app.py•16 kB
import os
import asyncio
import discord
from discord.ext import commands
from fastapi import FastAPI
from fastmcp import FastMCP
from fastmcp.server.auth import BearerAuthProvider
from fastmcp.server.auth.providers.bearer import RSAKeyPair
from fastmcp.server.dependencies import get_access_token
import uvicorn
from dotenv import load_dotenv
import logging
from datetime import datetime
import jwt
# Load environment variables
load_dotenv()
# --------------------------------
# Setup Audit Logging
# --------------------------------
logging.basicConfig(
filename="audit.log",
level=logging.INFO,
format="%(message)s"
)
def log_audit(tool: str, user_id: str, args: dict, success: bool, error: str = None):
entry = {
"timestamp": datetime.utcnow().isoformat(),
"tool": tool,
"user_id": user_id,
"args": args,
"success": success
}
if error:
entry["error"] = error
logging.info(entry)
# Helper function to create a temporary bot connection
async def create_temp_bot(token: str) -> commands.Bot:
"""Create a temporary bot instance for a single operation"""
intents = discord.Intents.default()
intents.message_content = True
bot = commands.Bot(command_prefix="!", intents=intents)
# Start the bot and wait for it to be ready
await bot.start(token)
return bot
async def cleanup_bot(bot: commands.Bot):
"""Clean up a temporary bot instance"""
if bot and not bot.is_closed():
await bot.close()
def get_discord_token() -> str:
"""Extract Discord token from authenticated JWT"""
access_token = get_access_token()
# Try to get discord_token from additional_claims if available
if hasattr(access_token, 'additional_claims') and access_token.additional_claims:
discord_token = access_token.additional_claims.get("discord_token")
if discord_token:
return discord_token
# Fallback: decode the JWT directly to get claims
try:
decoded = jwt.decode(access_token.token, options={"verify_signature": False})
discord_token = decoded.get("discord_token")
if discord_token:
return discord_token
except:
pass
raise ValueError("No Discord token found in authentication")
# --------------------------------
# Setup Authentication
# --------------------------------
# Generate RSA key pair for development (use external IdP for production)
key_pair = RSAKeyPair.generate()
# Configure Bearer Token authentication
auth = BearerAuthProvider(
public_key=key_pair.public_key,
issuer="https://discord-mcp-server.local",
audience="discord-mcp-server"
)
# --------------------------------
# Set up FastAPI + FastMCP with Authentication
# --------------------------------
app = FastAPI()
mcp = FastMCP(name="Discord MCP Server", auth=auth)
# --------------------------------
# Token Generation Utility
# --------------------------------
def generate_access_token(discord_token: str, user_id: str = "discord-user") -> str:
"""Generate a JWT access token containing the Discord token"""
return key_pair.create_token(
subject=user_id,
issuer="https://discord-mcp-server.local",
audience="discord-mcp-server",
additional_claims={
"discord_token": discord_token,
"permissions": ["discord:read", "discord:write", "discord:moderate"]
},
expires_in_seconds=3600 # 1 hour
)
# --------------------------------
# MCP Tool: send_message
# --------------------------------
@mcp.tool
async def send_message(channel_id: str, message: str) -> dict:
"""
Send a message to a specific Discord channel.
Args:
channel_id (str): The Discord channel ID to send the message to
message (str): The message content to send
Returns:
dict: Success response with message details or error message
"""
bot = None
try:
# Get Discord token from authenticated JWT
access_token = get_access_token()
discord_token = get_discord_token()
tool_name = "send_message"
args = {"channel_id": channel_id, "message": message}
bot = await create_temp_bot(discord_token)
channel = bot.get_channel(int(channel_id)) or await bot.fetch_channel(int(channel_id))
sent = await channel.send(message)
result = {
"status": "success",
"message_id": sent.id,
"channel_id": sent.channel.id,
"timestamp": sent.created_at.isoformat()
}
log_audit(tool_name, access_token.client_id, args, success=True)
return result
except ValueError as e:
return {"error": str(e)}
except Exception as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args if 'args' in locals() else {}, success=False, error=str(e))
return {"error": str(e)}
finally:
if bot:
await cleanup_bot(bot)
@mcp.tool
async def get_messages(channel_id: str, limit: int = 10) -> dict:
"""
Fetches the last `limit` messages from a Discord channel.
