Mongodb Docker 内部的 Mongo 身份验证

我正在try 使用身份验证运行mongo docker映像.按照documentation中最简单的示例，我使用docker-compose up命令运行了mongo和mongo express图像.现阶段我的建议是:

version: '3.1'

services:

  mongo:
    image: mongo
    restart: always
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: example

  mongo-express:
    image: mongo-express
    restart: always
    ports:
      - 8081:8081
    environment:
      ME_CONFIG_MONGODB_ADMINUSERNAME: root
      ME_CONFIG_MONGODB_ADMINPASSWORD: example

运行时，两个容器都可以启动，我可以从mongo express网站浏览mongo的内容.但是，每当我更改docker-compose.yml文件中的用户名或密码时，例如:

version: '3.1'

services:

  mongo:
    image: mongo
    restart: always
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: example123

  mongo-express:
    image: mongo-express
    restart: always
    ports:
      - 8081:8081
    environment:
      ME_CONFIG_MONGODB_ADMINUSERNAME: root
      ME_CONFIG_MONGODB_ADMINPASSWORD: example123

mongo express会抛出未经分析的错误消息:

mongo-express_1  | Admin Database connected
mongo-express_1  | { MongoError: Authentication failed.
mongo-express_1  |     at Function.MongoError.create (/node_modules/mongodb-core/lib/error.js:31:11)
mongo-express_1  |     at /node_modules/mongodb-core/lib/connection/pool.js:483:72
mongo-express_1  |     at authenticateStragglers (/node_modules/mongodb-core/lib/connection/pool.js:429:16)
mongo-express_1  |     at Connection.messageHandler (/node_modules/mongodb-core/lib/connection/pool.js:463:5)
mongo-express_1  |     at Socket.<anonymous> (/node_modules/mongodb-core/lib/connection/connection.js:319:22)
mongo-express_1  |     at emitOne (events.js:116:13)
mongo-express_1  |     at Socket.emit (events.js:211:7)
mongo-express_1  |     at addChunk (_stream_readable.js:263:12)
mongo-express_1  |     at readableAddChunk (_stream_readable.js:250:11)
mongo-express_1  |     at Socket.Readable.push (_stream_readable.js:208:10)
mongo-express_1  |   name: 'MongoError',
mongo-express_1  |   message: 'Authentication failed.',
mongo-express_1  |   ok: 0,
mongo-express_1  |   errmsg: 'Authentication failed.',
mongo-express_1  |   code: 18,
mongo-express_1  |   codeName: 'AuthenticationFailed' }
mongo-express_1  | unable to list databases
mongo-express_1  | { MongoError: command listDatabases requires authentication
mongo-express_1  |     at Function.MongoError.create (/node_modules/mongodb-core/lib/error.js:31:11)
mongo-express_1  |     at /node_modules/mongodb-core/lib/connection/pool.js:483:72
mongo-express_1  |     at authenticateStragglers (/node_modules/mongodb-core/lib/connection/pool.js:429:16)
mongo-express_1  |     at Connection.messageHandler (/node_modules/mongodb-core/lib/connection/pool.js:463:5)
mongo-express_1  |     at Socket.<anonymous> (/node_modules/mongodb-core/lib/connection/connection.js:319:22)
mongo-express_1  |     at emitOne (events.js:116:13)
mongo-express_1  |     at Socket.emit (events.js:211:7)
mongo-express_1  |     at addChunk (_stream_readable.js:263:12)
mongo-express_1  |     at readableAddChunk (_stream_readable.js:250:11)
mongo-express_1  |     at Socket.Readable.push (_stream_readable.js:208:10)
mongo-express_1  |   name: 'MongoError',
mongo-express_1  |   message: 'command listDatabases requires authentication',
mongo-express_1  |   ok: 0,
mongo-express_1  |   errmsg: 'command listDatabases requires authentication',
mongo-express_1  |   code: 13,
mongo-express_1  |   codeName: 'Unauthorized' }

无论我在docker-compose.yml中输入什么用户名或密码，我都无法让mongo express连接到mongo，除非我使用原来的root和example对.

请注意，我没有将用户名和密码作为环境变量，但它们直接输入到docker-compose.yml文件中，如您所见.

还要注意的是，当我将MONGO_INITDB_ROOT_USERNAME和MONGO_INITDB_ROOT_PASSWORD(mongo’s)变量更改为任何值时，它们似乎都没有效果，我仍然可以使用原始根和示例凭据连接mongo express.

是什么导致了这种行为？我怎样才能做到这一点？