mcp-discord/src/transport.ts

591 lines
27 KiB
TypeScript

import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import express, { Request, Response } from "express";
import { toolList } from './toolList.js';
import {
createToolContext,
loginHandler,
sendMessageHandler,
getForumChannelsHandler,
createForumPostHandler,
getForumPostHandler,
replyToForumHandler,
deleteForumPostHandler,
createTextChannelHandler,
deleteChannelHandler,
readMessagesHandler,
getServerInfoHandler,
addReactionHandler,
addMultipleReactionsHandler,
removeReactionHandler,
deleteMessageHandler,
createWebhookHandler,
sendWebhookMessageHandler,
editWebhookHandler,
deleteWebhookHandler
} from './tools/tools.js';
import { Client, GatewayIntentBits } from "discord.js";
import { info, error } from './logger.js';
export interface MCPTransport {
start(server: Server): Promise<void>;
stop(): Promise<void>;
}
export class StdioTransport implements MCPTransport {
private transport: StdioServerTransport | null = null;
async start(server: Server): Promise<void> {
this.transport = new StdioServerTransport();
await server.connect(this.transport);
}
async stop(): Promise<void> {
if (this.transport) {
await this.transport.close();
this.transport = null;
}
}
}
export class StreamableHttpTransport implements MCPTransport {
private app: express.Application;
private server: Server | null = null;
private httpServer: any = null;
private transport: StreamableHTTPServerTransport | null = null;
private toolContext: ReturnType<typeof createToolContext> | null = null;
private sessionId: string = '';
constructor(private port: number = 8080) {
this.app = express();
this.app.use(express.json());
this.setupEndpoints();
this.sessionId = `session_${Date.now()}_${Math.random().toString(36).substring(2, 10)}`;
info(`Created HTTP transport with session ID: ${this.sessionId}`);
}
private setupEndpoints() {
// Handler for POST requests
this.app.post('/mcp', (req: Request, res: Response) => {
info('Received MCP request: ' + JSON.stringify(req.body));
this.handleMcpRequest(req, res).catch(error => {
error('Unhandled error in MCP request: ' + String(error));
});
});
// Handler for non-POST methods
this.app.all('/mcp', (req: Request, res: Response) => {
if (req.method !== 'POST') {
res.status(405).json({
jsonrpc: '2.0',
error: {
code: -32000,
message: 'Method not allowed. Use POST.',
},
id: null,
});
}
});
}
private async handleMcpRequest(req: Request, res: Response) {
try {
if (!this.server) {
return res.json({
jsonrpc: '2.0',
error: {
code: -32603,
message: 'Server not initialized',
},
id: req.body?.id || null,
});
}
info(`Request body (session ${this.sessionId}): ${JSON.stringify(req.body)}`);
// Handle all tool requests in a generic way
if (!req.body.method) {
return res.status(400).json({
jsonrpc: '2.0',
error: {
code: -32600,
message: 'Invalid Request: No method specified',
},
id: req.body?.id || null,
});
}
// Handle all tools directly with proper error handling
try {
const method = req.body.method;
const params = req.body.params || {};
// Make sure toolContext is available for tool methods
if (!this.toolContext && method !== 'list_tools' && method !== 'initialize') {
return res.status(400).json({
jsonrpc: '2.0',
error: {
code: -32603,
message: 'Tool context not initialized. Service may need to be restarted.',
},
id: req.body?.id || null,
});
}
let result;
// Handle each tool method directly
switch (method) {
case 'initialize':
// Handle initialize method for MCP protocol compliance
result = {
protocolVersion: "2025-03-26",
capabilities: {
tools: {
listChanged: false
},
logging: {}
},
serverInfo: {
name: "MCP-Discord",
version: "1.2.0"
}
};
break;
case 'notifications/initialized':
// Client indicates it's ready to begin normal operation
info("Client initialized. Starting normal operations.");