Args:
channel_id (str): The channel to fetch messages from.
limit (int): Number of messages to fetch (default: 10).
Returns:
dict: A list of message dictionaries or an error message.
"""
bot = None
try:
# Get Discord token from authenticated JWT
access_token = get_access_token()
discord_token = get_discord_token()
tool_name = "get_messages"
args = {"channel_id": channel_id, "limit": limit}
bot = await create_temp_bot(discord_token)
channel = bot.get_channel(int(channel_id)) or await bot.fetch_channel(int(channel_id))
# Check if it's a text channel
if not isinstance(channel, (discord.TextChannel, discord.Thread)):
return {"error": "Invalid channel type. Must be a text or thread channel."}
# Retrieve messages (returns async iterator)
messages = await channel.history(limit=limit).flatten()
# Build structured output
result = {
"messages": [
{
"id": str(msg.id),
"author": str(msg.author),
"content": msg.content,
"timestamp": msg.created_at.isoformat()
}
for msg in messages
]
}
log_audit(tool_name, access_token.client_id, args, success=True)
return result
except discord.Forbidden:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error="Missing permission to read messages in that channel.")
return {"error": "Missing permission to read messages in that channel."}
except discord.HTTPException as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Discord API error: {str(e)}")
return {"error": f"Discord API error: {str(e)}"}
except Exception as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Unexpected error: {str(e)}")
return {"error": f"Unexpected error: {str(e)}"}
finally:
if bot:
await cleanup_bot(bot)
@mcp.tool
async def get_channel_info(channel_id: str) -> dict:
"""
Retrieves metadata about a given Discord channel.
Args:
channel_id (str): The channel ID to query.
Returns:
dict: Channel metadata or error message.
"""
bot = None
try:
# Get Discord token from authenticated JWT
access_token = get_access_token()
discord_token = get_discord_token()
tool_name = "get_channel_info"
args = {"channel_id": channel_id}
bot = await create_temp_bot(discord_token)
channel = bot.get_channel(int(channel_id)) or await bot.fetch_channel(int(channel_id))
# Determine type
channel_type = (
"text" if isinstance(channel, discord.TextChannel)
else "voice" if isinstance(channel, discord.VoiceChannel)
else "thread" if isinstance(channel, discord.Thread)
else "category" if isinstance(channel, discord.CategoryChannel)
else "unknown"
)
# Build metadata
info = {
"id": str(channel.id),
"name": channel.name,
"type": channel_type,
"guild_id": str(channel.guild.id),
"guild_name": channel.guild.name,
"position": channel.position,
"created_at": channel.created_at.isoformat(),
}
# Optional fields (text-only)
if isinstance(channel, discord.TextChannel):
info.update({
"topic": channel.topic,
"nsfw": channel.is_nsfw(),
"slowmode_delay": channel.slowmode_delay
})
log_audit(tool_name, access_token.client_id, args, success=True)
return info
except discord.NotFound:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error="Channel not found.")
return {"error": "Channel not found."}
except discord.Forbidden:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error="Bot doesn't have permission to access this channel.")
return {"error": "Bot doesn't have permission to access this channel."}
except discord.HTTPException as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Discord API error: {str(e)}")
return {"error": f"Discord API error: {str(e)}"}
except Exception as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Unexpected error: {str(e)}")
return {"error": f"Unexpected error: {str(e)}"}
finally:
if bot:
await cleanup_bot(bot)
@mcp.tool
async def search_messages(channel_id: str, query: str, limit: int = 20) -> dict:
"""
Searches recent messages in a Discord channel containing a keyword.
Args:
channel_id (str): ID of the Discord channel.
query (str): Keyword to search in message content.
limit (int): Max messages to return (default: 20).
