在 Kube.netes 中启动容器时出错，但不是 docker-compose

Question

我的容器使用 docker-compose 运行良好。但是一旦我在 Kube.netes 上应用我的部署，它每次都会因相同的错误而失败。 不管我怎么努力。 我被卡住了，希望得到一些输入/帮助。

我不知道如何调试这个。 Kube.netes 有点新。 所以如果有人可以指导我，我可以尝试调试它。

错误堆栈跟踪如下：

Running migration with alembic
INFO  [src.core.config] value for BACKEND_CORS_ORIGINS= ['http://localhost:3000', 'http://localhost:8001']
Traceback (most recent call last):
  File "pydantic/env_settings.py", line 197, in pydantic.env_settings.EnvSettingsSource.__call__
  File "pydantic/env_settings.py", line 131, in pydantic.env_settings.Config.parse_env_var
  File "/usr/local/lib/python3.9/json/__init__.py", line 346, in loads
    return _default_decoder.decode(s)
  File "/usr/local/lib/python3.9/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())   
  File "/usr/local/lib/python3.9/json/decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

The above exception was the direct cause of the following exception:

Traceback (most recent call last):   
  File "/usr/local/bin/alembic", line 8, in <module>
    sys.exit(main())   
  File "/usr/local/lib/python3.9/site-packages/alembic/config.py", line 590, in main
    CommandLine(prog=prog).main(argv=argv)
  File "/usr/local/lib/python3.9/site-packages/alembic/config.py", line 584, in main
    self.run_cmd(cfg, options)
  File "/usr/local/lib/python3.9/site-packages/alembic/config.py", line 561, in run_cmd
    fn(
  File "/usr/local/lib/python3.9/site-packages/alembic/command.py", line 322, in upgrade
    script.run_env()
  File "/usr/local/lib/python3.9/site-packages/alembic/script/base.py", line 569, in run_env
    util.load_python_file(self.dir, "env.py")
  File "/usr/local/lib/python3.9/site-packages/alembic/util/pyfiles.py", line 94, in load_python_file
    module = load_module_py(module_id, path)
  File "/usr/local/lib/python3.9/site-packages/alembic/util/pyfiles.py", line 110, in load_module_py
    spec.loader.exec_module(module)  # type: ignore
  File "<frozen importlib._bootstrap_external>", line 850, in exec_module
  File "<frozen importlib._bootstrap>", line 228, in _call_with_frames_removed
  File "alembic/env.py", line 22, in <module>
    from src.core.config import settings
  File "/app/src/core/config.py", line 72, in <module>
    settings = Settings()
  File "pydantic/env_settings.py", line 40, in pydantic.env_settings.BaseSettings.__init__
  File "pydantic/env_settings.py", line 75, in pydantic.env_settings.BaseSettings._build_values
  File "pydantic/env_settings.py", line 200, in pydantic.env_settings.EnvSettingsSource.__call__
pydantic.env_settings.SettingsError: error parsing env var "BACKEND_CORS_ORIGINS"
Alembic migration done
[2022-11-15 21:25:36 +0000] [1] [INFO] Starting gunicorn 20.1.0
[2022-11-15 21:25:36 +0000] [1] [INFO] Listening at: http://0.0.0.0:8001 (1)
[2022-11-15 21:25:36 +0000] [1] [INFO] Using worker: uvicorn.workers.UvicornWorker
[2022-11-15 21:25:36 +0000] [23] [INFO] Booting worker with pid: 23
[2022-11-15 21:25:37 +0000] [24] [INFO] Booting worker with pid: 24
[2022-11-15 21:25:37 +0000] [25] [INFO] Booting worker with pid: 25
[2022-11-15 21:25:40 +0000] [23] [ERROR] Exception in worker process