// No result needed for notifications
return res.json({
jsonrpc: "2.0",
result: null,
id: req.body.id
});
case 'tools/list':
// New MCP method name format
result = { tools: toolList };
break;
case 'list_tools':
// Legacy method name for backward compatibility
result = { tools: toolList };
break;
case 'discord_login':
result = await loginHandler(params, this.toolContext!);
// Log client state after login
info(`Client state after login: ${JSON.stringify({
isReady: this.toolContext!.client.isReady(),
hasToken: !!this.toolContext!.client.token,
user: this.toolContext!.client.user ? {
id: this.toolContext!.client.user.id,
tag: this.toolContext!.client.user.tag,
} : null
})}`);
break;
// Make sure Discord client is logged in for other Discord API tools
// but return a proper JSON-RPC error rather than throwing an exception
case 'discord_send':
case 'discord_get_forum_channels':
case 'discord_create_forum_post':
case 'discord_get_forum_post':
case 'discord_reply_to_forum':
case 'discord_delete_forum_post':
case 'discord_create_text_channel':
case 'discord_delete_channel':
case 'discord_read_messages':
case 'discord_get_server_info':
case 'discord_add_reaction':
case 'discord_add_multiple_reactions':
case 'discord_remove_reaction':
case 'discord_delete_message':
case 'discord_create_webhook':
case 'discord_send_webhook_message':
case 'discord_edit_webhook':
case 'discord_delete_webhook':
// Check if client is logged in
if (!this.toolContext!.client.isReady()) {
error(`Client not ready for method ${method}, client state: ${JSON.stringify({
isReady: this.toolContext!.client.isReady(),
hasToken: !!this.toolContext!.client.token,
user: this.toolContext!.client.user ? {
id: this.toolContext!.client.user.id,
tag: this.toolContext!.client.user.tag,
} : null
})}`);
return res.json({
jsonrpc: '2.0',
error: {
code: -32603,
message: 'Discord client not logged in. Please use discord_login tool first.',
},
id: req.body?.id || null,
});
}
// Call appropriate handler based on method
switch (method) {
case 'discord_send':
result = await sendMessageHandler(params, this.toolContext!);
break;
case 'discord_get_forum_channels':
result = await getForumChannelsHandler(params, this.toolContext!);
break;
case 'discord_create_forum_post':
result = await createForumPostHandler(params, this.toolContext!);
break;
case 'discord_get_forum_post':
result = await getForumPostHandler(params, this.toolContext!);
break;
case 'discord_reply_to_forum':
result = await replyToForumHandler(params, this.toolContext!);
break;
case 'discord_delete_forum_post':
result = await deleteForumPostHandler(params, this.toolContext!);
break;
case 'discord_create_text_channel':
result = await createTextChannelHandler(params, this.toolContext!);
break;
case 'discord_delete_channel':
result = await deleteChannelHandler(params, this.toolContext!);
break;
case 'discord_read_messages':
result = await readMessagesHandler(params, this.toolContext!);
break;
case 'discord_get_server_info':
result = await getServerInfoHandler(params, this.toolContext!);
break;
case 'discord_add_reaction':
result = await addReactionHandler(params, this.toolContext!);
break;
case 'discord_add_multiple_reactions':
result = await addMultipleReactionsHandler(params, this.toolContext!);
break;
case 'discord_remove_reaction':
result = await removeReactionHandler(params, this.toolContext!);
break;
case 'discord_delete_message':
result = await deleteMessageHandler(params, this.toolContext!);
break;
case 'discord_create_webhook':
result = await createWebhookHandler(params, this.toolContext!);
break;
case 'discord_send_webhook_message':
result = await sendWebhookMessageHandler(params, this.toolContext!);
break;
case 'discord_edit_webhook':
result = await editWebhookHandler(params, this.toolContext!);
break;
case 'discord_delete_webhook':
