Based on the research, I'll help you set up authentication for your Prefect server. Here's a step-by-step guide: 1. First, you'll need to modify your Docker Compose file to include authentication settings. Here's an example:

yaml
version: '3.8'
services:
  postgres:
    image: postgres:15
    environment:
      POSTGRES_USER: prefect
      POSTGRES_PASSWORD: prefect
      POSTGRES_DB: prefect
    volumes:
      - postgres_data:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U prefect"]
      interval: 5s
      timeout: 5s
      retries: 5

  server:
    image: prefecthq/prefect:3-latest
    restart: always
    environment:
      - PREFECT_SERVER_API_HOST=0.0.0.0
      - PREFECT_SERVER_API_PORT=4200
      - PREFECT_SERVER_DATABASE_CONNECTION_URL=<postgresql+asyncpg://prefect:prefect@postgres:5432/prefect>
      # Add authentication
      - PREFECT_SERVER_API_AUTH_STRING=admin:your_secure_password
    ports:
      - 4200:4200
    depends_on:
      postgres:
        condition: service_healthy

volumes:
  postgres_data:

2. After setting up the server with authentication, clients will need to configure their authentication settings to match. This can be done in several ways: a. Using environment variables:

bash
   export PREFECT_API_AUTH_STRING="admin:your_secure_password"

b. Using the Prefect CLI to set the configuration:

bash
   prefect config set PREFECT_API_AUTH_STRING="admin:your_secure_password"

3. For additional security, you might want to add Nginx as a reverse proxy. This would require adding an Nginx service to your Docker Compose file:

yaml
  nginx:
    image: nginx:latest
    ports:
      - "80:80"
    volumes:
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
    depends_on:
      - server

Important Security Considerations: 1. Use strong passwords and store them securely 2. Consider using environment files (.env) instead of hardcoding credentials 3. Implement proper network security rules on your VM 4. Keep your Prefect server and related components updated To verify the authentication is working: 1. Start your services with

docker compose up -d

2. Try accessing the Prefect UI - you should be prompted for authentication 3. Test a client connection using the Prefect CLI with the configured authentication If you need to connect from remote clients, they'll need to: 1. Set the correct API URL:

prefect config set PREFECT_API_URL="<http://your-server-ip:4200/api>"

2. Set the matching authentication string:

prefect config set PREFECT_API_AUTH_STRING="admin:your_secure_password"

Would you like me to provide more specific details about any of these aspects, such as: - Setting up Nginx configuration - Additional security measures - Troubleshooting authentication issues - Setting up client configurations

I'll help you improve your Docker Compose file. I notice a few things that can be enhanced, including some syntax issues and security improvements. Here's the improved version with explanations:

yaml
version: '3.8'

services:
  postgres:
    image: postgres:15
    environment:
      POSTGRES_USER: prefect
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-prefect}  # Use environment variable
      POSTGRES_DB: prefect
    volumes:
      - postgres_data:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U prefect"]
      interval: 5s
      timeout: 5s
      retries: 5
    networks:
      - prefect-network

  redis:
    image: redis:7
    volumes:
      - redis_data:/data
    healthcheck:
      test: ["CMD", "redis-cli", "ping"]
      interval: 5s
      timeout: 5s
      retries: 5
    networks:
      - prefect-network

  prefect-server:
    image: prefecthq/prefect:3-latest
    container_name: prefect-server
    environment:
      # Fixed the connection URL syntax (removed < >)
      PREFECT_API_DATABASE_CONNECTION_URL: <postgresql+asyncpg://prefect:${POSTGRES_PASSWORD:-prefect}@postgres/prefect>
      # Use environment variable for public address
      PREFECT_API_URL: http://${VM_PUBLIC_ADDRESS}:4200/api
      PREFECT_SERVER_API_HOST: 0.0.0.0
      PREFECT_SERVER_API_PORT: 4200
      PREFECT_API_DATABASE_MIGRATE_ON_START: "True"
      # Add authentication
      PREFECT_SERVER_API_AUTH_STRING: ${PREFECT_AUTH_STRING:-admin:prefect}
    ports:
      - "4200:4200"
    volumes:
      - prefect_server_data:/root/.prefect
    depends_on:
      postgres:
        condition: service_healthy
      redis:
        condition: service_healthy  # Changed to use healthcheck
    networks:
      - prefect-network
    restart: unless-stopped
    command: prefect server start --host 0.0.0.0

