Docker Compose ve PostgreSQL

Giriş

Docker compose ile kullanmak için bazı notlar

Image İsmi

Şunlar olabilir

- postgres:11.1

- postgres:13.3

- postgres:15.1

- postgres:15rc2

- debezium/postgres

- debezium/postgres:13

En Basit

Şöyle yaparız

version: '3'
services:

  authorization-db:
    image: postgres:11.1
    container_name: auth-db
    ports:
      - "5432:5432"

command Alanı

Şunlar olabilir

- max_connections

- max_prepared_transactions

Örnek - max_ connections

Şöyle yaparız

services:
  database:
    image: postgres:latest
    command: postgres -c 'max_connections=250'

environment Alanı

Ortam Değişkenleri Şunlar olabilir

- POSTGRES_PASSWORD

- POSTGRES_USER

- POSTGRES_DB

Örnek

Şöyle yaparız. Burada iki tane veri tabanı çalıştırılıyor.

version: '3'
services:
  course-catalog-operational-db:
    image: postgres:13.3
    container_name: course-catalog-operational-db
    command:
      - "postgres"
      - "-c"
      - "wal_level=logical"
    environment:
      POSTGRES_PASSWORD: 123456
      POSTGRES_DB: course-catalog-db
    ports:
      - "5433:5432"
  instructors-legacy-db:
    image: postgres:13.3
    container_name: instructors-legacy-db
    command:
      - "postgres"
      - "-c"
      - "wal_level=logical"
    environment:
      POSTGRES_PASSWORD: 123456
      POSTGRES_DB: instructors-db
    ports:
      - "5434:5432"
    volumes:
      - ./init.sql:/docker-entrypoint-initdb.d/init.sql

Örnek - Hasura GraphQL + PostgreSQL 15

Şöyle yaparız

version: '3.6'
services:
  postgres:
    image: postgres:15rc2
    restart: always
    volumes:
    - db_data:/var/lib/postgresql/data
    environment:
      POSTGRES_PASSWORD: postgrespassword
    ports:
    - "5432:5432"
  graphql-engine:
    image: hasura/graphql-engine:v2.13.0
    ports:
    - "8080:8080"
    depends_on:
    - "postgres"
    restart: always
    environment:
      ## postgres database to store Hasura metadata
      HASURA_GRAPHQL_METADATA_DATABASE_URL: postgres://postgres:postgrespassword@postgres:5432/postgres
      ## this env var can be used to add the above postgres database to Hasura as a data source. this can be removed/updated based on your needs
      PG_DATABASE_URL: postgres://postgres:postgrespassword@postgres:5432/postgres
      ## enable the console served by server
      HASURA_GRAPHQL_ENABLE_CONSOLE: "true" # set to "false" to disable console
      ## enable debugging mode. It is recommended to disable this in production
      HASURA_GRAPHQL_DEV_MODE: "true"
      HASURA_GRAPHQL_ENABLED_LOG_TYPES: startup, http-log, webhook-log, websocket-log, query-log
      ## uncomment next line to set an admin secret
      HASURA_GRAPHQL_ADMIN_SECRET: myadminsecretkey
volumes:
  db_data:

docker-entrypoint-initdb

Veri tabanı başlarken çalıştırılacak SQL dosyalarını belirtiriz

Örnek

Şöyle yaparız

services:
  postgres:
    image: postgres
    ports:
      - "5432:5432"
    restart: always
    environment:
      POSTGRES_PASSWORD: password
      POSTGRES_DB: blogdb
      POSTGRES_USER: user
    volumes:
      - ./data/postgresql:/var/lib/postgresql
      - ./pg-initdb.d:/docker-entrypoint-initdb.d

healthcheck

Örnek

Şöyle yaparız. 

-q ile quite belirtiliyor

-d ile ile veri tabanı ismi belirtiliyor

-U ile kullanıcı ismi belirtiliyor

version: '3'services:
  postgres:
    image: postgres:13.1
    healthcheck:
      test: [ "CMD", "pg_isready", "-q", "-d", "postgres", "-U", "root" ]
      timeout: 45s
      interval: 10s
      retries: 10
    restart: always
    environment:
      - POSTGRES_USER=root
      - POSTGRES_PASSWORD=password
      - APP_DB_USER=docker
      - APP_DB_PASS=docker
      - APP_DB_NAME=docker
    volumes:
      - ./db:/docker-entrypoint-initdb.d/
    ports:
      - 5432:5432

Örnek

Şöyle yaparız. Kullanıcı ismi -U ile belirtiliyor

postgres:
  container_name: scheduling-airflow-postgres
  image: postgres:13
  environment:
    POSTGRES_USER: airflow
    POSTGRES_PASSWORD: airflow
    POSTGRES_DB: airflow
  deploy:
    resources:
      limits:
        cpus: "0.40"
        memory: 1200M
  volumes:
    - postgres-db-volume:/var/lib/postgresql/data
  healthcheck:
    test: ["CMD", "pg_isready", "-U", "airflow"]
    interval: 5s
    retries: 5
  restart: always
  profiles:
    - scheduling
  networks:
    - datastack  

restart Alanı

Genellikle always değeri verilir. Açıklaması şöyle

restart always : is used to restart the container if there is an error when creating the container.

volumes Alanı

Pod'un kullandığı /var/lib/postgresql/data dizini bir volume'a bağlanır

Örnek

Şöyle yaparız

version: '3.8'

services:
  ...
  db:
    image: postgres:15.2
    restart: always
    environment:
      POSTGRES_USER: book-user
      POSTGRES_PASSWORD: k9ZqLC
      POSTGRES_DB: bookdb
    volumes:
      - db-data:/var/lib/postgresql/data
    ports:
      - 6432:5432
volumes:
  db-data:
    driver: local