feat: MCP server over SSE with OIDC auth
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- Extract shared MCP tool handlers to mcp_common.py
- mcp_server.py now uses shared handlers (stdio transport for local dev)
- New routes/mcp.py: SSE transport behind existing OIDC Bearer auth
- Mount MCP ASGI app at /mcp in main.py when AI_FEATURES_ENABLED
- /mcp/sse  -> establishes SSE stream (requires valid token when auth enabled)
- /mcp/messages/ -> receives MCP client messages
- Update README with SSE MCP docs
- Add tests for mount existence, auth, and message routing
This commit is contained in:
2026-04-21 07:38:12 +02:00
parent 6cf5c0a28b
commit 5122739c01
7 changed files with 370 additions and 213 deletions

View File

@@ -1,9 +1,9 @@
#!/usr/bin/env python3
"""
AOC MCP Server
AOC MCP Server — stdio transport
Standalone MCP server that exposes audit log search tools for Claude Desktop,
Cursor, and other MCP clients.
Standalone MCP server for local use (Claude Desktop, Cursor, etc.).
For the HTTP/SSE version (production, behind auth), see routes/mcp.py.
Usage:
python mcp_server.py
@@ -21,65 +21,28 @@ Claude Desktop config (~/.config/claude/claude_desktop_config.json):
"""
import asyncio
import json
import os
import sys
from datetime import UTC, datetime, timedelta
# Ensure backend modules are importable
# Ensure backend modules are importable when run standalone
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from database import events_collection
from mcp.server import Server
from mcp.server.stdio import stdio_server
from mcp.types import TextContent, Tool
from mcp_common import (
ASK_SCHEMA,
GET_EVENT_SCHEMA,
GET_SUMMARY_SCHEMA,
SEARCH_EVENTS_SCHEMA,
handle_ask,
handle_get_event,
handle_get_summary,
handle_search_events,
)
app = Server("aoc")
# ---------------------------------------------------------------------------
# Tool definitions
# ---------------------------------------------------------------------------
_SEARCH_EVENTS_SCHEMA = {
"type": "object",
"properties": {
"entity": {"type": "string", "description": "Device name, user UPN, or email to search for"},
"services": {
"type": "array",
"items": {"type": "string"},
"description": "Filter by service (e.g. Intune, Directory, Exchange)",
},
"operation": {"type": "string", "description": "Filter by operation name"},
"result": {"type": "string", "description": "Filter by result (success, failure)"},
"days": {"type": "integer", "description": "Number of days to look back (default 7)"},
"limit": {"type": "integer", "description": "Max events to return (default 20)"},
},
}
_GET_EVENT_SCHEMA = {
"type": "object",
"properties": {
"event_id": {"type": "string", "description": "The event ID to retrieve"},
},
"required": ["event_id"],
}
_GET_SUMMARY_SCHEMA = {
"type": "object",
"properties": {
"days": {"type": "integer", "description": "Number of days to summarise (default 7)"},
},
}
_ASK_SCHEMA = {
"type": "object",
"properties": {
"question": {"type": "string", "description": "Natural language question about audit logs"},
"days": {"type": "integer", "description": "Number of days to look back (default 7)"},
},
"required": ["question"],
}
@app.list_tools()
async def list_tools() -> list[Tool]:
@@ -87,186 +50,35 @@ async def list_tools() -> list[Tool]:
Tool(
name="search_events",
description="Search audit events by entity, service, operation, or result.",
inputSchema=_SEARCH_EVENTS_SCHEMA,
inputSchema=SEARCH_EVENTS_SCHEMA,
),
Tool(name="get_event", description="Retrieve a single audit event by its ID.", inputSchema=_GET_EVENT_SCHEMA),
Tool(name="get_event", description="Retrieve a single audit event by its ID.", inputSchema=GET_EVENT_SCHEMA),
Tool(
name="get_summary",
description="Get an aggregated summary of audit activity for the last N days.",
inputSchema=_GET_SUMMARY_SCHEMA,
inputSchema=GET_SUMMARY_SCHEMA,
),
Tool(
name="ask",
description="Ask a natural language question about audit logs. Returns a narrative answer.",
inputSchema=_ASK_SCHEMA,
inputSchema=ASK_SCHEMA,
),
]
# ---------------------------------------------------------------------------
# Tool handlers
# ---------------------------------------------------------------------------
@app.call_tool()
async def call_tool(name: str, arguments: dict) -> list[TextContent]:
if name == "search_events":
return await _handle_search_events(arguments)
return await handle_search_events(arguments)
if name == "get_event":
return await _handle_get_event(arguments)
return await handle_get_event(arguments)
if name == "get_summary":
return await _handle_get_summary(arguments)
return await handle_get_summary(arguments)
if name == "ask":
return await _handle_ask(arguments)
return await handle_ask(arguments)
raise ValueError(f"Unknown tool: {name}")
async def _handle_search_events(arguments: dict) -> list[TextContent]:
days = arguments.get("days", 7)
limit = min(arguments.get("limit", 20), 100)
since = (datetime.now(UTC) - timedelta(days=days)).isoformat().replace("+00:00", "Z")
filters = [{"timestamp": {"$gte": since}}]
services = arguments.get("services")
if services:
filters.append({"service": {"$in": services}})
operation = arguments.get("operation")
if operation:
filters.append({"operation": {"$regex": operation, "$options": "i"}})
result = arguments.get("result")
if result:
filters.append({"result": {"$regex": result, "$options": "i"}})
entity = arguments.get("entity")
if entity:
entity_safe = entity.replace(".", "\\.").replace("(", "\\(").replace(")", "\\)")
filters.append(
{
"$or": [
{"target_displays": {"$elemMatch": {"$regex": entity_safe, "$options": "i"}}},
{"actor_display": {"$regex": entity_safe, "$options": "i"}},
{"actor_upn": {"$regex": entity_safe, "$options": "i"}},
{"raw_text": {"$regex": entity_safe, "$options": "i"}},
]
}
)
query = {"$and": filters}
cursor = events_collection.find(query).sort("timestamp", -1).limit(limit)
events = list(cursor)
if not events:
return [TextContent(type="text", text="No matching events found.")]
