Documentation/git-http-backend.txt

   1 git-http-backend(1)
   2 ===================
   3
   4 NAME
   5 ----
   6 git-http-backend - Server side implementation of Git over HTTP
   7
   8 SYNOPSIS
   9 --------
  10 [verse]
  11 'git http-backend'
  12
  13 DESCRIPTION
  14 -----------
  15 A simple CGI program to serve the contents of a Git repository to Git
  16 clients accessing the repository over http:// and https:// protocols.
  17 The program supports clients fetching using both the smart HTTP protocol
  18 and the backwards-compatible dumb HTTP protocol, as well as clients
  19 pushing using the smart HTTP protocol.
  20
  21 It verifies that the directory has the magic file
  22 "git-daemon-export-ok", and it will refuse to export any Git directory
  23 that hasn't explicitly been marked for export this way (unless the
  24 `GIT_HTTP_EXPORT_ALL` environmental variable is set).
  25
  26 By default, only the `upload-pack` service is enabled, which serves
  27 'git fetch-pack' and 'git ls-remote' clients, which are invoked from
  28 'git fetch', 'git pull', and 'git clone'.  If the client is authenticated,
  29 the `receive-pack` service is enabled, which serves 'git send-pack'
  30 clients, which is invoked from 'git push'.
  31
  32 SERVICES
  33 --------
  34 These services can be enabled/disabled using the per-repository
  35 configuration file:
  36
  37 http.getanyfile::
  38         This serves Git clients older than version 1.6.6 that are unable to use the
  39         upload pack service.  When enabled, clients are able to read
  40         any file within the repository, including objects that are
  41         no longer reachable from a branch but are still present.
  42         It is enabled by default, but a repository can disable it
  43         by setting this configuration item to `false`.
  44
  45 http.uploadpack::
  46         This serves 'git fetch-pack' and 'git ls-remote' clients.
  47         It is enabled by default, but a repository can disable it
  48         by setting this configuration item to `false`.
  49
  50 http.receivepack::
  51         This serves 'git send-pack' clients, allowing push.  It is
  52         disabled by default for anonymous users, and enabled by
  53         default for users authenticated by the web server.  It can be
  54         disabled by setting this item to `false`, or enabled for all
  55         users, including anonymous users, by setting it to `true`.
  56
  57 URL TRANSLATION
  58 ---------------
  59 To determine the location of the repository on disk, 'git http-backend'
  60 concatenates the environment variables PATH_INFO, which is set
  61 automatically by the web server, and GIT_PROJECT_ROOT, which must be set
  62 manually in the web server configuration.  If GIT_PROJECT_ROOT is not
  63 set, 'git http-backend' reads PATH_TRANSLATED, which is also set
  64 automatically by the web server.
  65
  66 EXAMPLES
  67 --------
  68 All of the following examples map `http://$hostname/git/foo/bar.git`
  69 to `/var/www/git/foo/bar.git`.
  70
  71 Apache 2.x::
  72         Ensure mod_cgi, mod_alias, and mod_env are enabled, set
  73         GIT_PROJECT_ROOT (or DocumentRoot) appropriately, and
  74         create a ScriptAlias to the CGI:
  75 +
  76 ----------------------------------------------------------------
  77 SetEnv GIT_PROJECT_ROOT /var/www/git
  78 SetEnv GIT_HTTP_EXPORT_ALL
  79 ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/
  80 ----------------------------------------------------------------
  81 +
  82 To enable anonymous read access but authenticated write access,
  83 require authorization for both the initial ref advertisement (which we
  84 detect as a push via the service parameter in the query string), and the
  85 receive-pack invocation itself:
  86 +
  87 ----------------------------------------------------------------
  88 RewriteCond %{QUERY_STRING} service=git-receive-pack [OR]
  89 RewriteCond %{REQUEST_URI} /git-receive-pack$
  90 RewriteRule ^/git/ - [E=AUTHREQUIRED:yes]
  91
  92 <LocationMatch "^/git/">
  93         Order Deny,Allow
  94         Deny from env=AUTHREQUIRED
  95
  96         AuthType Basic
  97         AuthName "Git Access"
  98         Require group committers
  99         Satisfy Any
 100         ...
