initial commit

.gitignore

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+.vscode

README.md

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+# Github Action Merge Dependabot
+
+This action automatically merges dependabot PRs.
+
+## Inputs
+
+### `GITHUB_TOKEN`
+
+**Required** A github token.
+
+## Example usage
+
+```yml
+name: CI
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      ...
+
+  automerge:
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: salmanm/github-action-merge-dependabot@v1
+        if: ${{ github.actor == 'dependabot[bot]' && github.event_name == 'pull_request' }}
+        with:
+          github-token: ${{secrets.github_token}}
+```

action.yml

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+name: "Github Action Merge Dependabot"
+description: "Automatically merge dependabot PRs"
+inputs:
+  GITHUB_TOKEN:
+    description: "A GitHub token."
+    required: true
+runs:
+  using: "node12"
+  main: "index.js"

index.js

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+const core = require('@actions/core')
+const github = require('@actions/github')
+
+const GITHUB_TOKEN = core.getInput('github-token', { required: true })
+
+const getMergeMethod = (repo) => {
+  if (repo.allow_merge_commit) return 'merge'
+  if (repo.allow_squash_merge) return 'squash'
+  return 'rebase'
+}
+
+async function run () {
+  try {
+    const octokit = github.getOctokit(GITHUB_TOKEN)
+
+    const { repository, pull_request: pr } = github.context.payload
+    const owner = repository.owner.login
+    const repo = repository.name
+    const prNumber = pr.number
+
+    const isDependabotPR = pr.user.login === 'dependabot[bot]'
+
+    if (!isDependabotPR) {
+      return console.log('Unable to merge')
+    }
+
+    await octokit.pulls.createReview({
+      owner,
+      repo,
+      pull_number: prNumber,
+      event: 'APPROVE'
+    })
+
+    await octokit.pulls.merge({
+      owner,
+      repo,
+      pull_number: prNumber,
+      merge_method: getMergeMethod(pr.head.repo)
+    })
+  } catch (error) {
+    core.setFailed(error.message)
+  }
+}
+
+run()