Function lambdaRequestTracker

src/request.ts:13–61

(
  /* istanbul ignore next */
  options: LambdaRequestTrackerOptions = {},
)

 * @param options The request options
 */
export const lambdaRequestTracker = (
  /* istanbul ignore next */
  options: LambdaRequestTrackerOptions = {},
) => (event: LambdaEvent, context: LambdaContext): void => {
  const ctx: ContextMap = {
    awsRequestId: context.awsRequestId,
  };

  // capture api gateway request ID
  const apiRequestId = event.requestContext?.requestId;
  if (apiRequestId) {
    ctx.apiRequestId = apiRequestId;
  }

  // capture any correlation headers sent from upstream callers
  if (event.headers) {
    for (const [header, value] of Object.entries(event.headers)) {
      if (header.toLowerCase().startsWith(CORRELATION_HEADER)) {
        ctx[header] = value;
      }
    }
  }

  // capture the xray trace id if its enabled
  if (process.env[AMAZON_TRACE_ID]) {
    ctx[CORRELATION_TRACE_ID] = process.env[AMAZON_TRACE_ID];
  }

  // set the correlation id if not already set by upstream callers
  /* istanbul ignore next */
  if (!ctx[CORRELATION_ID]) {
    ctx[CORRELATION_ID] = context.awsRequestId;
  }

  // handle custom request level mixins
  if (options.requestMixin) {
    const result = options.requestMixin(event, context);
    for (const key in result) {
      // when the JSON serializer runs, by default it omits undefined properties
      ctx[key] = result[key];
    }
  }

  const storageProvider = options.storageProvider || GlobalContextStorageProvider;
  /* istanbul ignore next */
  if (storageProvider) {
    storageProvider.setContext(ctx);
  }
};