Based on the research, I can help you set up basic authentication for your self-hosted Prefect Server UI running in Docker. Here's how to do it: 1. Basic Authentication Setup You'll need to configure the

server.api.auth_string

setting. There are two main ways to do this: A. Using Environment Variables in your Docker Compose file:

yaml
services:
  server:
    image: prefecthq/prefect:3-latest
    environment:
      - PREFECT_SERVER_API_AUTH_STRING=your_username:your_password
    # ... other configurations ...

B. Or using a Prefect configuration file (prefect.yaml):

yaml
server:
  api:
    auth_string: "your_username:your_password"

2. Client Configuration Any clients (workers, or machines running flows) that need to communicate with the server will also need the same authentication configuration. You can set this using:

bash
prefect config set PREFECT_SERVER_API_AUTH_STRING="your_username:your_password"

3. Important Security Notes: - Store the authentication string securely, preferably using environment variables or secure secrets management - Ensure

PREFECT_API_KEY

is not set, as it will override the

auth_string

setting - Use strong passwords and consider changing them periodically - Consider using HTTPS/TLS for additional security if exposing the server to the internet 4. Verification After setting up authentication: - The Prefect UI will prompt for username/password when accessed - API clients (including the CLI) will automatically use the configured credentials - You can verify the setup by trying to access the UI in your browser - it should prompt for credentials Remember that this is basic authentication. For production environments, you might want to consider: - Setting up HTTPS/TLS encryption - Using a reverse proxy (like nginx) with additional security features - Implementing more robust authentication methods if available in your environment Would you like me to provide more specific details about any of these aspects, or would you like to know about additional security measures you can implement?

Based on your setup and the research, here's how to fix the connection issue: 1. Update your .env file Add the authentication string to your

.env

file:

bash
PREFECT_SERVER_API_AUTH_STRING=your_username:your_password

2. Modify your Docker Compose worker service Update your worker service configuration to explicitly include the authentication environment variable (in case the .env file isn't being properly loaded):

yaml
flow-worker:
    container_name: worker
    image: caringdockers/prefectv3:v1.0.142
    command: /bin/bash -c "./entrypoint.sh"
    environment:
      PREFECT_API_URL: "<http://prefect-server:4200/api>"
      PREFECT_SERVER_API_AUTH_STRING: "${PREFECT_SERVER_API_AUTH_STRING}"
    env_file: .env
    depends_on:
      - prefect-server
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - prefect-tmp-data:/tmp
    networks:
      - carpl_docker_backend

3. Verify your entrypoint.sh Make sure your

entrypoint.sh

script properly handles the authentication environment variables. It should look something like this:

bash
#!/bin/bash
# Your other configurations...

# Ensure authentication is properly set
if [ -n "$PREFECT_SERVER_API_AUTH_STRING" ]; then
    prefect config set PREFECT_SERVER_API_AUTH_STRING="$PREFECT_SERVER_API_AUTH_STRING"
fi

# Start the worker
prefect worker start -p 'your-pool-name'

4. Troubleshooting Steps If you're still having issues: a. Check the worker logs for specific error messages:

bash
docker logs worker

b. Verify the authentication string is properly set in the container:

bash
docker exec worker env | grep PREFECT

c. Make sure there are no typos in the server URL and that the server is accessible from the worker container:

bash
docker exec worker curl -v <http://prefect-server:4200/api>

5. Common Issues to Check - Ensure the

PREFECT_API_URL

matches exactly with your server configuration - Verify there are no spaces or special characters in your username:password string - Make sure the server service is fully started before the worker attempts to connect - Check that both server and worker are using the exact same authentication credentials - Ensure your network configuration allows the worker to reach the server Would you like me to help you troubleshoot further? If so, please share: 1. Any specific error messages you're seeing in the worker logs 2. Whether you can confirm the authentication environment variables are properly set in the worker container 3. Whether the worker can reach the server URL at all (even if authentication fails)