result = await deleteWebhookHandler(params, this.toolContext!);
break;
}
break;
case 'ping':
// Add support for heartbeat ping
result = { pong: true };
break;
case 'tools/call':
// Handle new tools/call method format
const toolName = params.name;
const toolArgs = params.arguments || {};
// Check if Discord client is logged in for Discord API tools
if (toolName !== 'discord_login' &&
toolName.startsWith('discord_') &&
!this.toolContext!.client.isReady()) {
error(`Client not ready for tool ${toolName}, client state: ${JSON.stringify({
isReady: this.toolContext!.client.isReady(),
hasToken: !!this.toolContext!.client.token,
user: this.toolContext!.client.user ? {
id: this.toolContext!.client.user.id,
tag: this.toolContext!.client.user.tag,
} : null
})}`);
return res.json({
jsonrpc: '2.0',
error: {
code: -32603,
message: 'Discord client not logged in. Please use discord_login tool first.',
},
id: req.body?.id || null,
});
}
// Call the appropriate handler based on tool name
switch (toolName) {
case 'discord_login':
result = await loginHandler(toolArgs, this.toolContext!);
// Log client state after login
info(`Client state after login: ${JSON.stringify({
isReady: this.toolContext!.client.isReady(),
hasToken: !!this.toolContext!.client.token,
user: this.toolContext!.client.user ? {
id: this.toolContext!.client.user.id,
tag: this.toolContext!.client.user.tag,
} : null
})}`);
break;
case 'discord_send':
result = await sendMessageHandler(toolArgs, this.toolContext!);
break;
case 'discord_get_forum_channels':
result = await getForumChannelsHandler(toolArgs, this.toolContext!);
break;
case 'discord_create_forum_post':
result = await createForumPostHandler(toolArgs, this.toolContext!);
break;
case 'discord_get_forum_post':
result = await getForumPostHandler(toolArgs, this.toolContext!);
break;
case 'discord_reply_to_forum':
result = await replyToForumHandler(toolArgs, this.toolContext!);
break;
case 'discord_delete_forum_post':
result = await deleteForumPostHandler(toolArgs, this.toolContext!);
break;
case 'discord_create_text_channel':
result = await createTextChannelHandler(toolArgs, this.toolContext!);
break;
case 'discord_delete_channel':
result = await deleteChannelHandler(toolArgs, this.toolContext!);
break;
case 'discord_read_messages':
result = await readMessagesHandler(toolArgs, this.toolContext!);
break;
case 'discord_get_server_info':
result = await getServerInfoHandler(toolArgs, this.toolContext!);
break;
case 'discord_add_reaction':
result = await addReactionHandler(toolArgs, this.toolContext!);
break;
case 'discord_add_multiple_reactions':
result = await addMultipleReactionsHandler(toolArgs, this.toolContext!);
break;
case 'discord_remove_reaction':
result = await removeReactionHandler(toolArgs, this.toolContext!);
break;
case 'discord_delete_message':
result = await deleteMessageHandler(toolArgs, this.toolContext!);
break;
case 'discord_create_webhook':
result = await createWebhookHandler(toolArgs, this.toolContext!);
break;
case 'discord_send_webhook_message':
result = await sendWebhookMessageHandler(toolArgs, this.toolContext!);
break;
case 'discord_edit_webhook':
result = await editWebhookHandler(toolArgs, this.toolContext!);
break;
case 'discord_delete_webhook':
result = await deleteWebhookHandler(toolArgs, this.toolContext!);
break;
default:
return res.status(400).json({
jsonrpc: '2.0',
error: {
code: -32601,
message: `Unknown tool: ${toolName}`,
},
id: req.body?.id || null,
});
}
break;
default:
return res.status(400).json({
jsonrpc: '2.0',
error: {
code: -32601,
message: `Method not found: ${method}`,
},
id: req.body?.id || null,
});
}
info(`Request for ${method} handled successfully`);
// Handle the case where tool handlers return { content, isError }
if (result && typeof result === 'object' && 'content' in result) {
