Function withObserve

withObserve<TEvent = unknown, TResult = unknown>(
handler: LambdaHandler<TEvent, TResult>,
): LambdaHandler<TEvent, TResult>

Wrap an AWS Lambda handler with automatic trace flushing

Always flushes before returning - Lambda freezes the container immediately after the handler returns, so this is required.

Type Parameters

TEvent = unknown
TResult = unknown

Parameters

handler: LambdaHandler<TEvent, TResult>
Your Lambda handler function

Returns LambdaHandler<TEvent, TResult>

Wrapped handler that auto-flushes traces

Example

// API Gateway event
export const handler = withObserve(async (event) => {
  const body = JSON.parse(event.body);
  const openai = observe(new OpenAI());
  const result = await openai.chat.completions.create({
    model: 'gpt-4',
    messages: [{ role: 'user', content: body.message }],
  });
  return {
    statusCode: 200,
    body: JSON.stringify(result.choices[0].message),
  };
});

Example

// With typed events
import type { APIGatewayProxyEvent, APIGatewayProxyResult } from 'aws-lambda';

export const handler = withObserve<APIGatewayProxyEvent, APIGatewayProxyResult>(
  async (event, context) => {
    return { statusCode: 200, body: 'OK' };
  }
);