Prettyfy source-repositories doc

Largely enhance the documentation so it renders nicely when generated
with Sphinx.

Culpirt: the 'package' type is documented but unhandled in the shell
script.

Change-Id: I9f4f46e770077c147c0a5b1245b779bc3afa4e98
This commit is contained in:
Antoine Musso 2015-09-17 13:24:46 +02:00
parent bcce4842cf
commit 71950d8bcd

View file

@ -2,89 +2,69 @@
source-repositories
===================
With this element other elements can register their installation source 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
placing their details in the file ``source-repository-*``.
*File : elements/custom-element/source-repository-ironic*
source-repository-* file format
-------------------------------
#<name> <type> <destination> <location> [<ref>]
# <ref> defaults to master if not specified.
# A value of "*" prunes and fetches all heads and tags.
ironic git /usr/local/ironic git://git.openstack.org/openstack/ironic.git
The plain text file format is space separated and has four mandatory fields
optionally followed by fields which are type dependent::
*File : elements/custom-element/source-repository-pbr*
<name> <type> <destination> <location> [<ref>]
# <ref> is defined as "*" by default, although this behavior is deprecated.
# A value of "." extracts the entire contents of the tarball.
# A value of "*" extracts the contents within all its subdirectories.
# A value of a subdirectory path may be used to extract only its contents.
# A value of a specific file path within the archive is not supported.
pbr tar /usr/local/pbr http://tarballs.openstack.org/pbr/pbr-master.tar.gz .
``name``
Identifier for the source repository. Should match the file suffix.
diskimage-builder will then retrieve the sources specified and place them
at the directory \<destination\>
``type``
Format of the source. Either ``git``, ``tar``, ``package`` or ``file``.
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
``destination``
Base path to place sources.
DIB_REPOTYPE_<name> : change the registered type
DIB_REPOLOCATION_<name> : change the registered location
DIB_REPOREF_<name> : change the registered reference
``location``
Resource to fetch sources from. For ``git`` the location is cloned. For
``tar`` it is extracted.
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
``ref`` (optional). Meaning depends on the ``type``:
``file``: unused/ignored.
*As you can see above, the \<name\> of the repo is used in several bash
variables. In order to make this syntactically feasible, any characters not in
the set \[A-Za-z0-9_\] will be converted to \_*
``git``: a git reference to fetch. A value of "``*``" prunes and fetches all
heads and tags. Defaults to ``master`` if not specified.
*For instance, a repository named "diskimage-builder" would set a variable called
"DIB_REPOTYPE_diskimage_builder"*
``tar``:
| "``.``" extracts the entire contents of the tarball.
| "``*``" extracts the contents within all its subdirectories.
| A subdirectory path may be used to extract only its contents.
| A specific file path within the archive is **not supported**.
The lines in the source-repository scripts are eval'd, so they may contain
environment variables.
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
The ``package`` type indicates the element should install from packages onto
the root filesystem of the image build during the ``install.d`` phase. If the
element provides an <element-name>-package-install directory, symlinks will be
created for those scripts instead.
If you wish to build an image using code from a gerrit review, you can set
DIB_REPOLOCATION_<name> and DIB_REPOREF_<name> to the values given by gerrit in the
fetch/pull section of a review. For example:
``git`` and ``tar`` are treated as source installs. If the element provides an
<element-name>-source-install directory under it's ``install.d`` hook directory,
symlinks to the scripts in that directory will be created under ``install.d`` for
the image build.
DIB_REPOLOCATION_nova=https://review.openstack.org/openstack/nova
DIB_REPOREF_nova=refs/changes/72/61972/8
Additionally, the lines in the source-repository scripts are eval'd, so they
may contain environment variables.
Git sources will be cloned to \<destination\>
Tarballs will be extracted to \<destination\>.
The package type indicates the element should install from packages onto the
root filesystem of the image build during the install.d phase.
Git and Tarballs are treated as source installs. If the element provides an
<element-name>-source-install directory under it's install.d hook directory,
symlinks to the scripts in that directory will be created under install.d for
the image build. Alternatively for the package install type, if the element
provides an <element-name>-package-install directory, symlinks will be created
for those scripts instead.
For example, the nova element would provide:
For example, the nova element would provide::
nova/install.d/nova-package-install/74-nova
nova/install.d/nova-source-install/74-nova
source-repositories will create the following symlink for the package install
type:
type::
install.d/74-nova -> nova-package-install/74-nova
Or, for the source install type:
Or, for the source install type::
install.d/74-nova -> nova-source-install/74-nova
All other scripts that exist under install.d for an element will be executed as
All other scripts that exist under ``install.d`` for an element will be executed as
normal. This allows common install code to live in a script outside of
<element-name>-package-install or <element-name>-source-install.
@ -100,14 +80,86 @@ The repository names and types are written to an environment.d hook script at
01-source-repositories-environment. This allows later hook scripts during the
install.d phase to know which install type to use for the element.
An example of an element "custom-element" that wants to retrieve the ironic
source from git and pbr from a tarball would be:
*Element file: elements/custom-element/source-repository-ironic*::
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>``.
Override per source
-------------------
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 would override the ``<location>`` field and could set:
.. sourcecode:: sh
DIB_REPOLOCATION_ironic=git://localgitserver/ironic.git
*As you can see above, the \<name\> of the repo is used in several bash
variables. In order to make this syntactically feasible, any characters not in
the set \[A-Za-z0-9_\] will be converted to \_*
*For instance, a repository named "diskimage-builder" would set a variable called
"DIB_REPOTYPE_diskimage_builder"*
Alternatively if you would like to use the keystone element and build an image with
keystone from a stable branch *stable/grizzly* then you would set:
.. sourcecode:: sh
DIB_REPOREF_keystone=stable/grizzly
If you wish to build an image using code from a Gerrit review, you can set
``DIB_REPOLOCATION_<name>`` and ``DIB_REPOREF_<name>`` to the values given by
Gerrit in the fetch/pull section of a review. For example, setting up Nova with
change 61972 at patchset 8:
.. sourcecode:: sh
DIB_REPOLOCATION_nova=https://review.openstack.org/openstack/nova
DIB_REPOREF_nova=refs/changes/72/61972/8
Alternate behaviors
-------------------
Override git remote
^^^^^^^^^^^^^^^^^^^
The base url for all git repositories can be set by use of:
DIB_GITREPOBASE
``DIB_GITREPOBASE``
So setting DIB\_GITREPOBASE=https://github.com/ when the repo location is set
to http://git.openstack.org/openstack/nova.git will result in use of the
https://github.com/openstack/nova.git repository.
So setting ``DIB_GITREPOBASE=https://github.com/`` when the repo location is
set to http://git.openstack.org/openstack/nova.git will result in use of the
https://github.com/openstack/nova.git repository instead.
Disable external fetches
^^^^^^^^^^^^^^^^^^^^^^^^
When doing image builds in environments where external resources are not allowed,
it is possible to disable fetching of all source repositories by including an
element in the image that sets NO_SOURCE_REPOSITORIES=1 in an environment.d script.
element in the image that sets ``NO_SOURCE_REPOSITORIES=1`` in an
``environment.d`` script.