Silver-Platter

Silver-Platter makes it possible to contribute automatable changes to source code in a version control system ("codemods" <https://github.com/jelmer/awesome-codemods>`_).

It automatically creates a local checkout of a remote repository, makes user-specified changes, publishes those changes on the remote hosting site and then creates a pull request.

In addition to that, it can also perform basic maintenance on branches that have been proposed for merging - such as restarting them if they have conflicts due to upstream changes.

Silver-Platter powers the Debian Janitor (https://janitor.debian.org/) and Kali Janitor (https://kali.janitor.org/). However, it is an independent project and can be used fine as a standalone tool. The UI is still a bit rough around the edges, I'd be grateful for any feedback from people using it - please file bugs in the issue tracker at https://github.com/jelmer/silver-platter/issues/new.

Getting started

To log in to a code-hosting site, use svp login:

svp login https://github.com/

The simplest way to create a change as a merge proposal is to run something like:

svp run --mode=propose ./framwork.sh https://github.com/jelmer/dulwich

where framwork.sh makes some modifications to a working copy and prints the commit message and body for the pull request to standard out. For example:

#!/bin/sh
sed -i 's/framwork/framework/' README.rst
echo "Fix common typo: framwork => framework"

If you leave pending changes, silver-platter will automatically create a commit and use the output from the script as the commit message. Scripts also create their own commits if they prefer - this is especially useful if they would like to create multiple commits.

Recipes

To make this process a little bit easier to repeat, recipe files can be used. For the example above, we could create a framwork.yaml with the following contents:

---
name: framwork
command: ./framwork.sh
mode: propose
merge-request:
  commit-message: Fix a typo
  description:
    markdown: |-
      I spotted that we often mistype *framework* as *framwork*.

To execute this recipe, run:

svp run --recipe=framwork.yaml https://github.com/jelmer/dulwich

See example.yaml for an example recipe with plenty of comments.

In addition, you can run a particular recipe over a set of repositories by specifying a candidate list. For example, if candidates.yaml looked like this:

---
- url: https://github.com/dulwich/dulwich
- url: https://github.com/jelmer/xandikos

then the following command would process each repository in turn:

svp run --recipe=framwork.yaml --candidates=candidates.yaml

Supported hosters

At the moment, the following code hosters are supported:

• GitHub
• Launchpad
• GitLab instances, such as Debian's Salsa or GNOME's GitLab

Working with Debian packages

Several common operations for Debian packages have dedicated subcommands under the debian-svp command. These will also automatically look up packaging repository location for any Debian package names that are specified.

• upload-pending: Build and upload a package and push/propose the changelog updates.
• run: Similar to svp run but specific to Debian packages: it ensures that the upstream and pristine-tar branches are available as well, can optionally update the changelog, and can test that the branch still builds.

Some Debian-specific example recipes are provided in examples/debian/:

• lintian-fixes.yaml: Run the lintian-brush command to fix common issues reported by lintian.
• new-upstream-release.yaml: Merge in a new upstream release.
• multi-arch-hints.yaml: Apply multi-arch hints.
• orphan.yaml: Mark a package as orphaned, update its Maintainer field and move it to the common Debian salsa group.
• rules-requires-root.yaml: Mark a package as "Rules-Requires-Root: no"
• cme.yaml: Run "cme fix dpkg", from the cme package.

debian-svp run takes package name arguments that will be resolved to repository locations from the Vcs-Git field in the package.

See debian-svp COMMAND --help for more details.

Examples running debian-svp:

# Create merge proposal running lintian-brush against Samba
debian-svp run --recipe=examples/lintian-brush.yaml samba

# Upload pending changes for tdb
debian-svp upload-pending tdb

# Upload pending changes for any packages maintained by Jelmer,
# querying vcswatch.
debian-svp upload-pending --vcswatch --maintainer [email protected]

# Import the latest upstream release for tdb, without testing
# the build afterwards.
debian-svp run --recipe=examples/debian/new-upstream-release.yaml \
    --no-build-verify tdb

# Apply multi-arch hints to tdb
debian-svp run --recipe=examples/debian/multiarch-hints.yaml tdb

The following environment variables are provided for Debian packages:

• DEB_SOURCE: the source package name
• DEB_UPDATE_CHANGELOG: indicates whether a changelog entry should be added. Either "leave" (leave alone) or "update" (update changelog).

Credentials

The svp hosters subcommand can be used to display the hosting sites that silver-platter is aware of:

svp hosters

And to log into a new hosting site, simply run svp login BASE-URL, e.g.:

svp login https://launchpad.net/

Exit status

svp run will exit 0 if no changes have been made, 1 if at least one repository has been changed and 2 in case of trouble.

Python API

Other than the command-line API, silver-platter also has a Python API. The core class is the Workspace context manager, which exists in two forms:

• silver_platter.workspace.Workspace (for generic projects)
• silver_platter.debian.Workspace (for Debian packages)

An example, adding a new entry to a changelog file in the dulwich Debian package and creating a merge proposal with that change:

from silver_platter.debian import Workspace
import subprocess

with Workspace.from_apt_package(package="dulwich") as ws:
    subprocess.check_call(['dch', 'some change'], cwd=ws.path)
    ws.commit()  # Behaves like debcommit
    ws.publish(mode='propose')