现在它是如何设置的。

我的 docker-compose 文件使用 Dockerfile 构建。Dockerfile 的结尾如下。 CMD指令前有一个ENTRYPOINT

ENTRYPOINT ["./docker-entrypoint.sh"]
CMD ["./run.sh"]

docker-entrypoint.sh

if [ -n "$DB_SERVER" ]; then
  ./wait-for-it.sh "$DB_SERVER:${DB_PORT:-3306}"
fi

# Run the main container command.
exec "$@"

这是有效的，因为我可以从“等待”脚本中看到日志

run.sh （错误来自哪里）

export APP_MODULE=${APP_MODULE-src.main:app}
export HOST=${HOST:-0.0.0.0}
export PORT=${PORT:-8001}
export BACKEND_CORS_ORIGINS=${BACKEND_CORS_ORIGINS:-'http://localhost:8001'}

echo "Running migration with alembic"
# Run migrations
alembic upgrade head
echo "Alembic migration done"

exec gunicorn -b $HOST:$PORT "$APP_MODULE" --reload --workers=3 --timeout 0 -k uvicorn.workers.UvicornWorker

我已将默认值设置为 BACKEND_CORS_ORIGINS 以防万一。

在上面的堆栈跟踪中，您可以在第 2 行看到一个日志。 这是在 BACKEND_CORS_ORIGINS 的 pydantic 验证器中。 这是我的config.py文件的一部分：

class Settings(BaseSettings):
  BACKEND_CORS_ORIGINS: List[AnyHttpUrl] = ["http://localhost:3000", "http://localhost:8001"]

  @validator("BACKEND_CORS_ORIGINS", pre=True, allow_reuse=True)
      def assemble_cors_origins(cls, value: Union[str, List[str]]) -> Union[List[str], str]:
          logger.info(f"value for BACKEND_CORS_ORIGINS= {value}, type of BACKEND_CORS_ORIGINS= {type(value)}")
          backend_cors_origins = None
          if isinstance(value, str) and not value.startswith("["):
              backend_cors_origins = [i.strip() for i in value.split(",")]
          elif isinstance(value, (list, str)):
              backend_cors_origins = value
          logger.info(f"value for BACKEND_CORS_ORIGINS= {backend_cors_origins}, type of BACKEND_CORS_ORIGINS= {type(backend_cors_origins)}")
          if backend_cors_origins:
              return backend_cors_origins
          raise ValueError(value)

由于某些原因，我没有在日志的最后一部分看到我想要查看类型的地方。

最后，这是我的 Kube.netes 的Deployment.yml文件

apiVersion: apps/v1
kind: Deployment
metadata:
  namespace: dev
  name: api-name
spec:
  replicas: 1
  selector:
    matchLabels:
      app: api-name
  template:
    metadata:
      labels:
        app: api-name
    spec:
      imagePullSecrets:
        - name: secret_name
      containers:
      - name: api-name
        image: [private_registry]/api
        env:
        - name: MARIADB_USER
          value: 'db_user'
        - name: MARIADB_PASSWORD
          value: 'password'
        - name: MARIADB_SERVER
          value: 'IP_DB_SERVER'
        - name: MARIADB_DATABASE
          value: 'db_name'
        - name: MARIADB_PORT
          value: '1234'
        - name: BACKEND_CORS_ORIGINS
          value: 'http://localhost:8001'
        resources:
          limits:
            memory: "512Mi"
            cpu: "500m"
        ports:
        - containerPort: 8001
---
apiVersion: v1
kind: Service
metadata:
  namespace: dev
  name: svc-api
spec:
  type: NodePort
  selector:
    app: api-name
  ports:
  - port: 8001
    targetPort: 8001

有人可以帮助或指出我正确的方向吗？ 一直在尝试我所知道的一切来解决这个问题，但没有任何运气。

也许我需要更多 Kube.netes 的配置文件？

如果我删除run.sh脚本中的 alembic 命令，我仍然会收到相同的错误，但 @validator 中没有日志

Answer 1

这个问题似乎来自这条出口线

BACKEND_CORS_ORIGINS=${BACKEND_CORS_ORIGINS:-'http://localhost:8001'} 

似乎需要一个 URL 列表，所以也许你可以更改代码

 - name: BACKEND_CORS_ORIGINS 
   value: 
     - 'localhost:8001' 

在 Deployment.yml