Documentation / git-http-backend.txton commit refs/files-backend: don't look at an aborted transaction (d3322eb)
   1git-http-backend(1)
   2===================
   3
   4NAME
   5----
   6git-http-backend - Server side implementation of Git over HTTP
   7
   8SYNOPSIS
   9--------
  10[verse]
  11'git http-backend'
  12
  13DESCRIPTION
  14-----------
  15A simple CGI program to serve the contents of a Git repository to Git
  16clients accessing the repository over http:// and https:// protocols.
  17The program supports clients fetching using both the smart HTTP protocol
  18and the backwards-compatible dumb HTTP protocol, as well as clients
  19pushing using the smart HTTP protocol.
  20
  21It verifies that the directory has the magic file
  22"git-daemon-export-ok", and it will refuse to export any Git directory
  23that hasn't explicitly been marked for export this way (unless the
  24`GIT_HTTP_EXPORT_ALL` environmental variable is set).
  25
  26By 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,
  29the `receive-pack` service is enabled, which serves 'git send-pack'
  30clients, which is invoked from 'git push'.
  31
  32SERVICES
  33--------
  34These services can be enabled/disabled using the per-repository
  35configuration file:
  36
  37http.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
  45http.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
  50http.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
  57URL TRANSLATION
  58---------------
  59To determine the location of the repository on disk, 'git http-backend'
  60concatenates the environment variables PATH_INFO, which is set
  61automatically by the web server, and GIT_PROJECT_ROOT, which must be set
  62manually in the web server configuration.  If GIT_PROJECT_ROOT is not
  63set, 'git http-backend' reads PATH_TRANSLATED, which is also set
  64automatically by the web server.
  65
  66EXAMPLES
  67--------
  68All of the following examples map `http://$hostname/git/foo/bar.git`
  69to `/var/www/git/foo/bar.git`.
  70
  71Apache 2.x::
  72        Ensure mod_cgi, mod_alias, and mod_env are enabled, set
  73        GIT_PROJECT_ROOT (or DocumentRoot) appropriately, and
  74        create a ScriptAlias to the CGI:
  75+
  76----------------------------------------------------------------
  77SetEnv GIT_PROJECT_ROOT /var/www/git
  78SetEnv GIT_HTTP_EXPORT_ALL
  79ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/
  80----------------------------------------------------------------
  81+
  82To enable anonymous read access but authenticated write access,
  83require authorization for both the initial ref advertisement (which we
  84detect as a push via the service parameter in the query string), and the
  85receive-pack invocation itself:
  86+
  87----------------------------------------------------------------
  88RewriteCond %{QUERY_STRING} service=git-receive-pack [OR]
  89RewriteCond %{REQUEST_URI} /git-receive-pack$
  90RewriteRule ^/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+
 104If you do not have `mod_rewrite` available to match against the query
 105string, it is sufficient to just protect `git-receive-pack` itself,
 106like:
 107+
 108----------------------------------------------------------------
 109<LocationMatch "^/git/.*/git-receive-pack$">
 110        AuthType Basic
 111        AuthName "Git Access"
 112        Require group committers
 113        ...
 114</LocationMatch>
 115----------------------------------------------------------------
 116+
 117In this mode, the server will not request authentication until the
 118client actually starts the object negotiation phase of the push, rather
 119than during the initial contact.  For this reason, you must also enable
 120the `http.receivepack` config option in any repositories that should
 121accept a push. The default behavior, if `http.receivepack` is not set,
 122is to reject any pushes by unauthenticated users; the initial request
 123will therefore report `403 Forbidden` to the client, without even giving
 124an opportunity for authentication.
 125+
 126To require authentication for both reads and writes, use a Location
 127directive around the repository, or one of its parent directories:
 128+
 129----------------------------------------------------------------
 130<Location /git/private>
 131        AuthType Basic
 132        AuthName "Private Git Access"
 133        Require group committers
 134        ...
