Use environment variable with Postgres initialization script run by docker-composer-CodePudding

I've created a database initialization script that creates the database and adds an entry to a specific table.

insert into user (email) values (${USER_EMAIL})

My docker-compose file is similar to this one:

version: '3.7'
services:
    postgres:
        image: postgres:10.5
        restart: always
        environment: 
          - POSTGRES_USER=postgres
          - POSTGRES_PASSWORD=postgres
        logging:
          options:
            max-size: 10m
            max-file: "3"
        ports:
          - '5438:5432'
        volumes:
          - ./postgres-data:/var/lib/postgresql/data
          # copy the sql script to create tables
          - ./sql/create_tables.sql:/docker-entrypoint-initdb.d/create_tables.sql
          # copy the sql script to fill tables
          - ./sql/fill_tables.sql:/docker-entrypoint-initdb.d/fill_tables.sql

USER_EMAIL is an env variable is is not being set in the script. What's the right way to do this?

CodePudding user response：

if you want to give a value for USER_EMAIL, you can simply add it in environment section.

version: '3.7'
services:
    postgres:
        image: postgres:10.5
        restart: always
        environment: 
          - POSTGRES_USER=postgres
          - POSTGRES_PASSWORD=postgres
          - USER_EMAIL
        logging:
          options:
            max-size: 10m
            max-file: "3"
        ports:
          - '5438:5432'
        volumes:
          - ./postgres-data:/var/lib/postgresql/data
          # copy the sql script to create tables
          - ./sql/create_tables.sql:/docker-entrypoint-initdb.d/create_tables.sql
          # copy the sql script to fill tables
          - ./sql/fill_tables.sql:/docker-entrypoint-initdb.d/fill_tables.sql

in your script just set a value for USER_EMAIL.

CodePudding user response：

The USER_EMAIL is not going to be available in sql file. I think you already tried that. Try using envsubst. So something like

command: >
  /bin/bash -c "envsubst < '$USER\_EMAIL' > ./initdb/fill_tables.sql"

I haven't tried pulling that pg image. So not sure if envsubst is available inside.