COMPEON Lambda Helpers

Useful functions that will probably be used across all Lambda functions.

Note: Type definitions in this README are meant as a help and do not strictly follow TypeScript or Flow conventions.

handleError(error: any, status?: number): Object

Used to log the provided error to cloudwatch. Returns AWS Lambda conform response object. If error is not a string, it gets JSON-stringified. status defaults to 500.

Example:

handleError('not found', 404)
// => logs 'not found' to cloudwatch console
// => { body: 'not found', statusCode: 404 }

axiosErrorHandler(axiosResponse: Object): Object

Mostly used inside catch of an axios request. Extracts error from the response and calls handleError with it. Note: Will only work with responses that follow the structure of an axios response.

Example:

axios.get(apiUrl)
  .then(someResponseHandler)
  .catch(axiosErrorHandler)

okayResponse(body?: string|object): Object

Returns an AWS Lambda conform response with the preferred body. body defaults to 'ok'.

Example:

okayResponse()
// => { body: 'ok, statusCode: 200 }

// May also be used as a last handler in a promise chain to directly transform the previous' handlers response as the response of the Lambda itself:
exports.lambda_handler = (event) => {
  // omitted ...

  return axios.get(apiUrl)
    .then(someResponseHandler)
    .then(okayResponse)
}

// If an empty response instead of the previous body is explicitly wanted:
  return axios.get(apiUrl)
    .then(someResponseHandler)
    .then(() => okayResponse())