lines = [f"Found {len(events)} event(s):\n"]
for e in events:
ts = e.get("timestamp", "?")[:16].replace("T", " ")
svc = e.get("service", "?")
op = e.get("operation", "?")
actor = e.get("actor_display", "?")
result_str = e.get("result", "?")
lines.append(f"{ts} | {svc} | {op} | {actor} | {result_str}")
return [TextContent(type="text", text="\n".join(lines))]
async def _handle_get_event(arguments: dict) -> list[TextContent]:
event_id = arguments["event_id"]
event = events_collection.find_one({"id": event_id})
if not event:
return [TextContent(type="text", text=f"Event {event_id} not found.")]
event.pop("_id", None)
return [TextContent(type="text", text=json.dumps(event, indent=2, default=str))]
async def _handle_get_summary(arguments: dict) -> list[TextContent]:
days = arguments.get("days", 7)
since = (datetime.now(UTC) - timedelta(days=days)).isoformat().replace("+00:00", "Z")
query = {"timestamp": {"$gte": since}}
total = events_collection.count_documents(query)
if total == 0:
return [TextContent(type="text", text="No events in the specified period.")]
# Aggregation pipelines
svc_pipeline = [
{"$match": query},
{"$group": {"_id": "$service", "count": {"$sum": 1}}},
{"$sort": {"count": -1}},
{"$limit": 10},
]
op_pipeline = [
{"$match": query},
{"$group": {"_id": "$operation", "count": {"$sum": 1}}},
{"$sort": {"count": -1}},
{"$limit": 10},
]
result_pipeline = [
{"$match": query},
{"$group": {"_id": "$result", "count": {"$sum": 1}}},
{"$sort": {"count": -1}},
]
actor_pipeline = [
{"$match": query},
{"$group": {"_id": "$actor_display", "count": {"$sum": 1}}},
{"$sort": {"count": -1}},
{"$limit": 10},
]
svc_counts = list(events_collection.aggregate(svc_pipeline))
op_counts = list(events_collection.aggregate(op_pipeline))
result_counts = list(events_collection.aggregate(result_pipeline))
actor_counts = list(events_collection.aggregate(actor_pipeline))
lines = [f"Summary for the last {days} days ({total} total events)\n"]
lines.append("By service:")
for row in svc_counts:
lines.append(f" {row['_id'] or 'Unknown'}: {row['count']}")
lines.append("\nBy action:")
for row in op_counts:
lines.append(f" {row['_id'] or 'Unknown'}: {row['count']}")
lines.append("\nBy result:")
for row in result_counts:
lines.append(f" {row['_id'] or 'Unknown'}: {row['count']}")
lines.append("\nTop actors:")
for row in actor_counts:
lines.append(f" {row['_id'] or 'Unknown'}: {row['count']}")
return [TextContent(type="text", text="\n".join(lines))]
async def _handle_ask(arguments: dict) -> list[TextContent]:
"""For now, the MCP 'ask' tool returns a helpful message directing the user to the web UI,
since the full NLQ pipeline requires LLM configuration that may not be available in the MCP context."""
question = arguments["question"]
days = arguments.get("days", 7)
# Perform a search to give the user something useful immediately
result = await _handle_search_events({"entity": "", "days": days, "limit": 50})
base_text = result[0].text if result else ""
text = (
f"You asked: '{question}'\n\n"
f"Here are the most recent {min(50, base_text.count(chr(10)) - 1)} events from the last {days} days:\n\n"
f"{base_text}\n\n"
f"Tip: Use the 'search_events' tool with specific filters (services, operation, result) "
f"to narrow down the dataset before asking follow-up questions."
)
return [TextContent(type="text", text=text)]
# ---------------------------------------------------------------------------
# Entry point
# ---------------------------------------------------------------------------
async def main():
async with stdio_server() as (read_stream, write_stream):
await app.run(read_stream, write_stream, app.create_initialization_options())