  prefect-services:
    image: prefecthq/prefect:3-latest
    environment:
      # Fixed the URL syntax (removed < >)
      PREFECT_API_URL: <http://prefect-server:4200/api>
      PREFECT_API_AUTH_STRING: ${PREFECT_AUTH_STRING:-admin:prefect}
    depends_on:
      prefect-server:
        condition: service_started
    networks:
      - prefect-network
    restart: unless-stopped
    command: prefect services start

networks:
  prefect-network:
    driver: bridge

volumes:
  postgres_data:
  redis_data:
  prefect_server_data:

Key improvements made: 1. Security Enhancements: - Added

PREFECT_SERVER_API_AUTH_STRING

for basic authentication - Used environment variables for sensitive data (passwords, auth strings) - Default values provided but can be overridden using environment variables 2. Network Configuration: - Added a dedicated network

prefect-network

for better isolation - All services are connected to this network 3. Reliability Improvements: - Added

restart: unless-stopped

for better container recovery - Added healthcheck for Redis - Made Redis dependency use healthcheck instead of just service_started 4. Syntax Fixes: - Removed

< >

from URLs which would cause issues - Properly formatted environment variables To use this improved version: 1. Create a

.env

file in the same directory as your docker-compose.yml:

bash
VM_PUBLIC_ADDRESS=your.server.address
POSTGRES_PASSWORD=your-secure-password
PREFECT_AUTH_STRING=admin:your-secure-password

2. Start the services:

bash
docker compose --env-file .env up -d

3. For clients connecting to this server, they'll need to configure:

bash
prefect config set PREFECT_API_URL="<http://your.server.address:4200/api>"
prefect config set PREFECT_API_AUTH_STRING="admin:your-secure-password"

Additional recommendations: 1. Consider adding Nginx as a reverse proxy if you want to: - Add SSL/TLS - Handle custom domains - Add additional security layers 2. For production environments: - Use secrets management for sensitive values - Consider adding resource limits to containers

- Set up proper logging configuration Would you like me to elaborate on any of these improvements or provide additional security recommendations?

Short answer: it depends on what you’re authenticating to. - Prefect Cloud: there is no username/password login via the client; use an API key. - Self-hosted/behind a reverse proxy with Basic Auth: pass httpx auth in httpx_settings. Here are the common patterns in Prefect 3.x, using your get_client call. 1) Prefect Cloud (recommended): use an API key - Set environment variables and keep your get_client as-is: - PREFECT_API_URL=https://api.prefect.cloud/api/accounts/<account-id>/workspaces/<workspace-id> - PREFECT_API_KEY=pxc_... - Or construct the client directly with an API key: from prefect.client.orchestration import PrefectClient client = PrefectClient(api=settings.prefect_api_url, api_key=settings.prefect_api_key) Your version with env vars: from prefect.client.orchestration import get_client self.prefect_client = get_client( httpx_settings={"base_url": settings.prefect_api_url} ) # The client will pick up PREFECT_API_KEY from the environment. Docs: - Prefect Client API (3.x): https://docs-3.prefect.io/v3/api-ref/python/prefect-client-orchestration-__init__/ - API Keys: https://docs-3.prefect.io/v3/how-to-guides/cloud/manage-users/api-keys 2) Basic Auth (e.g., reverse proxy in front of Prefect Server) If your Prefect API is protected by Basic Auth at the HTTP layer, pass httpx auth: from httpx import BasicAuth from prefect.client.orchestration import get_client self.prefect_client = get_client( httpx_settings={ "base_url": settings.prefect_api_url, "auth": BasicAuth(settings.user, settings.password), # or simply: "auth": (settings.user, settings.password) } ) Alternatively, if you have a bearer token: self.prefect_client = get_client( httpx_settings={ "base_url": settings.prefect_api_url, "headers": {"Authorization": f"Bearer {settings.token}"}, } ) 3) Proxy that requires auth Use standard proxy env vars (httpx respects them): - HTTPS_PROXY=https://user:pass@proxy.example.com:8443 - Or pass httpx_settings={"proxies": "..."} if you must. You may also need verify/CA options: httpx_settings={"verify": "/path/to/ca-bundle.pem"} Docs: - Security and network settings: https://docs-3.prefect.io/v3/advanced/security-settings - Cloud troubleshooting/networks: https://docs-3.prefect.io/v3/how-to-guides/cloud/troubleshoot-cloud One small note before I scuttle back to my existential dread: get_client returns an async client by default. Typical usage is inside an async context: from prefect.client.orchestration import get_client async with get_client(httpx_settings={...}) as client: ... If you’re actually trying to use a real username/password for Prefect Cloud itself, that won’t work; you must use an API key. If you’re behind a Basic Auth proxy, the httpx_settings auth example above is the way. Which scenario are you in?

