feat: add MySQL command support

[enbiyagoral]

This PR adds MySQL connection support to the Boundary CLI. Users can now securely and easily connect to MySQL targets using the boundary connect mysql command.

What’s Added?

• boundary connect mysql command
• Credential and target support for MySQL
• Required tests and documentation updates

Related Issue

Closes #5740

Testing

• All tests passed successfully
• MySQL connection tests were performed

Images

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Note: This PR follows the same architecture and UX as the existing helper command for PostgreSQL.

[hashicorp-cla-app]

All committers have signed the CLA.

[enbiyagoral]

@bgajjala8 @RyanDerr @johanbrandhorst

Hi! I've addressed all the review feedback:

1. ✅ Now using --defaults-file instead of direct password in args
2. ✅ --defaults-file is now the first argument
3. ✅ Added -p flag when no password provided for prompt
4. ✅ Followed the same pattern as PostgreSQL implementation

Ready for re-review! Thank you for the guidance.

[johanbrandhorst]

This is really cool, thank you! There are a few things we'll need to update before we can merge this:

1. We will need to add some documentation to the website, so users can find this new command. Please add a new file called mysql.mdx to https://github.com/hashicorp/boundary/tree/main/website/content/docs/commands/connect where the other connect helpers are documented. You should be able to base it on the postgres one. Also update the index.mdx document with references to the new document.
2. We will need to add some tests for this functionality. Fortunately, it's pretty easy to run mysql for testing purposes, just as we do with postgresql. I think we could add a StartMysql helper to https://github.com/hashicorp/boundary/blob/main/testing/internal/e2e/infra/docker.go, then create a test similar to https://github.com/hashicorp/boundary/blob/main/testing/internal/e2e/tests/base_plus/target_tcp_connect_postgres_test.go that will connect to the MySQL instance and run some commands.
3. We'll need to update the CHANGELOG.md with this new feature :). Please follow the existing patterns.

Again, thanks for your contribution to Boundary, this is really exciting!

[enbiyagoral]

@bgajjala8 @johanbrandhorst - Updated with all requested changes:

Security fixes:

• Switched to --defaults-file approach ✅
• Password prompting with -p flag ✅

Documentation & Testing:

• Added MySQL documentation page ✅
• Added comprehensive tests ✅
• Added StartMysql helper ✅

Ready for re-review!

[enbiyagoral]

Thanks for the feedback! I've updated the test to be completely self-contained - it now starts its own MySQL container using infra.StartMysql(), eliminates any dependency on environment variables, and actually tests the functionality by executing real MySQL commands (SHOW TABLES, SELECT DATABASE()) through the boundary connect mysql command while validating the connection works end-to-end with proper cleanup of all Docker resources.

[johanbrandhorst]

Thanks for your patience. I think the test may fail on some machines because the MySQL output is not accurate. Furthermore, the way our CI is set up at the moment makes it impossible for us to run all the tests against this PR, so I was wondering if I could have your consent for us to recreate this contribution in a PR created by a HashiCorp IBM employee so the CI will run? You will still have the commit credit of course.

[enbiyagoral]

Thanks for your patience. I think the test may fail on some machines because the MySQL output is not accurate. Furthermore, the way our CI is set up at the moment makes it impossible for us to run all the tests against this PR, so I was wondering if I could have your consent for us to recreate this contribution in a PR created by a HashiCorp IBM employee so the CI will run? You will still have the commit credit of course.

I’m happy to give my consent. Please feel free to proceed, and I appreciate you keeping the commit credit. Let me know if I can assist further.

[johanbrandhorst]

This looks good to me now! As discussed, lets have @bgajjala8 recreate the PR so we can run CI on it. Thanks for your contribution! We can close this PR out once the other one has been merged.

[enbiyagoral]

Sounds great — thanks for the review and the support @bgajjala8 @johanbrandhorst! Looking forward to the merged version.

[bgajjala8]

@enbiyagoral This feature has been merged! 😄 Thanks for your contribution to Boundary, this was really exciting!

Closing this PR out now
CC: @johanbrandhorst @RyanDerr

[enbiyagoral]

Thanks so much everyone for the help and reviews (@johanbrandhorst, @bgajjala8 )— this was my first contribution to Boundary, and it was a great experience! 🙌 Looking forward to future contributions