filename> will only strip off
|
bos@559
|
1168 <filename class="directory">/my</filename> from the repository
|
bos@559
|
1169 name, and will give us a virtual path of <filename
|
bos@559
|
1170 class="directory">root/this/repo</filename> instead of
|
bos@559
|
1171 <filename class="directory">this/repo</filename>.</para>
|
bos@559
|
1172
|
bos@559
|
1173 <para>The <filename role="special">hgwebdir.cgi</filename>
|
bos@559
|
1174 script will recursively search each directory listed in the
|
bos@559
|
1175 <literal>collections</literal> section of its configuration
|
bos@559
|
1176 file, but it will <literal>not</literal> recurse into the
|
bos@559
|
1177 repositories it finds.</para>
|
bos@559
|
1178
|
bos@559
|
1179 <para>The <literal>collections</literal> mechanism makes it easy
|
bos@559
|
1180 to publish many repositories in a <quote>fire and
|
bos@559
|
1181 forget</quote> manner. You only need to set up the CGI
|
bos@559
|
1182 script and configuration file one time. Afterwards, you can
|
bos@559
|
1183 publish or unpublish a repository at any time by simply moving
|
bos@559
|
1184 it into, or out of, the directory hierarchy in which you've
|
bos@559
|
1185 configured <filename role="special">hgwebdir.cgi</filename> to
|
bos@559
|
1186 look.</para>
|
bos@559
|
1187
|
bos@559
|
1188 <sect3>
|
bos@559
|
1189 <title>Explicitly specifying which repositories to
|
bos@559
|
1190 publish</title>
|
bos@559
|
1191
|
bos@559
|
1192 <para>In addition to the <literal>collections</literal>
|
bos@559
|
1193 mechanism, the <filename
|
bos@559
|
1194 role="special">hgwebdir.cgi</filename> script allows you
|
bos@559
|
1195 to publish a specific list of repositories. To do so,
|
bos@559
|
1196 create a <literal>paths</literal> section, with contents of
|
bos@559
|
1197 the following form.</para>
|
bos@559
|
1198 <programlisting>[paths] repo1 = /my/path/to/some/repo repo2 =
|
bos@559
|
1199 /some/path/to/another</programlisting>
|
bos@559
|
1200 <para>In this case, the virtual path (the component that will
|
bos@559
|
1201 appear in a URL) is on the left hand side of each
|
bos@559
|
1202 definition, while the path to the repository is on the
|
bos@559
|
1203 right. Notice that there does not need to be any
|
bos@559
|
1204 relationship between the virtual path you choose and the
|
bos@559
|
1205 location of a repository in your filesystem.</para>
|
bos@559
|
1206
|
bos@559
|
1207 <para>If you wish, you can use both the
|
bos@559
|
1208 <literal>collections</literal> and <literal>paths</literal>
|
bos@559
|
1209 mechanisms simultaneously in a single configuration
|
bos@559
|
1210 file.</para>
|
bos@559
|
1211
|
bos@559
|
1212 <note>
|
bos@559
|
1213 <para> If multiple repositories have the same virtual path,
|
bos@559
|
1214 <filename role="special">hgwebdir.cgi</filename> will not
|
bos@559
|
1215 report an error. Instead, it will behave
|
bos@559
|
1216 unpredictably.</para>
|
bos@559
|
1217 </note>
|
bos@559
|
1218
|
bos@559
|
1219 </sect3>
|
bos@559
|
1220 </sect2>
|
bos@559
|
1221 <sect2>
|
bos@559
|
1222 <title>Downloading source archives</title>
|
bos@559
|
1223
|
bos@559
|
1224 <para>Mercurial's web interface lets users download an archive
|
bos@559
|
1225 of any revision. This archive will contain a snapshot of the
|
bos@559
|
1226 working directory as of that revision, but it will not contain
|
bos@559
|
1227 a copy of the repository data.</para>
|
bos@559
|
1228
|
bos@559
|
1229 <para>By default, this feature is not enabled. To enable it,
|
bos@559
|
1230 you'll need to add an <envar
|
bos@559
|
1231 role="rc-item-web">allow_archive</envar> item to the
|
bos@559
|
1232 <literal role="rc-web">web</literal> section of your <filename
|
bos@559
|
1233 role="special"> /.hgrc</filename>.</para>
|
