feat: add ai service with deepgram and openai (#17)

feat: add DEEPGRAM and OPENAI keys to env

feat: init transcribeAudio with deepgram

feat: add openai

feat: add summarizeTranscript via OPENAI

refactor: use `@env` to access openai key

feat: add generateEpisodeContent

.env.example

@@ -5,3 +5,6 @@ NEXT_PUBLIC_SUPABASE_URL=
 
 SUPABASE_SERVICE_ROLE_KEY=
 SUPABASE_URL=
+
+DEEPGRAM_API_KEY=
+OPENAI_API_KEY=

env.mjs

@@ -15,11 +15,13 @@ const getGitSha = () => {
 };
 
 const envSchema = z.object({
+  DEEPGRAM_API_KEY: z.string().min(1),
   GIT_SHA: z.string().min(1).default(getGitSha()),
   NEXT_PUBLIC_PODCAST_INDEX_API_KEY: z.string().min(1),
   NEXT_PUBLIC_PODCAST_INDEX_SECRET: z.string().min(1),
   NEXT_PUBLIC_SUPABASE_ANON_KEY: z.string().min(1),
   NEXT_PUBLIC_SUPABASE_URL: z.string().min(1),
+  OPENAI_API_KEY: z.string().min(1),
   SUPABASE_SERVICE_ROLE_KEY: z.string().min(1),
   SUPABASE_URL: z.string().min(1),
 });

lib/services/account.ts

@@ -14,6 +14,22 @@ const getUserId = async () => {
   return userQuery.data.user.id;
 };
 
+export const getAccountId = async () => {
+  const supabase = createSupabaseServerClient(cookies());
+
+  const accountQuery = await supabase
+    .from('account')
+    .select('id')
+    .eq('user_id', await getUserId())
+    .single();
+
+  if (accountQuery.error) {
+    throw new Error(accountQuery.error.message);
+  }
+
+  return accountQuery.data.id;
+};
+
 export const fetchAccountAICredits = async () => {
   const supabase = createSupabaseServerClient(cookies());
 

lib/services/ai/deepgram.ts

@@ -0,0 +1,25 @@
+import { env } from '@/env.mjs';
+import { createClient as createDeepgramClient } from '@deepgram/sdk';
+
+const deepgram = createDeepgramClient(env.DEEPGRAM_API_KEY);
+
+export const transcribeAudio = async ({ fileURL }: { fileURL: string }) => {
+  const { result } = await deepgram.listen.prerecorded.transcribeUrl(
+    {
+      url: fileURL,
+    },
+    {
+      diarize: true,
+      model: 'nova-2',
+      smart_format: true,
+    },
+  );
+
+  const transcript = result?.results.channels[0]?.alternatives[0]?.transcript;
+
+  if (!transcript) {
+    throw new Error('No transcript found');
+  }
+
+  return transcript;
+};

lib/services/ai/generate-episode-content.ts

@@ -0,0 +1,67 @@
+import type { Tables } from '@/types/supabase/database';
+
+import {
+  getAccountId,
+  updateAccountAICredits,
+  validateAccountAICredits,
+} from '../account';
+import { createSupabaseServiceClient } from '../supabase/service';
+import { transcribeAudio } from './deepgram';
+import { summarizeEpisodeTranscript } from './openai';
+
+export const generateEpisodeContent = async ({
+  episodeId,
+}: {
+  episodeId: Tables<'episode'>['id'];
+}) => {
+  const initialAiCredits = await validateAccountAICredits();
+  const updatedAiCredits = await updateAccountAICredits(initialAiCredits - 1);
+
+  try {
+    const supabase = createSupabaseServiceClient();
+
+    const episodeQuery = await supabase
+      .from('episode')
+      .select('title, audio_url')
+      .eq('id', episodeId)
+      .single();
+
+    if (episodeQuery.error) {
+      throw new Error(episodeQuery.error.message);
+    }
+
+    const transcript = await transcribeAudio({
+      fileURL: episodeQuery.data.audio_url,
+    });
+
+    const summary = await summarizeEpisodeTranscript({
+      title: episodeQuery.data.title,
+      transcript,
+    });
+
+    const createEpisodeContentQuery = await supabase
+      .from('episode_content')
+      .upsert(
+        {
+          episode: episodeId,
+          text_summary: summary,
+          transcription: transcript,
+          user: await getAccountId(),
+        },
+        {
+          onConflict: 'episode',
+        },
+      )
+      .select('*')
+      .single();
+
+    if (createEpisodeContentQuery.error) {
+      throw new Error(createEpisodeContentQuery.error.message);
+    }
+
+    return createEpisodeContentQuery.data;
+  } catch (error) {
+    await updateAccountAICredits(updatedAiCredits + 1);
+    throw error;
+  }
+};

lib/services/ai/openai.ts

@@ -0,0 +1,28 @@
+import { env } from '@/env.mjs';
+import { OpenAI } from 'openai';
+
+const openai = new OpenAI({ apiKey: env.OPENAI_API_KEY });
+
+export const summarizeEpisodeTranscript = async ({
+  title,
+  transcript,
+}: {
+  title: string;
+  transcript: string;
+}) => {
+  const response = await openai.chat.completions.create({
+    messages: [
+      {
+        content: `Summarize the following transcript from a podcast episode titled as ${title}`,
+        role: 'system',
+      },
+      {
+        content: transcript,
+        role: 'system',
+      },
+    ],
+    model: 'gpt-3.5-turbo-1106',
+  });
+
+  return response.choices[0].message.content;
+};

package.json

@@ -17,13 +17,15 @@
   },
   "prettier": "@vercel/style-guide/prettier",
   "dependencies": {
+    "@deepgram/sdk": "^3.0.1",
     "@radix-ui/react-icons": "^1.3.0",
     "@radix-ui/themes": "^2.0.2",
     "@supabase/ssr": "^0.0.10",
     "@supabase/supabase-js": "^2.39.0",
     "next": "14.0.4",
     "next-themes": "1.0.0-beta.0",
     "ofetch": "^1.3.3",
+    "openai": "^4.20.1",
     "react": "^18",
     "react-dom": "^18",
     "zod": "^3.22.4"