利用无服务器架构实时转录与翻译

npm install -g aws-cdk

mkdir transcribe-translate
cd transcribe-translate
cdk init app --language typescript

npm install @aws-cdk/aws-s3 @aws-cdk/aws-lambda @aws-cdk/aws-iam @aws-cdk/aws-s3-notifications @aws-cdk/aws-lambda-nodejs

import * as cdk from 'aws-cdk-lib';
import { Construct } from 'constructs';
import * as s3 from 'aws-cdk-lib/aws-s3';
import * as lambda from 'aws-cdk-lib/aws-lambda';
import * as s3n from 'aws-cdk-lib/aws-s3-notifications';
import { NodejsFunction } from 'aws-cdk-lib/aws-lambda-nodejs';
import * as iam from 'aws-cdk-lib/aws-iam';
import * as path from 'path';

export class TranscribeTranslateStack extends cdk.Stack {
  constructor(scope: Construct, id: string, props?: cdk.StackProps) {
    super(scope, id, props);

    // Create the S3 bucket
    const bucket = new s3.Bucket(this, 'UploadBucket', {
      removalPolicy: cdk.RemovalPolicy.DESTROY, // this is OK only for dev
      autoDeleteObjects: true, // this is OK only for dev
    });

    // Create the Transcribe Lambda function
    const transcribeFunction = new NodejsFunction(this, 'TranscribeFunction', {
      runtime: lambda.Runtime.NODEJS_18_X,
      entry: path.join(__dirname, '../lambda/transcribe.mjs'),
      handler: 'handler',
      environment: {
        BUCKET_NAME: bucket.bucketName,
      },
      timeout: cdk.Duration.seconds(900),
    });

    // Grant read/write permissions on S3 objects for the transcribe function
    bucket.grantReadWrite(transcribeFunction, 'transcriptions/*');

    // Additional permissions for Transcribe
    transcribeFunction.addToRolePolicy(new iam.PolicyStatement({
      actions: ['transcribe:StartTranscriptionJob', 'transcribe:GetTranscriptionJob'],
      resources: ['*'],
    }));

    // Add S3 event notification to trigger Transcribe function
    bucket.addEventNotification(s3.EventType.OBJECT_CREATED, new s3n.LambdaDestination(transcribeFunction), {
      prefix: 'audio/',
    });

    // Create the Translate Lambda function
    const translateFunction = new NodejsFunction(this, 'TranslateFunction', {
      runtime: lambda.Runtime.NODEJS_18_X,
      entry: path.join(__dirname, '../lambda/translate.mjs'),
      handler: 'handler',
      environment: {
        BUCKET_NAME: bucket.bucketName,
      },
      timeout: cdk.Duration.seconds(900),
    });

    // Grant read/write permissions on specific S3 objects for the translate function
    bucket.grantRead(translateFunction, 'transcriptions/*');
    bucket.grantReadWrite(translateFunction,'translations/*');

    // Additional permissions for Translate
    translateFunction.addToRolePolicy(new iam.PolicyStatement({
      actions: ['translate:TranslateText'],
      resources: ['*'],
    }));

    // Add S3 event notification to trigger Translate function
    bucket.addEventNotification(s3.EventType.OBJECT_CREATED, new s3n.LambdaDestination(translateFunction), {
      prefix: 'transcriptions/',
    });
  }
}

import { TranscribeClient, StartTranscriptionJobCommand } from '@aws-sdk/client-transcribe';

const transcribeClient = new TranscribeClient();

export const handler = async (event) => {
    const bucket = process.env.BUCKET_NAME;
    const key = event.Records[0].s3.object.key;

    const transcribeParams = {
        TranscriptionJobName: `TranscribeJob-${Date.now()}`,
        LanguageCode: 'en-US',
        Media: {
            MediaFileUri: `s3://${bucket}/${key}`
        },
        OutputBucketName: bucket,
        OutputKey: `transcriptions/${key.split("/").pop()}.json`
    };

    try {
        await transcribeClient.send(new StartTranscriptionJobCommand(transcribeParams));
        console.log('Transcription job started');
    } catch (err) {
        console.error('Error starting transcription job', err);
        return;
    }

};

import { S3Client, GetObjectCommand, PutObjectCommand } from '@aws-sdk/client-s3';
import { TranslateClient, TranslateTextCommand } from '@aws-sdk/client-translate';

const s3Client = new S3Client();
const translateClient = new TranslateClient();

export const handler = async (event) => {
    const bucket = process.env.BUCKET_NAME;
    const key = event.Records[0].s3.object.key;

    // Get the transcription text from S3
    let transcriptionData;
    
    try {
        transcriptionData = await s3Client.send(new GetObjectCommand({
            Bucket: bucket,
            Key: key
        }));
    } catch (err) {
        console.error('Error getting transcription from S3', err);
        return;
    }

    const { results } = JSON.parse(await streamToString(transcriptionData.Body));

    const transcriptionText = results.transcripts.reduce(
        (acc, curr) => acc + curr.transcript, ''
    );
    console.log('Transcription text:', transcriptionText);

    // Translate the transcription
    const translateParams = {
        SourceLanguageCode: 'en',
        TargetLanguageCode: 'it',
        Text: transcriptionText
    };

    console.log(translateParams);

    let translation; 
    
    try{
        translation = await translateClient.send(new TranslateTextCommand(translateParams));
        console.log('Translation:', translation.TranslatedText);
    }catch(err){
        console.error('Error translating text', err);
        return;
    }

    // Save the translation result to S3
    const translationResult = {
        originalText: transcriptionText,
        translatedText: translation.TranslatedText
    };

    try{
        await s3Client.send(new PutObjectCommand({
            Bucket: bucket,
            Key: `translations/${key.split("/").pop()}.it.txt`,
            Body: translationResult.translatedText,
            ContentType: 'text/plain'
        }));
    }catch(err){
        console.error('Error saving translation to S3', err);
        return;
    }

    console.log('Translation saved');
};

// Helper function to convert a stream to a string
const streamToString = (stream) => {
    return new Promise((resolve, reject) => {
        const chunks = [];
        stream.on('data', (chunk) => chunks.push(chunk));
        stream.on('error', reject);
        stream.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')));
    });
};

cdk destroy