Consider providing an option to warn users about read-only source files when dryRun feature is used

[gnsuryan]

When I run open-rewrite to migrate source files, and if a particular source file has read-only permissions (at the OS level), then I see that the mvn rewrite:run command fails with the following error:

[WARNING] Estimate time saved: 1h 50m
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 16.803 s
[INFO] Finished at: 2025-02-11T08:19:46Z
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.openrewrite.maven:rewrite-maven-plugin:6.1.0:run (default-cli) on project spring-petclinic: Execution default-cli of goal org.openrewrite.maven:rewrite-maven-plugin:6.1.0:run failed: Unable to rewrite source files: /scratch/user/demo/spring-petclinic-migration/src/main/java/org/springframework/samples/petclinic/visit/Visit.java -> [Help 1]

Please consider providing an option to warn the users about the read-only files when the dryRun feature is used
(mvn rewrite:dryRun)

Currently, I don't see any warnings/failures when read-only files are encountered when dryRun feature is used.

Thanks.

[timtebeek]

Hi @gnsuryan ; I don't quite see a reason to warn on read only files for dryRun specifically. That is intended to only create a patch file, and as such need not modify your sources, so also should not have an issue with read only files. Maven 4 will also have an option to fail the build if any warnings are produced, which would further complicate a seemingly unnecessary warning. I'd lean towards not adding such a feature.

What are your thoughts here? Why would it be an issue for dryRun in your case?

[gnsuryan]

Hi @timtebeek

Thank you for the quick response.

The reason, I thought dryRun would be a good option to detect and warn users, about read-only source files, which may under go changes when we eventually use the mvn rewrite:run command, was the fact that during a migration activity using open-rewrite tool, I had downloaded the source files from a perforce repository, where few of the source and configuration files were read-only while others had write permissions. When I ran the open-rewrite command to perform the migration, I ended up facing errors in cases, where the source files were read-only and this lead to partial migration. I tried fixing the errors, and re-ran the open-write command but ended up with more issues, leading to confusion.

So, I thought, since dryRun is a feature, where none of the source/configuration files get modified, it may be the best possible way to detect a read-only file and warn the users, to avoid failures when the user actually uses the mvn rewrite:run command.

Definitely this is a not a BUG/issue, but a nice to have feature, that can provide value add to the open-rewrite tool.

Thanks.

[timtebeek]

Thanks for the additional context; my expectation would be that you run rewrite:dryRun, and then git apply the .patch file it produces; That way you'll get notified about any write issues at that stage, and can alert the users as needed.

Others might have a different workflow, for instance running a dryRun on a CI environment where it's perfectly fine to have read only source files. As such I don't think it makes sense for us to report a warning in those cases, especially with that eye towards Maven 4.

I will however monitor further replies and comments here such that if more demand for this pops up in the future we can reevaluate then. Thanks!