AWS Bedrock Typescript

index.ts

import {
  BedrockRuntimeClient,
  InvokeModelCommand,
} from '@aws-sdk/client-bedrock-runtime';
import { APIGatewayProxyEventV2, APIGatewayProxyResultV2 } from 'aws-lambda';

const client = new BedrockRuntimeClient({});

export const handler = async (
  event: APIGatewayProxyEventV2,
): Promise<APIGatewayProxyResultV2> => {
  console.log({
    message: 'Event received',
    data: JSON.stringify(event),
  });

  if (event.requestContext.http.method !== 'POST') {
    return 'Only POST method is allowed';
  }

  try {
    const { prompt, temperature } = JSON.parse(event.body);

    if (!prompt || prompt.length < 10) {
      return 'The `prompt` param must be set in the request body and must have at leat 10 chars';
    }

    const temp = parseFloat(temperature.replace(',', '.'));
    if (temperature && isNaN(temp)) {
      return 'The `temperature` param must be a number';
    }

    const maxTokens = process.env.MAX_TOKENS;

    const command = new InvokeModelCommand({
      modelId: 'ai21.j2-ultra-v1',
      body: JSON.stringify({
        prompt,
        maxTokens: maxTokens ? parseInt(maxTokens, 10) : 1525,
        temperature: temp || 0.7,
        topP: 1,
      }),
      accept: 'application/json',
      contentType: 'application/json',
    });

    const response = await client.send(command);
    const result = JSON.parse(Buffer.from(response.body).toString());

    console.log({
      message: 'Response from Bedrock',
      data: JSON.stringify(result),
    });

    return result.completions[0].data.text;
  } catch (error) {
    console.error({
      message: error.message,
      data: error,
    });
    return 'Something went wrong. Please, try again or contact the admin';
  }
};