Reddit Buddy MCP

/** * Reddit authentication manager */ import { homedir, platform } from 'os'; import { join } from 'path'; import { promises as fs } from 'fs'; export interface AuthConfig { clientId: string; clientSecret: string; // Required for script apps username?: string; // For script app auth password?: string; // Never stored, only used temporarily accessToken?: string; refreshToken?: string; expiresAt?: number; scope?: string; userAgent?: string; } export class AuthManager { private config: AuthConfig | null = null; private configPath: string; constructor() { this.configPath = this.getConfigPath(); } /** * Load authentication configuration */ async load(): Promise<AuthConfig | null> { // First check environment variables const envConfig = this.loadFromEnv(); if (envConfig) { this.config = envConfig; return this.config; } // Then check config file try { const configFile = join(this.configPath, 'auth.json'); const data = await fs.readFile(configFile, 'utf-8'); this.config = JSON.parse(data); // Validate config if (this.config && !this.isValidConfig(this.config)) { console.error('Invalid auth configuration found'); this.config = null; } return this.config; } catch (error) { // No auth configured or invalid file return null; } } /** * Load configuration from environment variables */ private loadFromEnv(): AuthConfig | null { const clientId = this.cleanEnvVar(process.env.REDDIT_CLIENT_ID); const clientSecret = this.cleanEnvVar(process.env.REDDIT_CLIENT_SECRET); const username = this.cleanEnvVar(process.env.REDDIT_USERNAME); const password = this.cleanEnvVar(process.env.REDDIT_PASSWORD); const userAgent = this.cleanEnvVar(process.env.REDDIT_USER_AGENT); // Need at least client ID and secret for script apps if (!clientId || !clientSecret) { return null; } return { clientId, clientSecret, username, password, userAgent: userAgent || 'RedditBuddy/1.0 (by /u/karanb192)' }; } /** * Clean environment variable value * Handles empty strings, undefined, and unresolved template strings */ private cleanEnvVar(value: string | undefined): string | undefined { if (!value) return undefined; const trimmed = value.trim(); // Treat empty strings as undefined if (trimmed === '') return undefined; // Treat unresolved template strings as undefined // (happens when Claude Desktop doesn't have the config value set) if (trimmed.startsWith('${') && trimmed.endsWith('}')) { return undefined; } return trimmed; } /** * Save authentication configuration */ async save(config: AuthConfig): Promise<void> { try { // Ensure directory exists await fs.mkdir(this.configPath, { recursive: true }); // Save config const configFile = join(this.configPath, 'auth.json'); await fs.writeFile( configFile, JSON.stringify(config, null, 2), { mode: 0o600 } // Read/write for owner only ); this.config = config; } catch (error) { throw new Error(`Failed to save auth configuration: ${error}`); } } /** * Get current configuration */ getConfig(): AuthConfig | null { return this.config; } /** * Check if authenticated */ isAuthenticated(): boolean { return this.config !== null && this.config.clientId !== undefined && this.config.clientSecret !== undefined; } /** * Check if token is expired */ isTokenExpired(): boolean { if (!this.config?.expiresAt) return true; return Date.now() >= this.config.expiresAt; } /** * Get access token for Reddit OAuth */ async getAccessToken(): Promise<string | null> { if (!this.config) return null; // For script apps, we can use app-only auth if (!this.config.accessToken || this.isTokenExpired()) { await this.refreshAccessToken(); } return this.config.accessToken || null; } /** * Refresh access token using client credentials */ async refreshAccessToken(): Promise<void> { if (!this.config?.clientId || !this.config?.clientSecret) { throw new Error('No client credentials configured'); } try { // Reddit script apps use password grant type const auth = Buffer.from(`${this.config.clientId}:${this.config.clientSecret}`).toString('base64'); let body: string; if (this.config.username && this.config.password) { // Use password grant for authenticated requests (100 req/min) body = new URLSearchParams({ grant_type: 'password', username: this.config.username, password: this.config.password, }).toString(); } else { // Use client credentials grant for anonymous requests (still better than no auth) body = new URLSearchParams({ grant_type: 'client_credentials', }).toString(); } const response = await