Issue Summary

With the current limitation to our webhook service. Merging a pull request with a large commit message or description fails to trigger an automatic build.

Steps to Reproduce

1. Configure bitbucket-pipelines.yml file to trigger a build when a pull request is merged to target branch
2. Open a pull request with a large commit message (e.g. 4K lines) or description
3. Merge the pull request

Expected Results

• Upon merging the pull request a build should automatically trigger on the target branch
• Customers should be notified that the payload is too large and has failed to trigger an automatic build. Doing so will provide a better experience overall. At the moment, there is no indication of what a build was not triggered when customers expect a build to trigger automatically.

Actual Results

• Build is not triggered on the target branch
• No indication into why the build was not triggered automatically
• This is caused by "Webhook payload is limited to 256 KB. Webhooks may silently fail to trigger if their payload is too large." - Reference: Troubleshooting webhooks

Workaround

Manually trigger build on the branch: Navigate to the "Branches" page, then click on the triple dots (...) at the end of the branch, and then "Run pipelines for a branch".