Fix XCom key handling when keys contain special characters like slash

[henry3260]

This PR picks up the work from @Brunda10 in PR #56042, which had become stale.

• Fixes 404 errors for XCom keys containing special characters (e.g., /).
• Keys are now URL-encoded (quoted) before being sent to the API.
• Keys are decoded (unquoted) when received from the API.
• Adds required unit tests to verify the fix, as requested in the original PR.

Closes: #55410

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[henry3260]

Nice!

It would be nice to add pytest.mark.parametrize with slash value key in task-sdk-integration-tests/tests/task_sdk_tests/test_xcom_operations.py tests.

Thanks!

Thanks for reviewing!

Slash keys aren’t supported today: the route pattern /{dag_id}/{run_id}/{task_id}/{key} treats {key} as a single path segment, so "folder/sub/value" splits into multiple segments and won’t match. Adding support means restructuring the routes (e.g. {key:path} plus reworking /item/{offset} and /slice), or switching to a query param (?key=). That’s a broader change, so I propose we keep the simple key test in this PR, optionally mark a slash-key test as xfail, and follow up with a dedicated issue/PR for proper support. If you prefer to fold the refactor into this PR, let me know—just want to confirm scope first.

[henry3260]

@henry3260 Do you mind rebasing to fix the conflicts. We can probably go ahead and merge, the PR is looking good.

Sure

[henry3260]

@henry3260 Do you mind rebasing to fix the conflicts. We can probably go ahead and merge, the PR is looking good.

All CI tests have passed. Ready for merge!

[pierrejeambrun]

Thanks for the PR.

[github-actions[bot]]

Backport successfully created: v3-1-test

Status	Branch	Result
✅	v3-1-test