bos@559
|
1234
|
bos@559
|
1235 </sect2>
|
bos@559
|
1236 <sect2>
|
bos@559
|
1237 <title>Web configuration options</title>
|
bos@559
|
1238
|
bos@559
|
1239 <para>Mercurial's web interfaces (the <command role="hg-cmd">hg
|
bos@559
|
1240 serve</command> command, and the <filename
|
bos@559
|
1241 role="special">hgweb.cgi</filename> and <filename
|
bos@559
|
1242 role="special">hgwebdir.cgi</filename> scripts) have a
|
bos@559
|
1243 number of configuration options that you can set. These
|
bos@559
|
1244 belong in a section named <literal
|
bos@559
|
1245 role="rc-web">web</literal>.</para>
|
bos@559
|
1246 <itemizedlist>
|
bos@559
|
1247 <listitem><para><envar
|
bos@559
|
1248 role="rc-item-web">allow_archive</envar>: Determines
|
bos@559
|
1249 which (if any) archive download mechanisms Mercurial
|
bos@559
|
1250 supports. If you enable this feature, users of the web
|
bos@559
|
1251 interface will be able to download an archive of whatever
|
bos@559
|
1252 revision of a repository they are viewing. To enable the
|
bos@559
|
1253 archive feature, this item must take the form of a
|
bos@559
|
1254 sequence of words drawn from the list below.</para>
|
bos@559
|
1255 <itemizedlist>
|
bos@559
|
1256 <listitem><para><literal>bz2</literal>: A
|
bos@559
|
1257 <command>tar</command> archive, compressed using
|
bos@559
|
1258 <literal>bzip2</literal> compression. This has the
|
bos@559
|
1259 best compression ratio, but uses the most CPU time on
|
bos@559
|
1260 the server.</para>
|
bos@559
|
1261 </listitem>
|
bos@559
|
1262 <listitem><para><literal>gz</literal>: A
|
bos@559
|
1263 <command>tar</command> archive, compressed using
|
bos@559
|
1264 <literal>gzip</literal> compression.</para>
|
bos@559
|
1265 </listitem>
|
bos@559
|
1266 <listitem><para><literal>zip</literal>: A
|
bos@559
|
1267 <command>zip</command> archive, compressed using LZW
|
bos@559
|
1268 compression. This format has the worst compression
|
bos@559
|
1269 ratio, but is widely used in the Windows world.</para>
|
bos@559
|
1270 </listitem>
|
bos@559
|
1271 </itemizedlist>
|
bos@559
|
1272 <para> If you provide an empty list, or don't have an
|
bos@559
|
1273 <envar role="rc-item-web">allow_archive</envar> entry at
|
bos@559
|
1274 all, this feature will be disabled. Here is an example of
|
bos@559
|
1275 how to enable all three supported formats.</para>
|
bos@559
|
1276 <programlisting>[web] allow_archive = bz2 gz
|
bos@559
|
1277 zip</programlisting>
|
bos@559
|
1278 </listitem>
|
bos@559
|
1279 <listitem><para><envar role="rc-item-web">allowpull</envar>:
|
bos@559
|
1280 Boolean. Determines whether the web interface allows
|
bos@559
|
1281 remote users to <command role="hg-cmd">hg pull</command>
|
bos@559
|
1282 and <command role="hg-cmd">hg clone</command> this
|
bos@559
|
1283 repository over HTTP. If set to <literal>no</literal> or
|
bos@559
|
1284 <literal>false</literal>, only the
|
bos@559
|
1285 <quote>human-oriented</quote> portion of the web interface
|
bos@559
|
1286 is available.</para>
|
bos@559
|
1287 </listitem>
|
bos@559
|
1288 <listitem><para><envar role="rc-item-web">contact</envar>:
|
bos@559
|
1289 String. A free-form (but preferably brief) string
|
bos@559
|
1290 identifying the person or group in charge of the
|
bos@559
|
1291 repository. This often contains the name and email
|
bos@559
|
1292 address of a person or mailing list. It often makes sense
|
bos@559
|
1293 to place this entry in a repository's own <filename
|
bos@559
|
1294 role="special">.hg/hgrc</filename> file, but it can make
|
bos@559
|
1295 sense to use in a global <filename role="special">
|
bos@559
|
1296 /.hgrc</filename>\ if every repository has a single
|
bos@559
|
1297 maintainer.</para>
|
bos@559
|
1298 </listitem>
|
bos@559
|
