meson/docs/markdown/Adding-new-projects-to-wrapdb.md

Adding new projects to WrapDB

How it works

Each wrap repository has a master branch with only one initial commit and no wrap files. And that is the only commit ever made on that branch.

For every release of a project a new branch is created. The new branch is named after the the upstream release number (e.g. 1.0.0). This branch holds a wrap file for this particular release.

There are two types of wraps on WrapDB - regular wraps and wraps with Meson build definition patches. A wrap file in a repository on WrapDB must have a name upstream.wrap.

Wraps with Meson build definition patches work in much the same way as Debian: we take the unaltered upstream source package and add a new build system to it as a patch. These build systems are stored as Git repositories on GitHub. They only contain build definition files. You may also think of them as an overlay to upstream source.

Whenever a new commit is pushed into GitHub's project branch, a new wrap is generated with an incremented version number. All the old releases remain unaltered. New commits are always done via GitHub merge requests and must be reviewed by someone other than the submitter.

Note that your Git repo with wrap must not contain the subdirectory of the source release. That gets added automatically by the service. You also must not commit any source code from the original tarball into the wrap repository.

Choosing the repository name

Wrapped subprojects are used much like external dependencies. Thus they should have the same name as the upstream projects.

NOTE: Repo names must fully match this regexp: [a-z0-9._]+.

If the project provides a pkg-config file, then the repository name should be the same as the pkg-config name. Usually this is the name of the project, such as libpng. Sometimes it is slightly different, however. As an example the libogg project's chosen pkg-config name is ogg instead of libogg, which is the reason why the repository is named plain ogg.

If there is no a pkg-config file, the name the project uses/promotes should be used, lowercase only (Catch2 -> catch2).

If the project name is too generic or ambiguous (e.g. benchmark), consider using organization-project naming format (e.g. google-benchmark).

How to contribute a new wrap

If the project already uses Meson build system, then only a wrap file

• upstream.wrap should be provided. In other case a Meson build definition patch - a set of meson.build files - should be also provided.

Request a new repository

Note: you should only do this if you have written the build files and want to contribute them for inclusion to WrapDB. The maintainers have only limited reesources and unfortunately can not take requests to write Meson build definitions for arbitrary projects.

The submission starts by creating an issue on the wrapdb bug tracker using Title and Description below as a template.

Title: new wrap: <project_name>

Description:

upstream url: <link_to_updastream>
version: <version_you_have_a_wrap_for>

Wait until the new repository or branch is created. A link to the new repository or branch will be posted in a comment to this issue. After this you can createa a merge request in that repository for your build files.

NOTE: Requesting a branch is not necessary. WrapDB maintainer can create the branch and modify the PR accordingly if the project repository exists.

Creating the wrap contents

Setting up the contents might seem a bit counterintuitive at first. Just remember that the outcome needs to have one (and only one) commit that has all the build definition files (i.e. meson.build and meson_options.txt files) and nothing else. It is good practice to have this commit in a branch whose name matches the release as described above.

First you need to fork the repository to your own page using GitHub's fork button. Then you can clone the repo to your local machine.

git clone git@github.com:yourusername/libfoo.git foo-wrap

Create a new branch for your work:

git checkout -b 1.0.0

If you are adding new changes to an existing branch, leave out the -b argument.

Now you need to copy the source code for the original project to this directory. If you already have it extracted somewhere, you'd do something like this:

cd /path/to/source/extract/dir
cp -r * /path/to/foo-wrap

Now all the files should be in the wrap directory. Do not add them to Git, though. Neither now or at any time during this process. The repo must contain only the newly created build files.

New release branches require an upstream.wrap file, so create one if needed.

${EDITOR} upstream.wrap

The file format is simple, see any existing wrapdb repo for the content. The checksum is SHA-256 and can be calculated with the following command on most unix-like operating systems:

sha256sum path/to/libfoo-1.0.0.tar.gz

Under macOS the command is the following:

shasum -a 256 path/to/libfoo-1.0.0.tar.gz

Next you need to add the entries that define what dependencies the current project provides. This is important, as it is what makes Meson's automatic dependency resolver work. It is done by adding a provide entry at the end of the upstream.wrap file. Using the Ogg library as an example, this is what it would look like:

[provide]
ogg = ogg_dep

The ogg part on the left refers to the dependency name, which should be the same as its Pkg-Config name. ogg_dep on the right refers to the variable in the build definitions that provides the dependency. Most commonly it holds the result of a declare_dependency call. If a variable of that name is not defined, Meson will exit with a hard error. For further details see the main Wrap manual.

Now you can create the build files and work on them until the project builds correctly.

${EDITOR} meson.build meson_options.txt

When you are satisfied with the results, add the build files to Git and push the result to GitHub.

<verify that your project builds and runs>
git add upstream.wrap meson.build
git commit -a -m 'Add wrap files for libfoo-1.0.0'
git push -u origin 1.0.0

Now you should create a pull request on GitHub. Try to create it against the correct branch rather than master (1.0.0 branch in this example). GitHub should do this automatically.

If the branch doesn't exist file a pull request against master. WrapDB maintainers can fix it before merging.

If packaging review requires you to do changes, use the --amend argument to commit so that your branch will continue to have only one commit.

${EDITOR} meson.build
git commit -a --amend
git push --force

Request a new release version to an existing repository

Adding new releases to an existing repo is straightforward. All you need to do is to follow the rules discussed above but when you create the merge request, file it against the master branch. The repository reviewer will create the necessary branch and retarget your merge request accordingly.

What is done by WrapDB maintainers

mesonwrap tools must be used for the tasks below.

Adding new project to the Wrap provider service

Each project gets its own repo. It is initialized like this:

mesonwrap new_repo --homepage=$HOMEPAGE --directory=$NEW_LOCAL_PROJECT_DIR $PROJECT_NAME

The command creates a new repository and uploads it to GitHub.

--version flag may be used to create a branch immediately.

Adding a new branch to an existing project

Create a new branch whose name matches the upstream release number.

git checkout master
git checkout -b 1.0.0
git push origin 1.0.0
(or from GitHub web page, remember to branch from master)

Branch names must fully match this regexp: [a-z0-9._]+.

Changes to original source

The point of a wrap is to provide the upstream project with as few changes as possible. Most projects should not contain anything more than a few Meson definition files. Sometimes it may be necessary to add a template header file or something similar. These should be held at a minimum.

It should especially be noted that there must not be any patches to functionality. All such changes must be submitted to upstream. You may also host your own Git repo with the changes if you wish. The Wrap system has native support for Git subprojects.

Reviewing wraps

See Wrap review guidelines, especially the part about tooling that you can use to check for the most common problems yourself. Fixing all issues reported by the tool is a mandatory requirement for getting your MR accepted, so doing this proactively makes the review process smoother.