FIWARE MCP Server

from mcp.server.fastmcp import FastMCP import time import signal import sys import requests import json import logging # --- Logging to STDERR only --- logger = logging.getLogger("cb-assistant") logger.setLevel(logging.INFO) logger.handlers.clear() _stderr_handler = logging.StreamHandler(sys.stderr) _stderr_handler.setLevel(logging.INFO) logger.addHandler(_stderr_handler) logger.propagate = False # Handle SIGINT (Ctrl+C) gracefully def signal_handler(sig, frame): print("Shutting down server gracefully...") sys.exit(0) signal.signal(signal.SIGINT, signal_handler) # This MCP server provides tools for interacting with a FIWARE Context Broker mcp = FastMCP( name="CB-assistant", host="127.0.0.1", port=5001 ) # This tool gets the Context Broker version @mcp.tool() def CB_version(address: str="localhost", port: int=1026) -> str: """Return the version of the CB.""" try: url = f"http://{address}:{port}/version" response = requests.get(url) response.raise_for_status() # Raise an exception for bad status codes return json.dumps(response.json()) except requests.exceptions.RequestException as e: return json.dumps({"error": str(e)}) # This tool gets all entities from the Context Broker # - You can add extra headers to the request if needed # - Like adding a personalized context to the request # - The default headers are "Accept: application/json" and "Content-Type: application/json" # - This tool returns a JSON object with the entities and a count of the total number of entities in NGSILD-Results-Count @mcp.tool() def get_all_entities(address: str="localhost", port: int=1026, limit=1000, extra_headers: str="") -> str: """Get all entities from the Context Broker.""" try: url = f"http://{address}:{port}/ngsi-ld/v1/entities?limit={limit}" params = { "local": "true", "count": "true" } headers = { "Accept": "application/json" } # Add any extra headers if provided if extra_headers: try: extra_headers_dict = json.loads(extra_headers) headers.update(extra_headers_dict) except json.JSONDecodeError: return json.dumps({"error": "Invalid extra_headers format. Must be valid JSON string"}) response = requests.get(url, params=params, headers=headers) response.raise_for_status() return json.dumps(response.json()) except requests.exceptions.RequestException as e: return json.dumps({"error": str(e)}) # This tool gets all entity types from the Context Broker # - You can add extra headers to the request if needed # - Like adding a personalized context to the request # - The default headers are "Accept: application/json" @mcp.tool() def get_entity_types(address: str="localhost", port: int=1026, limit=1000, extra_headers: str="") -> str: """Get entity types from the Context Broker.""" try: url = f"http://{address}:{port}/ngsi-ld/v1/types?limit={limit}" headers = { "Accept": "application/json" } # Add any extra headers if provided if extra_headers: try: extra_headers_dict = json.loads(extra_headers) headers.update(extra_headers_dict) except json.JSONDecodeError: return json.dumps({"error": "Invalid extra_headers format. Must be valid JSON string"}) response = requests.get(url, headers=headers) response.raise_for_status() return json.dumps(response.json()) except requests.exceptions.RequestException as e: return json.dumps({"error": str(e)}) # This tool allows to execute any query to the Context Broker # - You should provide the full or partial URL of the query # - For example, to get the entity of type "Building" whose name is "Building 1" you should provide the following URL: # 'GET http://localhost:1026/ngsi-ld/v1/entities/Building/name/Building%201' or 'GET /ngsi-ld/v1/entities/Building/name/Building%201' # you need to provide the proper parameter for the GET request @mcp.tool() def execute_query(params: str) -> str: """ This tools just passes the query to the Context Broker and returns the response You should provide the full or partial VALID query to the Context Broker you need to provide the proper parameter for the GET request. For example, to get the entity of type "Building" whose name is "Building 1" you should provide the following URL: 'GET http://localhost:1026/ngsi-ld/v1/entities/Building/name/Building%201' or 'GET /ngsi-ld/v1/entities/Building/name/Building%201' """ base_url = "http://localhost:1026" # Normalize params without printing anything to stdout if isinstance(params, str) and params.strip().startswith("GET"): params = params.strip()[3:] if isinstance(params, str) and params.strip().startswith("http://localhost:1026/"): params = params.strip()[len("http://localhost:1026/"):] params = params.lstrip("/").replace(" ", "") # Check if params start with "/" (possibly with leading spaces), and strip spaces and the first slash if isinstance(params, str): params = params.lstrip() if params.startswith("/"): params = params[1:] full_url = f"{base_url}/{params}" headers = { "Accept": "application/ld+json, application/json;q=0.9, */*;q=0.1", "Link": '<http://context/user-context.jsonld>; rel="http://www.w3.org/ns/json-ld#context"; type="application/ld+json"', } try: logger.info("Requesting: %s", full_url) resp = requests.get(full_url, headers=headers) # Try JSON; fall back to text try: body = resp.json() except ValueError: body = {"raw_response": resp.text} # Return ONLY JSON to stdout result = { "status": resp.status_code, "headers": dict(resp.headers), "body": body, } # Raise for non-2xx after capturing body, but still return JSON error resp.raise_for_status() return json.dumps(result) except requests.exceptions.RequestException as e: # Still return valid JSON return json.dumps({"error": str(e), "url": full_url}) # This tool creates or updates entities in the Context Broker @mcp.tool() def publish_to_CB(address: str="localhost", port: int=1026, entity_data: dict=None) -> str: """Publish an entity to the CB.""" broker_url = f"http://{address}:{port}/ngsi-ld/v1/entities" # Default URL, adjust if needed headers = { "Content-Type": "application/ld+json" } try: response = requests.post(broker_url, json=entity_data, headers=headers) if response.status_code == 201: print(f"Success! Entity created. Status code: {response.status_code}") elif response.status_code == 409: print(f"Entity already exists. Status code: {response.status_code}") # Update the entity if it already exists entity_id = entity_data["id"] update_url = f"{broker_url}/{entity_id}/attrs" # Remove id, type and context for update update_data = entity_data.copy() update_data.pop("id", None) update_data.pop("type", None) update_data.pop("@context", None) update_response = requests.patch(update_url, json=update_data, headers=headers) print(f"Update attempt result: {update_response.status_code}") else: print(f"Error creating entity. Status code: {response.status_code}") print(f"Response content: {response.text}") except Exception as e: print(f"An error occurred: {e}") print("\nEntity data sent:") print(json.dumps(entity_data, indent=2)) return json.dumps({"status": "completed"}) if __name__ == "__main__": try: print("Starting MCP server 'CB-assistant' on 127.0.0.1:5001") # Use this approach to keep the server running mcp.run() except Exception as e: print(f"Error: {e}") # Sleep before exiting to give time for error logs time.sleep(3)