Returns:
dict: List of matched messages or error.
"""
bot = None
try:
# Get Discord token from authenticated JWT
access_token = get_access_token()
discord_token = get_discord_token()
tool_name = "search_messages"
args = {"channel_id": channel_id, "query": query, "limit": limit}
bot = await create_temp_bot(discord_token)
channel = bot.get_channel(int(channel_id)) or await bot.fetch_channel(int(channel_id))
if not isinstance(channel, (discord.TextChannel, discord.Thread)):
return {"error": "Invalid channel type. Must be a text or thread channel."}
history = await channel.history(limit=100).flatten() # Fetch more to search through
matches = [
{
"id": str(msg.id),
"author": str(msg.author),
"content": msg.content,
"timestamp": msg.created_at.isoformat()
}
for msg in history
if query.lower() in msg.content.lower()
]
log_audit(tool_name, access_token.client_id, args, success=True)
return {"matches": matches[:limit]}
except discord.Forbidden:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error="Bot lacks permission to read messages in this channel.")
return {"error": "Bot lacks permission to read messages in this channel."}
except discord.HTTPException as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Discord API error: {str(e)}")
return {"error": f"Discord API error: {str(e)}"}
except Exception as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Unexpected error: {str(e)}")
return {"error": f"Unexpected error: {str(e)}"}
finally:
if bot:
await cleanup_bot(bot)
@mcp.tool
async def moderate_content(channel_id: str, message_ids: list[str]) -> dict:
"""
Deletes specific messages in a channel.
Args:
channel_id (str): The ID of the channel.
message_ids (list[str]): List of message IDs to delete.
Returns:
dict: Status of deleted messages or error.
"""
bot = None
try:
# Get Discord token from authenticated JWT
access_token = get_access_token()
discord_token = get_discord_token()
tool_name = "moderate_content"
args = {"channel_id": channel_id, "message_ids": message_ids}
deleted = []
failed = []
bot = await create_temp_bot(discord_token)
channel = bot.get_channel(int(channel_id)) or await bot.fetch_channel(int(channel_id))
for mid in message_ids:
try:
msg = await channel.fetch_message(int(mid))
await msg.delete()
deleted.append(mid)
except discord.NotFound:
failed.append({"id": mid, "error": "Not found"})
except discord.Forbidden:
failed.append({"id": mid, "error": "Permission denied"})
except discord.HTTPException as e:
failed.append({"id": mid, "error": str(e)})
log_audit(tool_name, access_token.client_id, args, success=True)
return {
"status": "partial" if failed else "success",
"deleted": deleted,
"failed": failed
}
except discord.Forbidden:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error="Bot lacks permission to manage messages in this channel.")
return {"error": "Bot lacks permission to manage messages in this channel."}
except discord.HTTPException as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Discord API error: {str(e)}")
return {"error": f"Discord API error: {str(e)}"}
except Exception as e:
log_audit(tool_name, access_token.client_id if 'access_token' in locals() else "unknown", args, success=False, error=f"Unexpected error: {str(e)}")
return {"error": f"Unexpected error: {str(e)}"}
finally:
if bot:
await cleanup_bot(bot)
# --------------------------------
# Start MCP Server
# --------------------------------
def start():
"""Start the MCP server with authentication"""
print("🚀 Starting Authenticated Discord MCP Server...")
print("🔐 Authentication: Bearer Token (JWT)")
print("📝 Available tools:")
print(" - send_message: Send messages to Discord channels")
print(" - get_messages: Fetch recent messages from channels")
print(" - get_channel_info: Get channel metadata")
print(" - search_messages: Search for messages containing keywords")
print(" - moderate_content: Delete specific messages")
print("🔗 Server will run on http://localhost:8000")
print("\n🔑 To generate an access token, use:")
print(" python -c \"from app import generate_access_token; print(generate_access_token('YOUR_DISCORD_BOT_TOKEN'))\"")
uvicorn.run(app, host="0.0.0.0", port=8000)
if __name__ == "__main__":
start()