feat(integration): Add endpoint to validate a manually entered channel

[priscilawebdev]

Problem
The Slack API has some limitations (see the PR discussion). We list up to 1,000 channels in the dropdown, but users might not find the one they want. To address this, we will allow users to manually enter a channel. If the channel was typed instead of selected from the list, we want to validate it on the component’s onBlur event.

Solution
We’re introducing a separate endpoint specifically for channel validation, since the form might not be complete and we cannot fire the same request used when submitting the form.

This validation may not be necessary for MS Teams or Discord, but we can include it for consistency.

Contributes to https://linear.app/getsentry/issue/TET-1229/implement-dropdown-or-validation-for-slack-field

[linear]

TET-1229 Implement dropdown or validation for Slack field

[codecov]

Codecov Report

❌ Patch coverage is 92.00000% with 4 lines in your changes missing coverage. Please review.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...oints/organization_integration_channel_validate.py	91.83%	4 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #101508      +/-   ##
===========================================
+ Coverage   79.87%    80.99%   +1.11%     
===========================================
  Files        8697      8705       +8     
  Lines      386780    386842      +62     
  Branches    24514     24471      -43     
===========================================
+ Hits       308958    313306    +4348     
+ Misses      77474     73185    -4289     
- Partials      348       351       +3     

[leeandher]

Looks great! Minor comments, but logically looks excellent, great tests too 🔥

[leeandher]

I don't think we need this large wrapping try/except, If there are individual parts we worry about failing or timing out (maybe the slack util get_channel_id, and the other equivalents) then we can just wrap those portions so it's easier to understand what we're worrying about breaking.

That said anything that isn't an API call out to an integration seems super straight forward to me so I don't think this is necessary!

[priscilawebdev]

Thanks for the feedback! I updated the code so it no longer exposes raw responses, filters out known exceptions (ApiError, ValidationError, etc.), and uses sentry_sdk.capture_exception just for unexpected errors. I kept a single try/except around everything for simplicity - hope that is fine!

[github-actions]

🚨 Warning: This pull request contains Frontend and Backend changes!

It's discouraged to make changes to Sentry's Frontend and Backend in a single pull request. The Frontend and Backend are not atomically deployed. If the changes are interdependent of each other, they must be separated into two pull requests and be made forward or backwards compatible, such that the Backend or Frontend can be safely deployed independently.

Have questions? Please ask in the #discuss-dev-infra channel.

[sentry]

Issues attributed to commits in this pull request

This pull request was merged and Sentry observed the following issues:

• ‼️ SlackApiError: The request to the Slack API failed... in prod

• ‼️ SlackApiError: The request to the Slack API failed... in prod