 101 </LocationMatch>
 102 ----------------------------------------------------------------
 103 +
 104 If you do not have `mod_rewrite` available to match against the query
 105 string, it is sufficient to just protect `git-receive-pack` itself,
 106 like:
 107 +
 108 ----------------------------------------------------------------
 109 <LocationMatch "^/git/.*/git-receive-pack$">
 110         AuthType Basic
 111         AuthName "Git Access"
 112         Require group committers
 113         ...
 114 </LocationMatch>
 115 ----------------------------------------------------------------
 116 +
 117 In this mode, the server will not request authentication until the
 118 client actually starts the object negotiation phase of the push, rather
 119 than during the initial contact.  For this reason, you must also enable
 120 the `http.receivepack` config option in any repositories that should
 121 accept a push. The default behavior, if `http.receivepack` is not set,
 122 is to reject any pushes by unauthenticated users; the initial request
 123 will therefore report `403 Forbidden` to the client, without even giving
 124 an opportunity for authentication.
 125 +
 126 To require authentication for both reads and writes, use a Location
 127 directive around the repository, or one of its parent directories:
 128 +
 129 ----------------------------------------------------------------
 130 <Location /git/private>
 131         AuthType Basic
 132         AuthName "Private Git Access"
 133         Require group committers
 134         ...
 135 </Location>
 136 ----------------------------------------------------------------
 137 +
 138 To serve gitweb at the same url, use a ScriptAliasMatch to only
 139 those URLs that 'git http-backend' can handle, and forward the
 140 rest to gitweb:
 141 +
 142 ----------------------------------------------------------------
 143 ScriptAliasMatch \
 144         "(?x)^/git/(.*/(HEAD | \
 145                         info/refs | \
 146                         objects/(info/[^/]+ | \
 147                                  [0-9a-f]{2}/[0-9a-f]{38} | \
 148                                  pack/pack-[0-9a-f]{40}\.(pack|idx)) | \
 149                         git-(upload|receive)-pack))$" \
 150         /usr/libexec/git-core/git-http-backend/$1
 151
 152 ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/
 153 ----------------------------------------------------------------
 154 +
 155 To serve multiple repositories from different linkgit:gitnamespaces[7] in a
 156 single repository:
 157 +
 158 ----------------------------------------------------------------
 159 SetEnvIf Request_URI "^/git/([^/]*)" GIT_NAMESPACE=$1
 160 ScriptAliasMatch ^/git/[^/]*(.*) /usr/libexec/git-core/git-http-backend/storage.git$1
 161 ----------------------------------------------------------------
 162
 163 Accelerated static Apache 2.x::
 164         Similar to the above, but Apache can be used to return static
 165         files that are stored on disk.  On many systems this may
 166         be more efficient as Apache can ask the kernel to copy the
 167         file contents from the file system directly to the network:
 168 +
 169 ----------------------------------------------------------------
 170 SetEnv GIT_PROJECT_ROOT /var/www/git
 171
 172 AliasMatch ^/git/(.*/objects/[0-9a-f]{2}/[0-9a-f]{38})$          /var/www/git/$1
 173 AliasMatch ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.(pack|idx))$ /var/www/git/$1
 174 ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/
 175 ----------------------------------------------------------------
 176 +
 177 This can be combined with the gitweb configuration:
 178 +
 179 ----------------------------------------------------------------
 180 SetEnv GIT_PROJECT_ROOT /var/www/git
 181
 182 AliasMatch ^/git/(.*/objects/[0-9a-f]{2}/[0-9a-f]{38})$          /var/www/git/$1