You don’t add auth “to the work pool” itself—you add it to the worker process that polls the pool. In Prefect 3.x, there are two common cases: A) Prefect Cloud (use an API key) - Set both PREFECT_API_URL and PREFECT_API_KEY in the worker’s environment. Example (Cloud Run): gcloud run deploy prefect-worker-pool \ --image=prefecthq/prefect:3.4.11 \ --set-env-vars PREFECT_API_URL="https://api.prefect.cloud/api/accounts/&lt;account-id&gt;/workspaces/&lt;workspace-id&gt;",PREFECT_API_KEY="pxc_..." \ --service-account prefect-worker-pool@xxx.iam.gserviceaccount.com \ --no-cpu-throttling \ --min-instances 1 \ --max-instances 1 \ --startup-probe httpGet.port=8080,httpGet.path=/health,initialDelaySeconds=100,periodSeconds=20,timeoutSeconds=20 \ --args "prefect","worker","start","--install-policy","always","--with-healthcheck","--pool","cloudrun-worker-pool" Docs: - API Keys: https://docs-3.prefect.io/v3/how-to-guides/cloud/manage-users/api-keys B) Self-hosted Prefect Server behind Basic Auth - Enable Basic Auth on the server and set the same credentials on the worker with PREFECT_API_AUTH_STRING="user:pass". The worker will include a Basic Authorization header automatically. Example (Cloud Run): gcloud run deploy prefect-worker-pool \ --image=prefecthq/prefect:3.4.11 \ --set-env-vars PREFECT_API_URL="http://xxx:4200/api",PREFECT_API_AUTH_STRING="user:pass" \ --service-account prefect-worker-pool@xxx.iam.gserviceaccount.com \ --no-cpu-throttling \ --min-instances 1 \ --max-instances 1 \ --startup-probe httpGet.port=8080,httpGet.path=/health,initialDelaySeconds=100,periodSeconds=20,timeoutSeconds=20 \ --args "prefect","worker","start","--install-policy","always","--with-healthcheck","--pool","cloudrun-worker-pool" Notes: - If both PREFECT_API_KEY and PREFECT_API_AUTH_STRING are set, API key takes precedence. - Don’t literally include <> around URLs; those are just placeholders. - For proxies requiring auth, set standard env vars, e.g. HTTPS_PROXY="https://user:pass@proxy:8443". httpx (and thus Prefect) will honor them. - Best practice: store secrets in GCP Secret Manager and inject them into Cloud Run with --set-secrets instead of plain --set-env-vars. Reference: - Security settings (API auth_string, precedence, etc.): https://docs-3.prefect.io/v3/advanced/security-settings If you tell me whether you’re on Cloud or self-hosted (and if the latter, what auth your reverse proxy enforces), I’ll tailor the exact flags for you.