1
 2                       cgit - cgi for git
 3
 4
 5This is an attempt to create a fast web interface for the git scm, using a 
 6frontside cache to decrease server io-pressure.
 7
 8When cgit is invoked, it looks for a cached page matching the request. If no
 9such cachefile exist (or it has expired), it is (re)generated. Finally, the
10cachefile is returned to the client.
11
12If the cachefile has expired, but cgit is unable to lock the cachefile, the 
13client will get the stale cachefile after all. This is done to favour page
14throughput over page freshness.
15
16Also, when a cachefile is generated, a few cache-related http-headers are
17created: "Modified" is set to current time(2), while "Expires" is set to 
18time(2) + <cachefile TTL> * 60 (unless the TTL is negative, in which case it
19is read as "60 * 60 * 24 * 365"). This is done to avoid repeated requests for
20already visited pages.
21
22The following cache-related options can be set in /etc/cgitrc:
23
24  cache-root=<path>           root directory for cache files
25  cache-root-ttl=<min>        TTL for the repo listing page
26  cache-repo-ttl=<min>        TTL for repo summary pages
27  cache-dynamic-ttl=<min>     TTL for pages with symbolic references
28  cache-static-ttl=<min>      TTL for pages with sha1 references
29
30The cachefiles are split into different directories, based on the requested
31repository and page:
32
33  Repo listing:  <cachedir>/index.html
34  Repo summary:  <cachedir>/<repo>/index.html
35  Repo subpage:  <cachedir>/<repo>/<page>/<querystring>.html