Add support for updating dependencies in target files

[laeubi]

The eclipse-pde target files (extension .target, content is xml) supports for a while to also mention maven dependencies.

This enhances the file fetcher to scan for target files in a repository and the file parser to parse any maven type location.

Fix #4682

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I'm creating this as a draft as it is missing a test case, this is my first time using ruby, so any help / hints would be appreciated.

[deivid-rodriguez]

Hi @laeubi, thanks for working on this. Regarding test cases, I recommend you inspire on existing test case. For example, you can change any of the existing selectors to something incorrect, and see which tests fail (hopefully, otherwise those selectors would be uncovered by tests... 😅). That should give you the relevant tests covering the implementation of those selectors that you can use as an inspiration.

[mjmeijer]

Unfortunately Github doesn't have #likes so I just post this comment as token of appreciation

[yeikel]

Unfortunately Github doesn't have #likes so I just post this comment as token of appreciation

You have reactions and that's pretty close 😄

[laeubi]

I rebased now on current main branch and set this to "Ready For Review", I have also tried to adapt one of the test-cases to target files, would be good to get a feedback from a maintainer if I'm on the right track.

[jurre]

Thanks for working on this! Overall I think the PR looks good, but I don't know much about eclipse target files and their format, do you have any docs that you'd recommend so I can read up on it a bit?

[laeubi]

@jurre first, feel free to ask any question about the format I can provide examples/insights if needed (I'm just a total newbie on ruby what makes it quite hard to adjust things).

There is some official documentation here:
https://help.eclipse.org/latest/index.jsp?topic=/org.eclipse.pde.doc.user/concepts/target.htm

but it is all a bit generic as usually users use the UI and do not really fiddle around with the details of serialization format, but it is also quite simple:

1. File format is XML
2. Root element is <target> that contains among others an element <locations> that has 0..n elements named <location>, each location has a type attribute, where only the type Maven is relevant here, a quite complex example can be found here: https://github.com/eclipse-m2e/m2e-core/blob/master/target-platform/target-platform.target, while the PR contains one reduced to the bare minimum: https://github.com/dependabot/dependabot-core/blob/54918367133820e94fbae4a332ae51d335e874ac/maven/spec/fixtures/target-files/example.target
3. As one can see, a target file might contain other things (like pom.xml), but for this purpose one can completely ignore that, the only relevant part is what an XPath of dependencies > dependency would select

[jurre]

Thanks! I notice the Maven tests and the linter are failing, would you mind taking a look at those?

[laeubi]

Thanks! I notice the Maven tests and the linter are failing, would you mind taking a look at those?

I'll try to look at it, but as said my ruby skills are quite limited so I first need to understand how all these works, if someone mor familiar with rubby could take a look and maybe give some hints it would be helpfull!

[laeubi]

Thanks! I notice the Maven tests and the linter are failing, would you mind taking a look at those?

@jurre I now was able to fix the issue with the test and also other checks are all green now so I think it would be ready for review.

[laeubi]

@jurre what would be the next steps for this to become merged?

[jurre]

@laeubi someone on my team will deploy the changes to production, monitor to ensure they don't introduce regressions and then merge the changes in

[HannesWell]

@laeubi someone on my team will deploy the changes to production, monitor to ensure they don't introduce regressions and then merge the changes in

Is there an update how it is working? :)

[jurre]

These changes have not been deployed yet, so no update available, hoping someone will get to it soon 👍

[HannesWell]

These changes have not been deployed yet, so no update available, hoping someone will get to it soon 👍

Are there any updates yet? :)

[HannesWell]

These changes have not been deployed yet, so no update available, hoping someone will get to it soon 👍

Can you give us any update on this? It would be really nice to have this. :)

[tivervac]

@jurre Can this be deployed now? Anything we can help with?

[abdulapopoola]

@tivervac , if you could help with resolving the conflicts, we can take a stab at getting it merged. Thanks.

[HannesWell]

@tivervac , if you could help with resolving the conflicts, we can take a stab at getting it merged. Thanks.

@laeubi is probably the right one to resolve the conflicts.