YouTube Transcript MCP Server

// KV Namespace binding, e.g., from wrangler.toml: TRANSCRIPT_CACHE // Ensure this is bound in your Cloudflare Worker environment. const SUCCESSFUL_TRANSCRIPT_TTL_SECONDS = 60 * 60 * 24 * 7; // 7 days const ERROR_RESPONSE_TTL_SECONDS = 60 * 5; // 5 minutes function getTranscriptCacheKey(videoId: string, language: string): string { return `transcript:${videoId}:${language}`; } /** * Retrieves a cached transcript from KV. * @param env The Worker environment object containing the KV namespace. * @param videoId The YouTube video ID. * @param language The language code for the transcript. * @returns The cached transcript text, or null if not found. */ export async function getCachedTranscript( env: any, videoId: string, language: string ): Promise<string | null> { if (!env.TRANSCRIPT_CACHE) { console.warn('TRANSCRIPT_CACHE namespace not bound in environment.'); return null; } const cacheKey = getTranscriptCacheKey(videoId, language); try { return await env.TRANSCRIPT_CACHE.get(cacheKey); } catch (e: any) { console.error(`Error getting from KV (${cacheKey}): ${e.message}`); return null; } } /** * Stores a transcript (or an error message) in KV with appropriate TTL. * @param env The Worker environment object containing the KV namespace. * @param videoId The YouTube video ID. * @param language The language code for the transcript. * @param data The transcript text or error message to cache. * @param isError True if the data being cached is an error message, false otherwise. */ export async function setCachedTranscript( env: any, videoId: string, language: string, data: string, isError: boolean ): Promise<void> { if (!env.TRANSCRIPT_CACHE) { console.warn('TRANSCRIPT_CACHE namespace not bound in environment.'); return; } const cacheKey = getTranscriptCacheKey(videoId, language); const ttl = isError ? ERROR_RESPONSE_TTL_SECONDS : SUCCESSFUL_TRANSCRIPT_TTL_SECONDS; try { await env.TRANSCRIPT_CACHE.put(cacheKey, data, { expirationTtl: ttl }); } catch (e: any) { console.error(`Error putting to KV (${cacheKey}): ${e.message}`); } } // --- Analytics Caching Functions --- function getVideoAnalyticsCacheKey(videoId: string): string { return `analytics:videos:${videoId}`; } function getDailyRequestsAnalyticsCacheKey(): string { const today = new Date(); const year = today.getUTCFullYear(); const month = (today.getUTCMonth() + 1).toString().padStart(2, '0'); // Months are 0-indexed const day = today.getUTCDate().toString().padStart(2, '0'); return `analytics:requests:${year}-${month}-${day}`; } /** * Increments the request count for a specific video ID in KV. * @param env The Worker environment object containing the KV namespace. * @param videoId The YouTube video ID. */ export async function incrementVideoRequestCount(env: any, videoId: string): Promise<void> { if (!env.TRANSCRIPT_CACHE) { console.warn('TRANSCRIPT_CACHE namespace not bound for analytics.'); return; } const cacheKey = getVideoAnalyticsCacheKey(videoId); try { const currentValue = await env.TRANSCRIPT_CACHE.get(cacheKey); const count = currentValue ? parseInt(currentValue, 10) : 0; if (isNaN(count)) { console.warn(`Invalid count for ${cacheKey}: ${currentValue}. Resetting to 1.`); await env.TRANSCRIPT_CACHE.put(cacheKey, '1'); } else { await env.TRANSCRIPT_CACHE.put(cacheKey, (count + 1).toString()); } } catch (e: any) { console.error(`Error incrementing video request count (${cacheKey}): ${e.message}`); } } /** * Tracks the daily request count in KV. * @param env The Worker environment object containing the KV namespace. */ export async function trackDailyRequests(env: any): Promise<void> { if (!env.TRANSCRIPT_CACHE) { console.warn('TRANSCRIPT_CACHE namespace not bound for analytics.'); return; } const cacheKey = getDailyRequestsAnalyticsCacheKey(); try { const currentValue = await env.TRANSCRIPT_CACHE.get(cacheKey); const count = currentValue ? parseInt(currentValue, 10) : 0; if (isNaN(count)) { console.warn(`Invalid count for ${cacheKey}: ${currentValue}. Resetting to 1.`); await env.TRANSCRIPT_CACHE.put(cacheKey, '1'); } else { await env.TRANSCRIPT_CACHE.put(cacheKey, (count + 1).toString()); } } catch (e: any) { console.error(`Error tracking daily requests (${cacheKey}): ${e.message}`); } }