1299 <listitem><para><envar role="rc-item-web">maxchanges</envar>:
|
bos@559
|
1300 Integer. The default maximum number of changesets to
|
bos@559
|
1301 display in a single page of output.</para>
|
bos@559
|
1302 </listitem>
|
bos@559
|
1303 <listitem><para><envar role="rc-item-web">maxfiles</envar>:
|
bos@559
|
1304 Integer. The default maximum number of modified files to
|
bos@559
|
1305 display in a single page of output.</para>
|
bos@559
|
1306 </listitem>
|
bos@559
|
1307 <listitem><para><envar role="rc-item-web">stripes</envar>:
|
bos@559
|
1308 Integer. If the web interface displays alternating
|
bos@559
|
1309 <quote>stripes</quote> to make it easier to visually align
|
bos@559
|
1310 rows when you are looking at a table, this number controls
|
bos@559
|
1311 the number of rows in each stripe.</para>
|
bos@559
|
1312 </listitem>
|
bos@559
|
1313 <listitem><para><envar role="rc-item-web">style</envar>:
|
bos@559
|
1314 Controls the template Mercurial uses to display the web
|
bos@559
|
1315 interface. Mercurial ships with two web templates, named
|
bos@559
|
1316 <literal>default</literal> and <literal>gitweb</literal>
|
bos@559
|
1317 (the latter is much more visually attractive). You can
|
bos@559
|
1318 also specify a custom template of your own; see chapter
|
bos@559
|
1319 <xref linkend="chap:template"/> for details.
|
bos@559
|
1320 Here, you can see how to enable the
|
bos@559
|
1321 <literal>gitweb</literal> style.</para>
|
bos@559
|
1322 <programlisting>[web] style = gitweb</programlisting>
|
bos@559
|
1323 </listitem>
|
bos@559
|
1324 <listitem><para><envar role="rc-item-web">templates</envar>:
|
bos@559
|
1325 Path. The directory in which to search for template
|
bos@559
|
1326 files. By default, Mercurial searches in the directory in
|
bos@559
|
1327 which it was installed.</para>
|
bos@559
|
1328 </listitem></itemizedlist>
|
bos@559
|
1329 <para>If you are using <filename
|
bos@559
|
1330 role="special">hgwebdir.cgi</filename>, you can place a few
|
bos@559
|
1331 configuration items in a <literal role="rc-web">web</literal>
|
bos@559
|
1332 section of the <filename
|
bos@559
|
1333 role="special">hgweb.config</filename> file instead of a
|
bos@559
|
1334 <filename role="special"> /.hgrc</filename>\ file, for
|
bos@559
|
1335 convenience. These items are <envar
|
bos@559
|
1336 role="rc-item-web">motd</envar> and <envar
|
bos@559
|
1337 role="rc-item-web">style</envar>.</para>
|
bos@559
|
1338
|
bos@559
|
1339 <sect3>
|
bos@559
|
1340 <title>Options specific to an individual repository</title>
|
bos@559
|
1341
|
bos@559
|
1342 <para>A few <literal role="rc-web">web</literal> configuration
|
bos@559
|
1343 items ought to be placed in a repository's local <filename
|
bos@559
|
1344 role="special">.hg/hgrc</filename>, rather than a user's
|
bos@559
|
1345 or global <filename role="special">
|
bos@559
|
1346 /.hgrc</filename>.</para>
|
bos@559
|
1347 <itemizedlist>
|
bos@559
|
1348 <listitem><para><envar
|
bos@559
|
1349 role="rc-item-web">description</envar>: String. A
|
bos@559
|
1350 free-form (but preferably brief) string that describes
|
bos@559
|
1351 the contents or purpose of the repository.</para>
|
bos@559
|
1352 </listitem>
|
bos@559
|
1353 <listitem><para><envar role="rc-item-web">name</envar>:
|
bos@559
|
1354 String. The name to use for the repository in the web
|
bos@559
|
1355 interface. This overrides the default name, which is
|
bos@559
|
1356 the last component of the repository's path.</para>
|
bos@559
|
1357 </listitem></itemizedlist>
|
bos@559
|
1358
|
bos@559
|
1359 </sect3>
|
bos@559
|
1360 <sect3>
|
bos@559
|
1361 <title>Options specific to the <command role="hg-cmd">hg
|
bos@559
|
1362 serve</command> command</title>
|
bos@559
|
1363
|
bos@559
|