 183 AliasMatch ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.(pack|idx))$ /var/www/git/$1
 184 ScriptAliasMatch \
 185         "(?x)^/git/(.*/(HEAD | \
 186                         info/refs | \
 187                         objects/info/[^/]+ | \
 188                         git-(upload|receive)-pack))$" \
 189         /usr/libexec/git-core/git-http-backend/$1
 190 ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/
 191 ----------------------------------------------------------------
 192
 193 Lighttpd::
 194         Ensure that `mod_cgi`, `mod_alias`, `mod_auth`, `mod_setenv` are
 195         loaded, then set `GIT_PROJECT_ROOT` appropriately and redirect
 196         all requests to the CGI:
 197 +
 198 ----------------------------------------------------------------
 199 alias.url += ( "/git" => "/usr/lib/git-core/git-http-backend" )
 200 $HTTP["url"] =~ "^/git" {
 201         cgi.assign = ("" => "")
 202         setenv.add-environment = (
 203                 "GIT_PROJECT_ROOT" => "/var/www/git",
 204                 "GIT_HTTP_EXPORT_ALL" => ""
 205         )
 206 }
 207 ----------------------------------------------------------------
 208 +
 209 To enable anonymous read access but authenticated write access:
 210 +
 211 ----------------------------------------------------------------
 212 $HTTP["querystring"] =~ "service=git-receive-pack" {
 213         include "git-auth.conf"
 214 }
 215 $HTTP["url"] =~ "^/git/.*/git-receive-pack$" {
 216         include "git-auth.conf"
 217 }
 218 ----------------------------------------------------------------
 219 +
 220 where `git-auth.conf` looks something like:
 221 +
 222 ----------------------------------------------------------------
 223 auth.require = (
 224         "/" => (
 225                 "method" => "basic",
 226                 "realm" => "Git Access",
 227                 "require" => "valid-user"
 228                )
 229 )
 230 # ...and set up auth.backend here
 231 ----------------------------------------------------------------
 232 +
 233 To require authentication for both reads and writes:
 234 +
 235 ----------------------------------------------------------------
 236 $HTTP["url"] =~ "^/git/private" {
 237         include "git-auth.conf"
 238 }
 239 ----------------------------------------------------------------
 240
 241
 242 ENVIRONMENT
 243 -----------
 244 'git http-backend' relies upon the `CGI` environment variables set
 245 by the invoking web server, including:
 246
 247 * PATH_INFO (if GIT_PROJECT_ROOT is set, otherwise PATH_TRANSLATED)
 248 * REMOTE_USER
 249 * REMOTE_ADDR
 250 * CONTENT_TYPE
 251 * QUERY_STRING
 252 * REQUEST_METHOD
 253
 254 The `GIT_HTTP_EXPORT_ALL` environmental variable may be passed to
 255 'git-http-backend' to bypass the check for the "git-daemon-export-ok"
 256 file in each repository before allowing export of that repository.
 257
 258 The `GIT_HTTP_MAX_REQUEST_BUFFER` environment variable (or the
 259 `http.maxRequestBuffer` config variable) may be set to change the
 260 largest ref negotiation request that git will handle during a fetch; any
 261 fetch requiring a larger buffer will not succeed.  This value should not
 262 normally need to be changed, but may be helpful if you are fetching from
 263 a repository with an extremely large number of refs.  The value can be
 264 specified with a unit (e.g., `100M` for 100 megabytes). The default is
 265 10 megabytes.
 266
 267 The backend process sets GIT_COMMITTER_NAME to '$REMOTE_USER' and
 268 GIT_COMMITTER_EMAIL to '$\{REMOTE_USER}@http.$\{REMOTE_ADDR\}',
 269 ensuring that any reflogs created by 'git-receive-pack' contain some
 270 identifying information of the remote user who performed the push.
 271
 272 All `CGI` environment variables are available to each of the hooks
 273 invoked by the 'git-receive-pack'.
 274
 275 GIT
 276 ---
 277 Part of the linkgit:git[1] suite