// If it's an error from the tool handler
if ('isError' in result && result.isError) {
error(`Tool error response: ${JSON.stringify(result)}`);
return res.json({
jsonrpc: '2.0',
id: req.body.id,
error: {
code: -32603,
message: Array.isArray(result.content)
? result.content.map((item: any) => item.text).join(' ')
: 'Tool execution error'
}
});
}
// Return success result but maintain same format as other RPC methods
const finalResponse = {
jsonrpc: '2.0',
id: req.body.id,
result: result
};
info(`Sending response (session ${this.sessionId}): ${JSON.stringify(finalResponse)}`);
return res.json(finalResponse);
}
// Standard result format
const finalResponse = {
jsonrpc: '2.0',
id: req.body.id,
result: result
};
info(`Sending response (session ${this.sessionId}): ${JSON.stringify(finalResponse)}`);
return res.json(finalResponse);
} catch (err) {
error('Error processing tool request: ' + String(err));
// Handle validation errors
if (err && typeof err === 'object' && 'name' in err && err.name === 'ZodError') {
return res.json({
jsonrpc: '2.0',
error: {
code: -32602,
message: `Invalid parameters: ${err && typeof err === 'object' && 'message' in err ? String((err as any).message) : 'Unknown validation error'}`,
},
id: req.body?.id || null,
});
}
// Handle all other errors
return res.json({
jsonrpc: '2.0',
error: {
code: -32603,
message: err instanceof Error ? err.message : 'Unknown error',
},
id: req.body?.id || null,
});
}
} catch (err) {
error('Error handling MCP request: ' + String(err));
if (!res.headersSent) {
res.json({
jsonrpc: '2.0',
error: {
code: -32603,
message: err instanceof Error ? err.message : 'Internal server error',
},
id: req.body?.id || null,
});
}
}
}
async start(server: Server): Promise<void> {
this.server = server;
info('Starting HTTP transport with server: ' + String(!!this.server));
// Try to get client from the DiscordMCPServer instance
// First, check if the server is passed from DiscordMCPServer
if (server) {
// Try to access client directly from server._context
const anyServer = server as any;
let client: Client | undefined;
if (anyServer._context?.client) {
client = anyServer._context.client;
info('Found client in server._context');
}
// Also check if the server object has client directly
else if (anyServer.client instanceof Client) {
client = anyServer.client;
info('Found client directly on server object');
}
// Look in parent object if available
else if (anyServer._parent?.client instanceof Client) {
client = anyServer._parent.client;
info('Found client in server._parent');
}
if (client) {
this.toolContext = createToolContext(client);
info('Tool context initialized with Discord client');
} else {
// Create a real Discord client instead of a dummy
info('Creating new Discord client for transport');
const newClient = new Client({
intents: [
GatewayIntentBits.Guilds,
GatewayIntentBits.GuildMessages,
GatewayIntentBits.MessageContent,
GatewayIntentBits.GuildMessageReactions
]
});
this.toolContext = createToolContext(newClient);
info('Tool context initialized with new Discord client');
}
}
// Create a stateless transport
this.transport = new StreamableHTTPServerTransport({
sessionIdGenerator: undefined // set to undefined for stateless servers
});
// Connect the transport
await this.server.connect(this.transport);
info('Transport connected');
return new Promise((resolve) => {
this.httpServer = this.app.listen(this.port, '0.0.0.0', () => {
info(`MCP Server listening on 0.0.0.0:${this.port}`);
resolve();
});
});
}
async stop(): Promise<void> {
if (this.transport) {
await this.transport.close();
this.transport = null;
}
if (this.server) {
await this.server.close();
this.server = null;
}
if (this.httpServer) {
return new Promise((resolve) => {
this.httpServer.close(() => {
info('HTTP server closed');
this.httpServer = null;
resolve();
});
});
}
}
}