1364 <para>Some of the items in the <literal
|
bos@559
|
1365 role="rc-web">web</literal> section of a <filename
|
bos@559
|
1366 role="special"> /.hgrc</filename>\ file are only for use
|
bos@559
|
1367 with the <command role="hg-cmd">hg serve</command>
|
bos@559
|
1368 command.</para>
|
bos@559
|
1369 <itemizedlist>
|
bos@559
|
1370 <listitem><para><envar role="rc-item-web">accesslog</envar>:
|
bos@559
|
1371 Path. The name of a file into which to write an access
|
bos@559
|
1372 log. By default, the <command role="hg-cmd">hg
|
bos@559
|
1373 serve</command> command writes this information to
|
bos@559
|
1374 standard output, not to a file. Log entries are written
|
bos@559
|
1375 in the standard <quote>combined</quote> file format used
|
bos@559
|
1376 by almost all web servers.</para>
|
bos@559
|
1377 </listitem>
|
bos@559
|
1378 <listitem><para><envar role="rc-item-web">address</envar>:
|
bos@559
|
1379 String. The local address on which the server should
|
bos@559
|
1380 listen for incoming connections. By default, the server
|
bos@559
|
1381 listens on all addresses.</para>
|
bos@559
|
1382 </listitem>
|
bos@559
|
1383 <listitem><para><envar role="rc-item-web">errorlog</envar>:
|
bos@559
|
1384 Path. The name of a file into which to write an error
|
bos@559
|
1385 log. By default, the <command role="hg-cmd">hg
|
bos@559
|
1386 serve</command> command writes this information to
|
bos@559
|
1387 standard error, not to a file.</para>
|
bos@559
|
1388 </listitem>
|
bos@559
|
1389 <listitem><para><envar role="rc-item-web">ipv6</envar>:
|
bos@559
|
1390 Boolean. Whether to use the IPv6 protocol. By default,
|
bos@559
|
1391 IPv6 is not used.</para>
|
bos@559
|
1392 </listitem>
|
bos@559
|
1393 <listitem><para><envar role="rc-item-web">port</envar>:
|
bos@559
|
1394 Integer. The TCP port number on which the server should
|
bos@559
|
1395 listen. The default port number used is 8000.</para>
|
bos@559
|
1396 </listitem></itemizedlist>
|
bos@559
|
1397
|
bos@559
|
1398 </sect3>
|
bos@559
|
1399 <sect3>
|
bos@559
|
1400 <title>Choosing the right <filename role="special">
|
bos@559
|
1401 /.hgrc</filename>\ file to add <literal
|
bos@559
|
1402 role="rc-web">web</literal> items to</title>
|
bos@559
|
1403
|
bos@559
|
1404 <para>It is important to remember that a web server like
|
bos@559
|
1405 Apache or <literal>lighttpd</literal> will run under a user
|
bos@559
|
1406 ID that is different to yours. CGI scripts run by your
|
bos@559
|
1407 server, such as <filename
|
bos@559
|
1408 role="special">hgweb.cgi</filename>, will usually also run
|
bos@559
|
1409 under that user ID.</para>
|
bos@559
|
1410
|
bos@559
|
1411 <para>If you add <literal role="rc-web">web</literal> items to
|
bos@559
|
1412 your own personal <filename role="special">
|
bos@559
|
1413 /.hgrc</filename>\ file, CGI scripts won't read that
|
bos@559
|
1414 <filename role="special"> /.hgrc</filename>\ file. Those
|
bos@559
|
1415 settings will thus only affect the behaviour of the <command
|
bos@559
|
1416 role="hg-cmd">hg serve</command> command when you run it.
|
bos@559
|
1417 To cause CGI scripts to see your settings, either create a
|
bos@559
|
1418 <filename role="special"> /.hgrc</filename>\ file in the
|
bos@559
|
1419 home directory of the user ID that runs your web server, or
|
bos@559
|
1420 add those settings to a system-wide <filename
|
bos@559
|
1421 role="special"> /.hgrc</filename>\ file.</para>
|
bos@559
|
1422
|
bos@559
|
1423
|
bos@559
|
1424 </sect3>
|
bos@559
|
1425 </sect2>
|
bos@559
|
1426 </sect1>
|
bos@559
|
1427 </chapter>
|
bos@559
|
1428
|
bos@559
|
1429 <!--
|
bos@559
|
1430 local variables:
|
bos@559
|
1431 sgml-parent-document: ("00book.xml" "book" "chapter")
|
bos@559
|
1432 end:
|
bos@559
|
1433 -->
|