使用Python编写的Google Cloud Function触发DAG时出现404错误求助

开发者阿泽

2026-8-25

解决GCP Cloud Function触发Airflow DAG时的404错误

我在GCP上运行Python编写的Cloud Function，尝试触发Airflow DAG，严格按照官方文档操作，但持续收到Airflow返回的404错误，错误日志如下：

EDT

gcs-dag-trigger-function

68hsnlvog0g6
Traceback (most recent call last):
  File "/layers/google.python.pip/pip/lib/python3.9/site-packages/flask/app.py", line 2073, in wsgi_app
    response = self.full_dispatch_request()
  File "/layers/google.python.pip/pip/lib/python3.9/site-packages/flask/app.py", line 1518, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/layers/google.python.pip/pip/lib/python3.9/site-packages/flask/app.py", line 1516, in full_dispatch_request
    rv = self.dispatch_request()
  File "/layers/google.python.pip/pip/lib/python3.9/site-packages/flask/app.py", line 1502, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
  File "/layers/google.python.pip/pip/lib/python3.9/site-packages/functions_framework/__init__.py", line 171, in view_func
    function(data, context)
  File "/workspace/main.py", line 48, in trigger_dag
    make_iap_request(
  File "/workspace/main.py", line 87, in make_iap_request
    raise Exception(
Exception: Bad response from application: 404 / {'Date': 'Fri, 15 Jul 2022 16:25:22 GMT', 'Content-Type': 'text/html; charset=utf-8', 'Vary': 'Accept-Encoding', 'Server': 'gunicorn', 'X-Robots-Tag': 'noindex, nofollow', 'Set-Cookie': 'session=d8fb37f6-bd2d-4a2c-8abc-e528eadc9ac3.hUuadQnCRiJzbuufKObZIMtsTL8; Expires=Sun, 14-Aug-2022 16:25:22 GMT; HttpOnly; Path=/; SameSite=Lax', 'Content-Encoding': 'gzip', 'Via': '1.1 google', 'Alt-Svc': 'h3=":443"; ma=2592000,h3-29=":443"; ma=2592000,h3-Q050=":443"; ma=2592000,h3-Q046=":443"; ma=2592000,h3-Q043=":443"; ma=2592000,quic=":443"; ma=2592000; v="46,43"', 'Transfer-Encoding': 'chunked'} / '

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Airflow 404</title>
    <link rel="icon" type="image/png" href="/static/pin_32.png">
  </head>
  <body>
    <div style="font-family: verdana; text-align: center; margin-top: 200px;">
      <img src="/static/pin_100.png" width="50px" alt="pin-logo" />
      <h1>Airflow 404</h1>
      <p>Page cannot be found.</p>
      <a href="/">Return to the main page</a>
      <p>3405c1ef5ce7</p>
    </div>
  </body>
</html>'

以下是排查和解决方向：

核对Airflow API路径与版本匹配
Airflow 1.x和2.x的DAG触发API路径完全不同：
- 2.x版本用/api/v1/dags/<DAG_ID>/dagRuns
- 1.x版本用/api/experimental/dags/<DAG_ID>/dag_runs
  很多404都是因为硬套了错误版本的API路径，先确认你的Airflow版本，再修正请求路径。
检查DAG ID的准确性
Airflow对DAG ID的匹配是严格区分大小写和符号的，确保Cloud Function代码里写的DAG ID和Airflow UI里显示的完全一致，比如不要把my_dag写成My_Dag或者my-dag。
验证IAP目标URL和请求完整路径
如果通过IAP访问Airflow，确保IAP保护的是Airflow的根域名，且Cloud Function里的请求URL是完整的根域名加API路径，比如https://your-airflow-url.com/api/v1/dags/your-dag-id/dagRuns，不要漏掉根域名或者写错路径层级。
确认Airflow API未被禁用
对于Airflow 2.x，默认API是启用的，但如果自定义了webserver_config.py，要确保ENABLE_API = True；1.x版本要确认api_enabled配置为True，避免API端点被关闭。
直接测试API端点
绕过Cloud Function，用curl或Postman带上正确的IAP认证令牌直接访问Airflow API端点，确认端点本身是可访问的，排除Cloud Function代码之外的问题。示例命令：
```
curl -H "Authorization: Bearer <你的IAP令牌>" https://your-airflow-url.com/api/v1/dags/your-dag-id/dagRuns
```

内容的提问来源于stack exchange，提问作者DamianO