GitHub Actions用服务密钥认证Google Cloud报错：JSON解析异常

运行GitHub Action时触发报错：

Error: google-github-actions/auth failed with: retry function failed after 1 attempt: failed to parse service account key JSON credentials: unexpected token  in JSON at position 0

服务账号密钥JSON格式（已脱敏）：

{
  "type": "service_account",
  "project_id": "",
  "private_key_id": "",
  "private_key": "-----BEGIN PRIVATE KEY-----\n-----END PRIVATE KEY-----\n",
  "client_email": "",
  "client_id": "",
  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
  "token_uri": "https://oauth2.googleapis.com/token",
  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
  "client_x509_cert_url": ""
}

Workflow配置片段：

- id: 'auth'
      name: 'Authenticate to Google Cloud'
      uses: 'google-github-actions/auth@v1'
      with:
        credentials_json: $GOOGLE_CREDENTIALS
    - id: 'upload-file'
      name: 'Upload report to Google Cloud'
      uses: 'google-github-actions/upload-cloud-storage@v0'
      with:
        path:  $GITHUB_WORKSPACE/mochawesome-report
        destination: api-test-results
        parent: false
        glob: '*.html'
    - uses: 'google-github-actions/upload-cloud-storage@v0'
      if: always()
      env:
        SLACK_URL: ${{ secrets.SLACK_URL }}
        GOOGLE_CREDENTIALS: ${{ secrets.GOOGLE_CREDENTIALS }}

问题原因及解决方法 #

• 核心原因：认证步骤中引用GitHub Secret的方式错误。credentials_json: $GOOGLE_CREDENTIALS没有使用GitHub Secrets的正确语法，导致实际传入的不是完整的服务账号密钥JSON内容，而是空值或无效字符串，JSON解析器在位置0就遇到意外字符，触发报错。

• 解决方法：将认证步骤里的$GOOGLE_CREDENTIALS替换为${{ secrets.GOOGLE_CREDENTIALS }}，正确引用GitHub Secret：

  - id: 'auth'
    name: 'Authenticate to Google Cloud'
    uses: 'google-github-actions/auth@v1'
    with:
      credentials_json: ${{ secrets.GOOGLE_CREDENTIALS }}
  

• 额外优化：后面的upload-cloud-storage步骤不需要再设置GOOGLE_CREDENTIALS环境变量，因为auth步骤已经完成认证并设置了后续步骤可用的凭据，多余的设置可以删除，避免不必要的混淆。

内容的提问来源于stack exchange，提问作者George