Documentation/technical/bundle-format.txt

   1 = Git bundle v2 format
   2
   3 The Git bundle format is a format that represents both refs and Git objects.
   4
   5 == Format
   6
   7 We will use ABNF notation to define the Git bundle format. See
   8 protocol-common.txt for the details.
   9
  10 ----
  11 bundle    = signature *prerequisite *reference LF pack
  12 signature = "# v2 git bundle" LF
  13
  14 prerequisite = "-" obj-id SP comment LF
  15 comment      = *CHAR
  16 reference    = obj-id SP refname LF
  17
  18 pack         = ... ; packfile
  19 ----
  20
  21 == Semantics
  22
  23 A Git bundle consists of three parts.
  24
  25 * "Prerequisites" lists the objects that are NOT included in the bundle and the
  26   reader of the bundle MUST already have, in order to use the data in the
  27   bundle. The objects stored in the bundle may refer to prerequisite objects and
  28   anything reachable from them (e.g. a tree object in the bundle can reference
  29   a blob that is reachable from a prerequisite) and/or expressed as a delta
  30   against prerequisite objects.
  31
  32 * "References" record the tips of the history graph, iow, what the reader of the
  33   bundle CAN "git fetch" from it.
  34
  35 * "Pack" is the pack data stream "git fetch" would send, if you fetch from a
  36   repository that has the references recorded in the "References" above into a
  37   repository that has references pointing at the objects listed in
  38   "Prerequisites" above.
  39
  40 In the bundle format, there can be a comment following a prerequisite obj-id.
  41 This is a comment and it has no specific meaning. The writer of the bundle MAY
  42 put any string here. The reader of the bundle MUST ignore the comment.
  43
  44 === Note on the shallow clone and a Git bundle
  45
  46 Note that the prerequisites does not represent a shallow-clone boundary. The
  47 semantics of the prerequisites and the shallow-clone boundaries are different,
  48 and the Git bundle v2 format cannot represent a shallow clone repository.