 135</Location>
 136----------------------------------------------------------------
 137+
 138To serve gitweb at the same url, use a ScriptAliasMatch to only
 139those URLs that 'git http-backend' can handle, and forward the
 140rest to gitweb:
 141+
 142----------------------------------------------------------------
 143ScriptAliasMatch \
 144        "(?x)^/git/(.*/(HEAD | \
 145                        info/refs | \
 146                        objects/(info/[^/]+ | \
 147                                 [0-9a-f]{2}/[0-9a-f]{38} | \
 148                                 pack/pack-[0-9a-f]{40}\.(pack|idx)) | \
 149                        git-(upload|receive)-pack))$" \
 150        /usr/libexec/git-core/git-http-backend/$1
 151
 152ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/
 153----------------------------------------------------------------
 154+
 155To serve multiple repositories from different linkgit:gitnamespaces[7] in a
 156single repository:
 157+
 158----------------------------------------------------------------
 159SetEnvIf Request_URI "^/git/([^/]*)" GIT_NAMESPACE=$1
 160ScriptAliasMatch ^/git/[^/]*(.*) /usr/libexec/git-core/git-http-backend/storage.git$1
 161----------------------------------------------------------------
 162
 163Accelerated static Apache 2.x::
 164        Similar to the above, but Apache can be used to return static
 165        files that are stored on disk.  On many systems this may
 166        be more efficient as Apache can ask the kernel to copy the
 167        file contents from the file system directly to the network:
 168+
 169----------------------------------------------------------------
 170SetEnv GIT_PROJECT_ROOT /var/www/git
 171
 172AliasMatch ^/git/(.*/objects/[0-9a-f]{2}/[0-9a-f]{38})$          /var/www/git/$1
 173AliasMatch ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.(pack|idx))$ /var/www/git/$1
 174ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/
 175----------------------------------------------------------------
 176+
 177This can be combined with the gitweb configuration:
 178+
 179----------------------------------------------------------------
 180SetEnv GIT_PROJECT_ROOT /var/www/git
 181
 182AliasMatch ^/git/(.*/objects/[0-9a-f]{2}/[0-9a-f]{38})$          /var/www/git/$1
 183AliasMatch ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.(pack|idx))$ /var/www/git/$1
 184ScriptAliasMatch \
 185        "(?x)^/git/(.*/(HEAD | \
 186                        info/refs | \
 187                        objects/info/[^/]+ | \
 188                        git-(upload|receive)-pack))$" \
 189        /usr/libexec/git-core/git-http-backend/$1
 190ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/
 191----------------------------------------------------------------
 192
 193Lighttpd::
 194        Ensure that `mod_cgi`, `mod_alias`, `mod_auth`, `mod_setenv` are
 195        loaded, then set `GIT_PROJECT_ROOT` appropriately and redirect
 196        all requests to the CGI:
 197+
 198----------------------------------------------------------------
 199alias.url += ( "/git" => "/usr/lib/git-core/git-http-backend" )
 200$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+
 209To 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$" {
 216        include "git-auth.conf"
 217}
 218----------------------------------------------------------------
 219+
 220where `git-auth.conf` looks something like:
 221+
 222----------------------------------------------------------------
 223auth.require = (
 224        "/" => (
 225                "method" => "basic",
 226                "realm" => "Git Access",
 227                "require" => "valid-user"
 228               )
 229)
 230# ...and set up auth.backend here
 231----------------------------------------------------------------
 232+
 233To require authentication for both reads and writes:
 234+
 235----------------------------------------------------------------
 236$HTTP["url"] =~ "^/git/private" {
 237        include "git-auth.conf"
 238}
 239----------------------------------------------------------------
 240
 241
 242ENVIRONMENT
 243-----------
 244'git http-backend' relies upon the `CGI` environment variables set
 245by 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
 254The `GIT_HTTP_EXPORT_ALL` environmental variable may be passed to
 255'git-http-backend' to bypass the check for the "git-daemon-export-ok"
 256file in each repository before allowing export of that repository.
 257
 258The `GIT_HTTP_MAX_REQUEST_BUFFER` environment variable (or the
 259`http.maxRequestBuffer` config variable) may be set to change the
 260largest ref negotiation request that git will handle during a fetch; any
 261fetch requiring a larger buffer will not succeed.  This value should not
 262normally need to be changed, but may be helpful if you are fetching from
 263a repository with an extremely large number of refs.  The value can be
 264specified with a unit (e.g., `100M` for 100 megabytes). The default is
 26510 megabytes.
 266
 267The backend process sets GIT_COMMITTER_NAME to '$REMOTE_USER' and
 268GIT_COMMITTER_EMAIL to '$\{REMOTE_USER}@http.$\{REMOTE_ADDR\}',
 269ensuring that any reflogs created by 'git-receive-pack' contain some
 270identifying information of the remote user who performed the push.
 271
 272All `CGI` environment variables are available to each of the hooks
 273invoked by the 'git-receive-pack'.
 274
 275GIT
 276---
 277Part of the linkgit:git[1] suite