Commenting on Pull Requests in GitHub Actions opensearch
The OpenSearch API specification is authored in OpenAPI and used to auto-generate OpenSearch language clients. I wanted to know how much of the API was described in it vs. the actual API implemented in the default distribution of OpenSearch that includes all plugins. To do so, I have exposed an iterator over REST handlers in OpenSearch core, and wrote a plugin that rendered a very minimal OpenAPI spec at runtime. All that was left was to compare the manually authored OpenAPI spec in opensearch-api-specification to the runtime one, added in opensearch-api-specification#179. The comparison workflow output a total and relative number of APIs described.
To surface this information in pull requests I wanted to add a comment in the API coverage workflow. This required a PAT token, so I initially authored that workflow with pull_request_target in opensearch-api-specification#196.
This is actually insecure because we run a JavaScript tool to generate the API spec with source code coming from the pull request, and a user can execute arbitrary code this way and gain access to the secure token. One solution is to run the tool from main, but we can do better.
