Prefect Test Env

Prefect Setup

Prefect Server Docker Deployment

name: prefect

services:
  prefect:
    image: rsubr/quark:25.05
    container_name: prefect.localhost
    restart: always
		
    command: "prefect server start"
		
    ports:
      - 4200:4200
			
    environment:
      - PREFECT_SERVER_API_HOST=0.0.0.0
      - PREFECT_SERVER_API_AUTH_STRING=admin:password
			
      - PREFECT_API_URL=http://localhost:4200/api
      - PREFECT_API_AUTH_STRING=admin:password
			
      - PREFECT_SERVER_DATABASE_CONNECTION_URL=postgresql+asyncpg://prefect:prefect@localhost:5432/prefect

Work Pools

Create work pools in the UI: http://localhost:4200/

Prefect Worker Deployment

name: prefect-worker

services:
  prefect-worker:
    image: rsubr/quark:25.05
    container_name: prefect-worker.localhost
    restart: always
		
    environment:
      - PREFECT_API_URL=http://localhost:4200/api
      - PREFECT_API_AUTH_STRING=admin:password
			
    # Set concurrency limit "-l" to 4 workers
    # Attach to work pool "test"
    command: prefect worker start --with-healthcheck -t process -l 4 -n "worker-1" -p "test"
		
    volumes:
      - /app:/app

Create Deployment in Prefect

1. Add the following Prefect environment variables to the local machine:

    prefect config set PREFECT_API_URL=http://localhost:4200/api
    prefect config set PREFECT_API_AUTH_STRING=admin:password
   

2. Python code example (/app/prefect-code/sample.py):

    from prefect import flow
   
    @flow(
        name="Test",
        log_prints=True,
    )
    def sample():
        print("Hello World!")
   

3. Create a deployment for this Python code:

   • Run the following command from the /app directory:

     prefect deploy
     

   • Choose the flow “Test” from the list.
   • Enter a deployment name.
   • No schedules needed.
   • Select the work pool from the list.
   • No need to pull code from a remote location.