feat(github): validate-comment (#120)

github/validate-comment/README.md

@@ -0,0 +1,39 @@
+# <!--name-->github/validate-comment<!--/name-->
+
+[![usages](https://img.shields.io/badge/usages-white?logo=githubactions&logoColor=blue)](https://github.com/search?q=elastic%2Foblt-actions%2Fgithub%2Fvalidate-comment+%28path%3A.github%2Fworkflows+OR+path%3A**%2Faction.yml+OR+path%3A**%2Faction.yaml%29&type=code)
+
+<!--description-->
+Check whether the GitHub comment was triggered by a user with write permissions
+<!--/description-->
+
+## Inputs
+<!--inputs-->
+| Name | Description | Required | Default |
+|------|-------------|----------|---------|
+<!--/inputs-->
+
+## Exported Environment Variables
+
+| name       | description             |
+|------------|-------------------------|
+| `GIT_USER` | <p>Git username</p>     |
+| `GIT_EMAIL`| <p>Git email</p>        |
+
+## Usage
+
+<!--usage action="elastic/oblt-actions/**" version="env:VERSION"-->
+```yaml
+---
+name: Is GitHub comment allowed
+on:
+  issue_comment:
+    types: [created]
+jobs:
+  run-action-if-comment:
+    if: github.event.issue.pull_request && startsWith(github.event.comment.body, '/run-test')
+    runs-on: ubuntu-latest
+    steps:
+      - uses: elastic/oblt-actions/github/validate-comment@v1
+      # ...
+```
+<!--/usage-->

github/validate-comment/action.yml

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+name: 'github/validate-comment'
+
+description: Check whether the GitHub comment was triggered by a user with write permissions
+
+runs:
+  using: "composite"
+  steps:
+    - name: Is comment allowed?
+      uses: actions/github-script@v7
+      with:
+        script: |
+          // Report with a reaction that the event has been listened
+          await github.rest.reactions.createForIssueComment({
+            ...context.repo,
+            comment_id: context.payload.comment.id,
+            content: '+1',
+          })
+
+          const actorPermission = (await github.rest.repos.getCollaboratorPermissionLevel({
+            ...context.repo,
+            username: context.actor
+          })).data.permission
+          const isPermitted = ['write', 'admin'].includes(actorPermission)
+          if (!isPermitted) {
+            const errorMessage = 'Only users with write permission to the repository can run GitHub commands'
+            await github.rest.issues.createComment({
+              ...context.repo,
+              issue_number: context.issue.number,
+              body: errorMessage,
+            })
+            core.setFailed(errorMessage)
+            return;
+          }