Introduction

When setting up Redash with Docker Compose, one of the common errors users might encounter is related to PostgreSQL authentication. Specifically, the psycopg2.OperationalError: fe_sendauth: no password supplied error can be frustrating, especially when you believe everything is configured correctly. This post will guide you through understanding and resolving this error.

Understanding the Error

The fe_sendauth: no password supplied error indicates that PostgreSQL is expecting a password for the connection, but none was provided. This can happen due to misconfigurations in your environment variables, Docker Compose file, or the way the create_db command is executed.

Common Setup

Typically, the Docker Compose setup for Redash might look something like this:

version: "2"
x-redash-service: &redash-service
  image: redash/redash:8.0.0.b32245
  depends_on:
    - postgres
    - redis
  env_file: /opt/redash/env
  restart: always

services:
  server:
    <<: *redash-service
    command: server
    ports:
      - "5000:5000"
    environment:
      REDASH_WEB_WORKERS: 4
  scheduler:
    <<: *redash-service
    command: scheduler
    environment:
      QUEUES: "celery"
      WORKERS_COUNT: 1
  scheduled_worker:
    <<: *redash-service
    command: worker
    environment:
      QUEUES: "scheduled_queries,schemas"
      WORKERS_COUNT: 1
  adhoc_worker:
    <<: *redash-service
    command: worker
    environment:
      QUEUES: "queries"
      WORKERS_COUNT: 2
  redis:
    image: redis:7-alpine
    restart: unless-stopped
  postgres:
    image: pgautoupgrade/pgautoupgrade:15-alpine3.8
    env_file: /opt/redash/env
    volumes:
      - /opt/redash/postgres-data:/var/lib/postgresql/data
    restart: unless-stopped
  nginx:
    image: redash/nginx:latest
    ports:
      - "80:80"
    depends_on:
      - server
    links:
      - server:redash
    restart: always

And the env file might look like this:

REDASH_HOST=http://localhost/redash
PYTHONUNBUFFERED=0
REDASH_LOG_LEVEL=INFO
REDASH_REDIS_URL=redis://redis:6379/0
POSTGRES_PASSWORD=postgres
REDASH_COOKIE_SECRET=redash-selfhosted
REDASH_SECRET_KEY=redash-selfhosted
REDASH_DATABASE_URL=postgresql://postgres@postgres/postgres

Encountering the Error

When you try to initialize the Redash database with the following command:

docker-compose run --rm server create_db

You might encounter the fe_sendauth: no password supplied error. This indicates that the POSTGRES_PASSWORD environment variable isn’t being correctly used by the create_db command.

Solution

To resolve this issue, you can pass the POSTGRES_PASSWORD directly when running the create_db command. Here’s how:

1. Remove the env_file Reference: Ensure that the env_file reference in your docker-compose.yml file for the server service is removed or overridden, so it doesn’t interfere.
2. Run the Command with Password: Use the -e option to explicitly pass the POSTGRES_PASSWORD as an environment variable:

docker-compose run --rm -e POSTGRES_PASSWORD=postgres server create_db

1. Replace postgres with the actual password if it’s different.

Conclusion

By passing the POSTGRES_PASSWORD directly in the docker-compose run command, you ensure that the correct password is used for PostgreSQL authentication. This method is effective in resolving the fe_sendauth: no password supplied error and allows you to proceed with setting up Redash successfully.