fetch('https://www.reddit.com/api/v1/access_token', { method: 'POST', headers: { 'Authorization': `Basic ${auth}`, 'Content-Type': 'application/x-www-form-urlencoded', 'User-Agent': this.config.userAgent || 'RedditBuddy/1.0 (by /u/karanb192)' }, body }); if (!response.ok) { const error = await response.text(); throw new Error(`Failed to get access token: ${response.status} - ${error}`); } const data = await response.json() as { access_token: string; token_type: string; expires_in: number; scope: string; }; // Update config this.config.accessToken = data.access_token; this.config.expiresAt = Date.now() + (data.expires_in * 1000); this.config.scope = data.scope; // Never save password to disk const configToSave = { ...this.config }; delete configToSave.password; // Save updated config await this.save(configToSave); } catch (error) { throw new Error(`Failed to refresh access token: ${error}`); } } /** * Clear authentication */ async clear(): Promise<void> { this.config = null; try { const configFile = join(this.configPath, 'auth.json'); await fs.unlink(configFile); } catch { // File might not exist } } /** * Get headers for Reddit API requests */ async getHeaders(): Promise<Record<string, string>> { const headers: Record<string, string> = { 'User-Agent': 'RedditBuddy/1.0 (by /u/karanb192)', 'Accept': 'application/json', 'Accept-Language': 'en-US,en;q=0.9', 'Cache-Control': 'no-cache' }; const token = await this.getAccessToken(); if (token) { headers['Authorization'] = `Bearer ${token}`; } return headers; } /** * Get rate limit based on auth status */ getRateLimit(): number { if (!this.isAuthenticated()) { return 10; // No auth at all } // Full auth with username/password: 100, app-only: 60 return (this.config?.username && this.config?.password) ? 100 : 60; } /** * Get cache TTL based on auth status (in ms) */ getCacheTTL(): number { return this.isAuthenticated() ? 5 * 60 * 1000 // 5 minutes for authenticated : 15 * 60 * 1000; // 15 minutes for unauthenticated } /** * Check if we have full authentication (with user credentials) */ hasFullAuth(): boolean { return this.isAuthenticated() && !!this.config?.username && !!this.config?.password; } /** * Get auth mode string for display */ getAuthMode(): string { if (!this.isAuthenticated()) { return 'Anonymous'; } return this.hasFullAuth() ? 'Authenticated' : 'App-Only'; } /** * Private: Get configuration directory path based on OS */ private getConfigPath(): string { const home = homedir(); switch (platform()) { case 'win32': return join( process.env.APPDATA || join(home, 'AppData', 'Roaming'), 'reddit-mcp-buddy' ); case 'darwin': return join(home, 'Library', 'Application Support', 'reddit-mcp-buddy'); default: // linux and others return join( process.env.XDG_CONFIG_HOME || join(home, '.config'), 'reddit-mcp-buddy' ); } } /** * Private: Validate configuration */ private isValidConfig(config: any): config is AuthConfig { return config && typeof config.clientId === 'string' && config.clientId.length > 0 && typeof config.clientSecret === 'string' && config.clientSecret.length > 0; } /** * Setup wizard for authentication */ static async runSetupWizard(): Promise<AuthConfig> { console.log('\n🚀 Reddit MCP Buddy Authentication Setup\n'); console.log('This will help you set up authentication for 10x more requests.\n'); console.log('Step 1: Create a Reddit App'); console.log(' 1. Go to: https://www.reddit.com/prefs/apps'); console.log(' 2. Click "Create App" or "Create Another App"'); console.log(' 3. Fill in the following:'); console.log(' - Name: Reddit MCP Buddy (or anything you like)'); console.log(' - App type: Select "script"'); console.log(' - Description: Personal use'); console.log(' - About URL: (leave blank)'); console.log(' - Redirect URI: http://localhost:8080'); console.log(' 4. Click "Create app"\n'); console.log('Step 2: Copy your Client ID'); console.log(' - Find it under "personal use script"'); console.log(' - It looks like: XaBcDeFgHiJkLm\n'); // In a real implementation, we'd use a prompt library here console.log('Please enter your Client ID and press Enter:'); // This is a placeholder - in real implementation, use readline or a prompt library const clientId = 'YOUR_CLIENT_ID_HERE'; // Validate client ID format if (!/^[A-Za-z0-9_-]{10,30}$/.test(clientId)) { throw new Error('Invalid Client ID format'); } // This method is deprecated - use CLI setup instead throw new Error('Please use "reddit-mcp-buddy --auth" for authentication setup'); } }