无法从api服务连接到docker容器中的db主机到db服务以便使用golang中的goose进行迁移

Question

goose is the migration tool that helps me to run all the *sql files and run up queries within database. I want to automate migrations(create tables and stuff) using this tool within the docker container on my api service. The problem is when docker runs command "goose run" it gets an error -goose run: dial tcp: lookup db on 192.168.63.6:53: no such host.

docker-compose

services:
  db:
    build: ./db
    volumes:
      - ./db/pgdata:/pgdata
    image: postgres
    ports:
      - "5432"
    restart: always
    environment:
      - POSTGRES_USER=user
      - POSTGRES_DB=dbname
      - POSTGRES_PASSWORD=123
      - PGDATA=/pgdata

  api:
    build:
      context: ./api
    restart: always
    volumes:
      - ./api:/go/src/github.com/gitlees/todoapp/api
    ports:
      - "5000:8080"
    links: 
      - "db"

Api Dockerfile

RUN go get -u github.com/pressly/goose/cmd/goose

RUN goose postgres "host=db user=user dbname=dbname sslmode=disable password=123" up

Answer 1

RUN commands are executed during build phase. During this phase there is no container yet.

Commands that are meant to connect to other containers should be defined in CMD or ENTRYPOINT in the Dockerfile.