Allow Renovate to migrate its own configuration

[SebastianGoeb]

What would you like Renovate to be able to do?

It would be cool if Renovate could post config-migration PRs for its own config.json/js in the same way that it can for renovate.json of managed repositories.

If you have any ideas on how this should be implemented, please tell us here.

We use self-hosted Renovate running in a GitLab-CI Repo/Pipeline. Currently "Config needs migrating ..." logs aren't very useful because they end up in Renovate's own pipeline logs, which we don't usually check (it's supposed to be automated, right).

I was really hoping the configMigration feature could turn these log messages about config.js needing migrating into a PR that would update config.js. Unfortunately, this seems to only be available for the repository.json files of the managed repositories.

From what I can gather, Renovate currently uses its config migration code in two separate places:

1. from workers/global/config/parse/file.ts

     const { isMigrated, migratedConfig } = migrateConfig(config);
     if (isMigrated) {
       logger.warn(
         { originalConfig: config, migratedConfig },
         'Config needs migrating'
       );
       config = migratedConfig;
     }
   

   which operates on config.js and results in the log message "Config needs migrating" or [nothing].
2. workers/repository/config-migration/branch/migrated-data.ts

   // get migrated config
   const { isMigrated, migratedConfig } = migrateConfig(configFileParsed);
   if (!isMigrated) {
     return null;
   }
   

   which operates on renovate.json and results in a migration PR or the debug message "checkConfigMigrationBranch() Config does not need migration".

Maybe these usages could be unified somehow to allow both to produce config-migration PRs?

I suppose, I could also extract the shared settings into another, separate repository, also managed by renovate. This renovate.json could then be used by all repositories, including renovate itself. But that seems quite complicated (if including renovate.json into config.js is even permitted, not sure...). In any case, being able to migrate config.js too seems like a useful feature to me.

Is this a feature you are interested in implementing yourself?

No

[viceice]

that's a lot more complicated that you think

[SebastianGoeb]

that's a lot more complicated that you think

Is it? Renovate already produces Config needs migrating: oldConfig: {}, migratedConfig: {}, so essentially a diff. I haven't dug deep enough into the source, but I imagine the problem stems mostly from:

1. this probably (?) being the final, composite configuration that comes out of module.exports = ..., with includes, functions, etc. all resolved
2. config.js being a .js file, which could range from a simple json wrapper with some env replacements (that's what we do) to a complex, dynamic configuration possibly pulling parameters from remote apis (very clearly un-updatable).

Maybe, instead of having to reverse-engineering the .js to update it, a compromise could be to post a Draft-PR with the json and/or diff as a comment/thread/suggestion. The actual work of updating the config.js could be left to the reviewer, making this PR more of a notification that something needs to be done, rather than outright doing it, i.e. half-automated.

To be honest, I would already be very happy with simple notification-style PR, where I still have to do the work. The current problem is mainly that necessary changes go completely unnoticed, not that it's too much work to make the changes.

My original plan was to parse the JSON from the log and post that as a PR. Which is essentially the same thing, just as a hacky workaround instead of a native feature.

[HonkingGoose]

This issue may be a duplicate of this earlier one? Or maybe there are key differences between the issues, and we should keep both... 🙈

• Enable config migration by default #16359

[rarkins]

Duplicate of #1502

Fixed by #15122