feat: add repology datasource

[ppmathis]

Description

This pull request introduces Repology as a data source to Renovate. It is not directly used by any manager and instead meant to be combined with the recently added regex managers. This unlocks the possibility of automatically updating system packages in Dockerfiles. Closes #5672.

Implementation

This data source uses the recently introduced tools/project-by API endpoint on Repology to lookup a package. It will first attempt to match a binary package, as this is almost always the desired package type. If no matching binary package can be found, a second lookup for a source package will be automatically made. All results are cached for 60 minutes based on the passed repository and package name.

Usage

As Repology supports many different repositories, the lookupName of a dependency must contain both the repository name as well as the binary or source package name, separated by a slash. This means that alpine_3_12/gcc results in looking up a binary or source package named gcc within the alpine_3_12 repository.

A list of all supported repositories can be found on the Repology homepage, where the URLs https://repology.org/repository/<repository name> contain the proper repository ID. E.g. if you click on Alpine Linux 3.12, the URL will be https://repology.org/repository/alpine_3_12, revealing the repository ID alpine_3_12.

Usage Example

The following snippet shows a minimal example when using the regex manager suggested in the docs section Advanced Capture:

# renovate: datasource=repology depName=alpine_3_12/gcc versioning=loose
ENV GCC_VERSION="9.3.0-r2"

Now whenever the OS package for gcc of Alpine Linux 3.12 is being updated, Renovate will automatically update this value to the newest version. It is often recommended to use the loose versioning scheme for system packages.

Real Word Example

Dockerfile Snippets:

• https://github.com/snapserv/docker-alpine/blob/ebf79a43143867bbc125aa1f55abd819e0740fb5/Dockerfile#L3-L6
• https://github.com/snapserv/docker-alpine/blob/ebf79a43143867bbc125aa1f55abd819e0740fb5/Dockerfile#L24-L27

Renovate Config: https://github.com/snapserv/renovate-config/blob/b35b0535109403d3684c86aaf609a39eb4de4985/docker.json#L32-L41
Example Pull Request: https://github.com/snapserv/docker-alpine/pull/8

[rarkins]

@ppmathis this is great. Can you add a readme.md file into this folder? Ideally it should contain enough information that future users of this datasource can know how to use it with the regex manager without referring to source code or this PR's description. We can update our doc generating scripts so that the content of it is added to docs.renovatebot.com later.

[ppmathis]

@rarkins Good idea, I've created a readme.md within lib/datasource/repology which should hopefully explain the most important aspects of this datasource. Any thoughts?

@viceice Thank you for the quick code review. All the requested changes should have now been implemented accordingly.

UPDATE: Just noticed that JSON.parse is no longer needed after switching to httpMock as the response body is always a string. I've changed this accordingly and pushed an updated commit.

[JamieMagee]

@ppmathis Sorry I completely missed this PR, but this is excellent work! I know you've been looking at this for a long time, and I think it's going to really open up a lot of possibilities 🎉

[renovate-release]

🎉 This PR is included in version 21.4.0 🎉

The release is available on:

• GitHub release
• 21.4.0

Your semantic-release bot 📦🚀