我有一個 docker compose 文件,如下所示:
version: "3.9" services: mysqldb: image: mysql:5.7 container_name: mysqlcontainer command: --default-authentication-plugin=mysql_native_password volumes: - ./db/init.sql:/docker-entrypoint-initdb.d/0_init.sql ports: - 3306:3306 expose: - 3306 environment: MYSQL_DATABASE: "todos" MYSQL_USER: "admin" MYSQL_PASSWORD: "password" MYSQL_ROOT_PASSWORD: "password" SERVICE_TAGS: dev SERVICE_NAME: mysqldb restart: on-failure networks: - internalnet expressapp: container_name: api build: . image: expressapp:1.0 ports: - "3001:3001" expose: - "3001" environment: DB_HOST: mysqldb DB_PORT: 3306 DB_USER: "admin" DB_PASSWORD: "password" DB_NAME: todos DB_CONNECTION_LIMIT: 20 SERVICE_TAGS: dev SERVICE_NAME: expressapp PORT: 3001 depends_on: - mysqldb networks: - internalnet networks: internalnet: driver: bridge volumes: database:
如果我使用 docker compose up -d
命令啟動容器并使用 ps
命令檢查正在運行的容器,我將得到以下輸出:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 9f338b733a1c expressapp:1.0 "docker-entrypoint.s…" 2 minutes ago Up 2 minutes 0.0.0.0:3001->3001/tcp api edef8027dc0a mysql:5.7 "docker-entrypoint.s…" 2 minutes ago Up 2 minutes 0.0.0.0:3306->3306/tcp, 33060/tcp mysqlcontainer
但是當我嘗試向服務器發(fā)出 API
請求時,我收到以下錯誤消息:
"There was an error processing your request: connect ECONNREFUSED 172.24.0.2:3306"
為什么是因為我將 DB_HOST
變量設置為 mysql
服務名稱?
出現此問題的原因可能是 expressapp
在 mysql
可用于查詢之前啟動。
要控制服務啟動順序,您可以將 healthcheck
添加到 mysqldb
服務:
healthcheck: test: mysql ${MYSQL_DATABASE} --user=${MYSQL_USER} --password='${MYSQL_PASSWORD}' --silent --execute "SELECT 1;" interval: 30s timeout: 10s retries: 5
和 depends_on
塊到 expressapp
depends_on: mysqldb: condition: service_healthy
查看完整示例此處
有關此內容的更多信息,請參閱此答案。