feat: MCP Client plugin (Task 5.17) - integrate external MCP servers for AI agents

- New plugin app/plugins/builtins/mcp_client/ with server config CRUD - Models: McpServerConfig with TenantMixin (name, url, api_token, enabled) - Routes: GET/POST/PATCH/DELETE /api/v1/mcp-client/servers - Routes: GET /servers/{id}/tools, POST /servers/{id}/execute - client.py: async MCP client using httpx for external server calls - tool_registry_integration.py: registers external MCP tools in AI tool registry - Migration: 0001_initial.sql for mcp_server_configs table - Frontend: mcpClient.ts API client with React Query hooks - Frontend: MCP Client settings UI in SettingsMcp.tsx (server CRUD, tool viewing) - Tests: 8 tests covering CRUD, auth, tool registry integration
2026-07-23 23:02:07 +02:00
parent 9d4f701a25
commit 317d5c81f8
10 changed files with 867 additions and 0 deletions
@@ -0,0 +1,94 @@
+"""Integrates external MCP server tools into the AI Assistant tool_registry.
+
+When the MCP Client plugin activates, it loads all enabled MCP server configs,
+fetches their tool lists, and registers each tool in the global ToolRegistry.
+Agents can then call external MCP tools like native tools.
+"""
+
+from __future__ import annotations
+
+import logging
+import uuid
+from typing import Any
+
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.plugins.builtins.ai_assistant.tool_registry import get_tool_registry
+from app.plugins.builtins.mcp_client.client import McpClient
+from app.plugins.builtins.mcp_client.models import McpServerConfig as McpServerConfigModel
+
+logger = logging.getLogger(__name__)
+
+PLUGIN_NAME = "mcp_client"
+
+
+def _make_tool_name(server_name: str, tool_name: str) -> str:
+    """Generate a unique tool name: mcp__{server}__{tool}."""
+    safe_server = server_name.replace(" ", "_").replace("-", "_").lower()
+    return f"mcp__{safe_server}__{tool_name}"
+
+
+def _make_handler(server_cfg: McpServerConfigModel, tool_name: str):
+    """Create an async handler that calls the external MCP server."""
+
+    async def _handler(arguments: dict[str, Any], context: dict[str, Any]) -> str:
+        client = McpClient(base_url=server_cfg.url, api_token=server_cfg.api_token)
+        try:
+            resp = await client.execute_tool(tool_name, arguments)
+            if resp.success:
+                import json
+                result = resp.result if resp.result is not None else {}
+                return json.dumps(result) if isinstance(result, dict) else str(result)
+            return f"Error: {resp.error or 'Unknown error'}"
+        except Exception as exc:
+            logger.exception("MCP tool execution failed: %s/%s", server_cfg.name, tool_name)
+            return f"Error: {exc}"
+
+    return _handler
+
+
+async def sync_external_tools(db: AsyncSession, tenant_id: uuid.UUID) -> int:
+    """Fetch tools from all enabled MCP servers and register them in the tool registry.
+
+    Returns the number of tools registered.
+    """
+    registry = get_tool_registry()
+    # Unregister previous tools from this plugin
+    registry.unregister_plugin(PLUGIN_NAME)
+
+    stmt = select(McpServerConfigModel).where(
+        McpServerConfigModel.tenant_id == tenant_id,
+        McpServerConfigModel.enabled.is_(True),
+    )
+    result = await db.execute(stmt)
+    configs = result.scalars().all()
+
+    count = 0
+    for cfg in configs:
+        try:
+            client = McpClient(base_url=cfg.url, api_token=cfg.api_token, timeout=10.0)
+            tools_resp = await client.list_tools()
+            for tool in tools_resp.tools:
+                tool_name = _make_tool_name(cfg.name, tool.name)
+                registry.register(
+                    name=tool_name,
+                    description=f"[MCP:{cfg.name}] {tool.description}",
+                    parameters=tool.parameters if isinstance(tool.parameters, dict) else {},
+                    handler=_make_handler(cfg, tool.name),
+                    plugin_name=PLUGIN_NAME,
+                    required_permission="mcp-client:read",
+                    category="mcp-external",
+                )
+                count += 1
+            logger.info("Registered %d tools from MCP server %s", len(tools_resp.tools), cfg.name)
+        except Exception as exc:
+            logger.warning("Failed to sync tools from MCP server %s: %s", cfg.name, exc)
+
+    return count
+
+
+def unregister_all_external_tools() -> None:
+    """Remove all MCP client tools from the registry."""
+    registry = get_tool_registry()
+    registry.unregister_plugin(PLUGIN_NAME)