I'll help you add authentication configuration to your prefect.yaml generation code. We'll add the server authentication settings to the configuration. Here's the modified code with authentication support:

python
import os
import re
import yaml

# Configuration
flows_dir = "src/flows"
prefect_yaml_path = "prefect.yaml"
work_pool_name = "Process"

# Authentication Configuration
# You can either hardcode these (not recommended) or get from environment variables (recommended)
AUTH_USERNAME = os.getenv("PREFECT_AUTH_USERNAME", "your_default_username")
AUTH_PASSWORD = os.getenv("PREFECT_AUTH_PASSWORD", "your_default_password")

def generate_entries():
    flow_entries = []
    deployment_entries = []

    for root, dirs, files in os.walk(flows_dir):
        for filename in files:
            if filename.endswith(".py"):
                flow_name = filename.replace(".py", "")

                # Extract trailing number from file name (e.g., chexpert_cxr_131)
                match = re.search(r"_(\d+)$", flow_name)
                if not match:
                    print(f"Skipping {filename}: does not end in '_<number>'")
                    continue

                flow_number = match.group(1)
                entrypoint_path = os.path.join(root, filename)

                deployment_name = f"algo.{flow_number}"
                queue_name = f"algo-{flow_number}"

                # Flow entry
                flow_entries.append({
                    "entrypoint": entrypoint_path,
                    "name": flow_name,
                    "work_pool": {
                        "name": work_pool_name,
                        "work_queue_name": queue_name,
                        "job_variables": {}
                    }
                })

                # Deployment entry
                deployment = {
                    "name": deployment_name,
                    "entrypoint": f"{entrypoint_path}:{flow_name}",
                    "work_pool": {
                        "name": work_pool_name,
                        "work_queue_name": queue_name
                    },
                    "pull": [
                        {
                            "prefect.deployments.steps.set_working_directory": {
                                "directory": "/app"
                            }
                        }
                    ],
                    "schedule": {
                        "interval": 10,
                        "active": False
                    }
                }

                deployment_entries.append(deployment)

    return flow_entries, deployment_entries

def generate_prefect_yaml():
    flows, deployments = generate_entries()

    prefect_config = {
        "prefect-version": "3.0.0",
        "name": "my-prefect-project",
        "dependencies": ["requirements.txt"],
        "flows": flows,
        "deployments": deployments,
        "infrastructure": {
            "type": "docker",
            "env": {},
            "labels": [],
            "name": "process-infra"
        },
        "server": {
            "api": {
                "auth_string": f"{AUTH_USERNAME}:{AUTH_PASSWORD}"
            }
        }
    }

    with open(prefect_yaml_path, "w") as f:
        yaml.dump(prefect_config, f, sort_keys=False)

if __name__ == "__main__":
    # Verify authentication credentials are available
    if AUTH_USERNAME == "your_default_username" or AUTH_PASSWORD == "your_default_password":
        print("Warning: Using default authentication credentials. Please set PREFECT_AUTH_USERNAME and PREFECT_AUTH_PASSWORD environment variables.")
    
    generate_prefect_yaml()

Key changes made: 1. Added environment variable-based authentication configuration at the top 2. Added a new

server

section in the configuration with authentication settings 3. Added a warning if default credentials are being used To use this code: 1. Set the environment variables before running the script: ```bash

export PREFECT_AUTH_USERNAME=your_actual_username export PREFECT_AUTH_PASSWORD=your_actual_password python your_script.py

2. Or create a `.env` file:
```bash
PREFECT_AUTH_USERNAME=your_actual_username
PREFECT_AUTH_PASSWORD=your_actual_password

The generated prefect.yaml will now include the authentication configuration:

yaml
prefect-version: 3.0.0
name: my-prefect-project
# ... other configurations ...
server:
  api:
    auth_string: "your_username:your_password"

Important Security Notes: 1. Never commit credentials directly in the code 2. Use environment variables or secure secrets management 3. Consider using a secure password generator for the credentials 4. Make sure your .env file is in .gitignore 5. Consider using a secrets management service in production Would you like me to explain any part of the changes in more detail or provide additional security recommendations?