我写了一个typescript Lambda API。如图所示，callback complete记录的位置，lambda在10秒后响应。你也可以在时间戳中看到。

export const handler = async (event, context, callback) => {
  const { headers: { Authorization } } = event

  start = Date.now()

  const auth = await authorizer(Authorization)

  console.log(`Authorizer took ${Date.now() - start} seconds to complete`)

  if (!auth.isAuthenticated) {
    callback(null, { statusCode: 401, body: JSON.stringify("Unauthorized") })
    return
  }

  start = Date.now()
  const associations = await dynamoDb.query({
    // DynamoDB Query params
  }).promise()

  console.log(`DynamoDB query took ${Date.now() - start} seconds to complete`)

  const customers = associations.Items.map(association => association.customer)

  if (customers.length === 0) {
    callback(null, { statusCode: 200, body: JSON.stringify([]) })
    return
  }

  start = Date.now()
  const customerDetails = await pool.query(`XXXXXXXX`)

  console.log(`PostgreSQL query took ${Date.now() - start} milliseconds to complete`)

  const { rows } = customerDetails

  callback(null, { statusCode: 200, body: JSON.stringify(rows) })
  console.log('callback complete')
  return
}