GITFORMAT-BUNDLE(5) Git Manual GITFORMAT-BUNDLE(5)
NAME
gitformat-bundle - The bundle file format
SYNOPSIS
*.bundle
*.bdl
DESCRIPTION
The Git bundle format is a format that represents both refs and Git
objects. A bundle is a header in a format similar to git-show-ref(1)
followed by a pack in *.pack format.
The format is created and read by the git-bundle(1) command, and
supported by e.g. git-fetch(1) and git-clone(1).
FORMAT
We will use ABNF notation to define the Git bundle format. See
gitprotocol-common(5) for the details.
A v2 bundle looks like this:
bundle = signature *prerequisite *reference LF pack
signature = "# v2 git bundle" LF
prerequisite = "-" obj-id SP comment LF
comment = *CHAR
reference = obj-id SP refname LF
pack = ... ; packfile
A v3 bundle looks like this:
bundle = signature *capability *prerequisite *reference LF pack
signature = "# v3 git bundle" LF
capability = "@" key ["=" value] LF
prerequisite = "-" obj-id SP comment LF
comment = *CHAR
reference = obj-id SP refname LF
key = 1*(ALPHA / DIGIT / "-")
value = *(%01-09 / %0b-FF)
pack = ... ; packfile
SEMANTICS
A Git bundle consists of several parts.
• "Capabilities", which are only in the v3 format, indicate
functionality that the bundle requires to be read properly.
• "Prerequisites" lists the objects that are NOT included in the
bundle and the reader of the bundle MUST already have, in order to
use the data in the bundle. The objects stored in the bundle may
refer to prerequisite objects and anything reachable from them
(e.g. a tree object in the bundle can reference a blob that is
reachable from a prerequisite) and/or expressed as a delta against
prerequisite objects.
• "References" record the tips of the history graph, iow, what the
reader of the bundle CAN "git fetch" from it.
• "Pack" is the pack data stream "git fetch" would send, if you fetch
from a repository that has the references recorded in the
"References" above into a repository that has references pointing
at the objects listed in "Prerequisites" above.
In the bundle format, there can be a comment following a prerequisite
obj-id. This is a comment and it has no specific meaning. The writer of
the bundle MAY put any string here. The reader of the bundle MUST
ignore the comment.
Note on the shallow clone and a Git bundle
Note that the prerequisites does not represent a shallow-clone
boundary. The semantics of the prerequisites and the shallow-clone
boundaries are different, and the Git bundle v2 format cannot represent
a shallow clone repository.
CAPABILITIES
Because there is no opportunity for negotiation, unknown capabilities
cause git bundle to abort.
• object-format specifies the hash algorithm in use, and can take the
same values as the extensions.objectFormat configuration value.
• filter specifies an object filter as in the --filter option in git-
rev-list(1). The resulting pack-file must be marked as a .promisor
pack-file after it is unbundled.
GIT
Part of the git(1) suite
Git 2.39.2 02/28/2023 GITFORMAT-BUNDLE(5)
Generated by dwww version 1.15 on Fri Jun 21 07:29:37 CEST 2024.