infrapuzzle/k8s/n8n/garth-wrapper-script_config...

85 lines
3.7 KiB
YAML

# configmap.yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: garth-wrapper-script
namespace: n8n
data:
wrapper.py: |
# wrapper.py
import subprocess
import logging
from flask import Flask, request, Response
# Configure basic logging
logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')
# Initialize the Flask application
app = Flask(__name__)
# Define the main endpoint that n8n will call. It only accepts POST requests.
@app.route('/mcp', methods=['POST'])
def mcp_wrapper():
"""
This function receives a POST request from n8n, executes the garth-mcp-server
as a subprocess, pipes the request body to the subprocess's stdin,
captures its stdout, and returns it as the HTTP response.
"""
# Retrieve the raw binary data from the incoming request body.
request_data = request.get_data()
logging.info(f"Received request with {len(request_data)} bytes of data.")
# Define the command to execute the garth-mcp-server.
# 'uvx' is the recommended runner for this package.
command = ['uvx', 'garth-mcp-server']
try:
# Execute the command as a subprocess.
# - input: The data to be sent to the subprocess's stdin.
# - capture_output=True: Captures stdout and stderr.
# - check=True: Raises a CalledProcessError if the command returns a non-zero exit code.
# - timeout: Sets a 60-second timeout to prevent hanging processes.
result = subprocess.run(
command,
input=request_data,
capture_output=True,
check=True,
timeout=60
)
# If the command was successful, log the success and return the captured stdout.
# The content type is set to text/plain to ensure proper handling by clients.
logging.info(f"Subprocess executed successfully. Returning {len(result.stdout)} bytes of stdout.")
return Response(result.stdout, mimetype='text/plain', status=200)
except subprocess.CalledProcessError as e:
# If the subprocess returns a non-zero exit code, it indicates an error.
# Log the error, including the captured stderr for debugging.
error_message = e.stderr.decode('utf-8', errors='ignore')
logging.error(f"Subprocess failed with exit code {e.returncode}. Stderr: {error_message}")
return Response(f"Error executing garth-mcp-server: {error_message}", mimetype='text/plain', status=500)
except subprocess.TimeoutExpired:
# If the subprocess takes longer than the specified timeout.
logging.error("Subprocess timed out after 60 seconds.")
return Response("Error: garth-mcp-server process timed out.", mimetype='text/plain', status=504)
except Exception as e:
# Catch any other unexpected exceptions.
logging.error(f"An unexpected error occurred: {str(e)}")
return Response(f"An unexpected server error occurred: {str(e)}", mimetype='text/plain', status=500)
# Define a simple health check endpoint for Kubernetes liveness and readiness probes.
@app.route('/healthz', methods=['GET'])
def health_check():
"""
A simple endpoint that returns a 200 OK response, indicating the
Flask server is running and responsive.
"""
return Response("OK", status=200)
# Main execution block to run the Flask development server.
# host='0.0.0.0' makes the server accessible from outside the container.
# port=5000 is the port the server will listen on.
if __name__ == '__main__':
app.run(host='0.0.0.0', port=5000)