diskimage-builder/elements/source-repositories/README.md
Chris Jones 4c7a3bf79f Improve source-repositories git caching.
We now unconditionally cache the repositories being fetched with
source-repositories.

Additionally, by improving the way we handle repository refs, we are now
able to build images with code taken directly from gerrit reviews.

Change-Id: Ifd4c5691f6761eb5551663e6d0aa1c0e42afced3
2013-12-20 14:48:30 +00:00

2.3 KiB

With this element other elements can register source code repositories by placing their details in the file source-repository-*. An example of an element "custom-element" that wants to retrieve the ironic source from git and pbr from a tarball would be

File : elements/custom-element/source-repository-ironic

#<name> <type> <destination> <location> [<ref>]
# <ref> defaults to master if not specified
ironic git /usr/local/ironic git://git.openstack.org/openstack/ironic.git

File : elements/custom-element/source-repository-pbr

pbr tar /usr/local/pbr http://tarballs.openstack.org/pbr/pbr-master.tar.gz

diskimage-builder will then retrieve the sources specified and place them at the directory <destination>

A number of environment variables can be set by the process calling diskimage-builder which can change the details registered by the element, these are

DIB_REPOTYPE_<name>     : change the registered type
DIB_REPOLOCATION_<name> : change the registered location
DIB_REPOREF_<name>      : change the registered reference

for example if you would like diskimage-builder to get ironic from a local mirror you could set DIB_REPOLOCATION_ironic=git://localgitserver/ironic.git

Alternatively if you would like to use the keystone element and build an image with keystone from a stable branch then you would set DIB_REPOREF_keystone=stable/grizzly

If you wish to build an image using code from a gerrit review, you can set DIB_REPOLOCATION_ and DIB_REPOREF_ to the values given by gerrit in the fetch/pull section of a review. For example:

DIB_REPOLOCATION_nova=https://review.openstack.org/openstack/nova
DIB_REPOREF_nova=refs/changes/72/61972/8

Git sources will be cloned to <destination>

Tarballs will be extracted to <destination>. Tarballs should contain a single topleval directory, regardless of the name of this top level directory it will be renamed to <destination>

If multiple elements register a source location with the same then source-repositories will exit with an error. Care should therefore be taken to only use elements together that download source to different locations.

The repository paths built into the image are stored in etc/dib-source-repositories, one repository per line. This permits later review of the repositories (by users or by other elements).