Docker psycopg2.OperationalError: could not connect to server: Connection refused

Question

I am getting following error from docker below. Docker compose also below. I 've creste nw connection in admin connections with credentials same as in docker file means:

login: airflow
pass:  airflow
port:  5432
host:  localhost

How to fix that issue?

Error:

psycopg2.OperationalError: could not connect to server: Connection refused
    Is the server running on host "localhost" (127.0.0.1) and accepting
    TCP/IP connections on port 5432?
could not connect to server: Cannot assign requested address
    Is the server running on host "localhost" (::1) and accepting
    TCP/IP connections on port 5432?

Docker compose:

version: '3'

    x-airflow-common:
      &airflow-common
      image: ${AIRFLOW_IMAGE_NAME:-apache/airflow:2.1.0}
      environment:
        &airflow-common-env
        AIRFLOW__CORE__EXECUTOR: CeleryExecutor
        AIRFLOW__CORE__SQL_ALCHEMY_CONN: postgresql+psycopg2://airflow:airflow@postgres/airflow
        AIRFLOW__CELERY__RESULT_BACKEND: db+postgresql://airflow:airflow@postgres/airflow
        AIRFLOW__CELERY__BROKER_URL: redis://:@redis:6379/0
        AIRFLOW__CORE__FERNET_KEY: ''
        AIRFLOW__CORE__DAGS_ARE_PAUSED_AT_CREATION: 'true'
        AIRFLOW__CORE__LOAD_EXAMPLES: 'true'
        AIRFLOW__API__AUTH_BACKEND: 'airflow.api.auth.backend.basic_auth'
      volumes:
        - ./dags:/opt/airflow/dags
        - ./logs:/opt/airflow/logs
        - ./plugins:/opt/airflow/plugins
      user: "${AIRFLOW_UID:-50000}:${AIRFLOW_GID:-50000}"
      depends_on:
        redis:
          condition: service_healthy
        postgres:
          condition: service_healthy
    
    services:
      postgres:
        image: postgres:13
        environment:
          POSTGRES_HOST: localhost
          POSTGRES_USER: airflow
          POSTGRES_PASSWORD: airflow
          POSTGRES_DB: airflow
        ports:
          - "5432:5432"
        volumes:
          - postgres-db-volume:/var/lib/postgresql/data
        healthcheck:
          test: ["CMD", "pg_isready", "-U", "airflow"]
          interval: 5s
          retries: 5
        restart: always
    
      redis:
        image: redis:latest
        ports:
          - 6379:6379
        healthcheck:
          test: ["CMD", "redis-cli", "ping"]
          interval: 5s
          timeout: 30s
          retries: 50
        restart: always
    
      airflow-webserver:
        <<: *airflow-common
        command: webserver
        ports:
          - 8080:8080
        healthcheck:
          test: ["CMD", "curl", "--fail", "http://localhost:8080/health"]
          interval: 10s
          timeout: 10s
          retries: 5
        restart: always
    
      airflow-scheduler:
        <<: *airflow-common
        command: scheduler
        healthcheck:
          test: ["CMD-SHELL", 'airflow jobs check --job-type SchedulerJob --hostname "$${HOSTNAME}"']
          interval: 10s
          timeout: 10s
          retries: 5
        restart: always
    
      airflow-worker:
        <<: *airflow-common
        command: celery worker
        healthcheck:
          test:
            - "CMD-SHELL"
            - 'celery --app airflow.executors.celery_executor.app inspect ping -d "celery@$${HOSTNAME}"'
          interval: 10s
          timeout: 10s
          retries: 5
        restart: always
    
      airflow-init:
        <<: *airflow-common
        command: version
        environment:
          <<: *airflow-common-env
          _AIRFLOW_DB_UPGRADE: 'true'
          _AIRFLOW_WWW_USER_CREATE: 'true'
          _AIRFLOW_WWW_USER_USERNAME: ${_AIRFLOW_WWW_USER_USERNAME:-airflow}
          _AIRFLOW_WWW_USER_PASSWORD: ${_AIRFLOW_WWW_USER_PASSWORD:-airflow}
    
      flower:
        <<: *airflow-common
        command: celery flower
        ports:
          - 5555:5555
        healthcheck:
          test: ["CMD", "curl", "--fail", "http://localhost:5555/"]
          interval: 10s
          timeout: 10s
          retries: 5
        restart: always
    
    volumes:
      postgres-db-volume: