Re: [PATCH] doc: describe Git bundle format

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi,

On Thu, 30 Jan 2020, Masaya Suzuki wrote:

> The bundle format was not documented. Describe the format with ABNF and
> explain the meaning of each part.

LGTM,
Dscho

>
> Signed-off-by: Masaya Suzuki <masayasuzuki@google.com>
> ---
>  Documentation/technical/bundle-format.txt | 40 +++++++++++++++++++++++
>  1 file changed, 40 insertions(+)
>  create mode 100644 Documentation/technical/bundle-format.txt
>
> diff --git a/Documentation/technical/bundle-format.txt b/Documentation/technical/bundle-format.txt
> new file mode 100644
> index 0000000000..dbb80225b5
> --- /dev/null
> +++ b/Documentation/technical/bundle-format.txt
> @@ -0,0 +1,40 @@
> += Git bundle v2 format
> +
> +The Git bundle format is a format that represents both refs and Git objects.
> +
> +== Format
> +
> +We will use ABNF notation to define the Git bundle format. See
> +protocol-common.txt for the details.
> +
> +----
> +bundle    = signature references pack
> +signature = "# v2 git bundle" LF
> +
> +references   = *(prerequisite / ref) LF
> +prerequisite = "-" obj-id SP comment LF
> +comment      = *CHAR
> +ref          = obj-id SP refname LF
> +
> +pack         = ... ; packfile
> +----
> +
> +== Semantics
> +
> +A Git bundle consists of three parts.
> +
> +*   Prerequisites: Optional list of objects that are not included in the bundle
> +    file. A bundle can reference these prerequisite objects (or it can reference
> +    the objects reachable from the prerequisite objects). The bundle itself
> +    might not contain those objects.
> +*   References: Mapping of ref names to objects.
> +*   Git objects: Commit, tree, blob, and tags. These are included in the pack
> +    format.
> +
> +If a bundle contains prerequisites, it means the bundle has a thin pack and the
> +bundle alone is not enough for resolving all objects. When you read such
> +bundles, you should have those missing objects beforehand.
> +
> +In the bundle format, there can be a comment following a prerequisite obj-id.
> +This is a comment and it has no specific meaning. When you write a bundle, you
> +can put any string here. When you read a bundle, you can ignore this part.
> --
> 2.25.0.341.g760bfbb309-goog
>
>