Redash cannot connect to MySQL server through socket

Question

I want to connect redash to MySQL Server. I added MYSQL_TCP_PORT for server to use TCP connection, not default UNIX socket (to avoid mysqld.sock error). If I go to mysql container and mysql -p - I can open mysql shell. But If I test connection in redash - it will return (2006, "Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)").

Here is my docker-compose file:

# This configuration file is for the **development** setup.
# For a production example please refer to getredash/setup repository on GitHub.
version: "2.2"
x-redash-service: &redash-service
  build:
    context: .
    # args:
    #   skip_frontend_build: "true"  # set to empty string to build
  volumes:
    - .:/app
  env_file:
    - .env
x-redash-environment: &redash-environment
  REDASH_LOG_LEVEL: "INFO"
  REDASH_REDIS_URL: "redis://redis:6379/0"
  REDASH_DATABASE_URL: "postgresql://postgres@postgres/postgres"
  REDASH_RATELIMIT_ENABLED: "false"
  REDASH_MAIL_DEFAULT_SENDER: "redash@example.com"
  REDASH_MAIL_SERVER: "email"
  REDASH_ENFORCE_CSRF: "true"
  REDASH_GUNICORN_TIMEOUT: 60
  # Set secret keys in the .env file
services:
  server:
    <<: *redash-service
    command: dev_server
    depends_on:
      - postgres
      - redis
    ports:
      - "5000:5000"
      - "5678:5678"
    networks:
      - default_network
    environment:
      <<: *redash-environment
      PYTHONUNBUFFERED: 0
  scheduler:
    <<: *redash-service
    command: dev_scheduler
    depends_on:
      - server
    networks:
      - default_network
    environment:
      <<: *redash-environment
  worker:
    <<: *redash-service
    command: dev_worker
    depends_on:
      - server
    networks:
      - default_network
    environment:
      <<: *redash-environment
      PYTHONUNBUFFERED: 0
  redis:
    image: redis:3-alpine
    restart: unless-stopped
    networks:
      - default_network
  postgres:
    image: postgres:9.5-alpine
    # The following turns the DB into less durable, but gains significant performance improvements for the tests run (x3
    # improvement on my personal machine). We should consider moving this into a dedicated Docker Compose configuration for
    # tests.
    ports:
      - "15432:5432"
    command: "postgres -c fsync=off -c full_page_writes=off -c synchronous_commit=OFF"
    restart: unless-stopped
    networks:
      - default_network
    environment:
      POSTGRES_HOST_AUTH_METHOD: "trust"
  email:
    image: djfarrelly/maildev
    ports:
      - "1080:80"
    restart: unless-stopped
    networks:
      - default_network
  mysql:
    image: mysql/mysql-server:latest
    ports:
      - "3306:3306"
    restart: unless-stopped
    container_name: mysql
    networks:
      - default_network
    environment:
      MYSQL_ROOT_PASSWORD: "${MYSQL_ROOT_PASSWORD}"
      MYSQL_TCP_PORT: 3306

networks:
  default_network:
    external: false
    name: default_network
    driver: bridge

As I see - redash is connecting via unix socket - not TCP connection (otherwise there will no mysqld.sock err). I don't know - what I should fix in docker-compose or somewhere else to make it connect properly. Any suggestions? If you need me to provide more info - ask me please