Add missing typeguard exports for event and request type narrowing

index.js

@@ -16,6 +16,12 @@ const {
   isApiGatewayContext,
   isApiGatewayV2Context,
   isAlbContext,
+  isApiGatewayEvent,
+  isApiGatewayV2Event,
+  isAlbEvent,
+  isApiGatewayRequest,
+  isApiGatewayV2Request,
+  isAlbRequest,
 } = require('./lib/typeguards');
 
 class API {
@@ -564,3 +570,9 @@ module.exports.default = module.exports;
 module.exports.isApiGatewayContext = isApiGatewayContext;
 module.exports.isApiGatewayV2Context = isApiGatewayV2Context;
 module.exports.isAlbContext = isAlbContext;
+module.exports.isApiGatewayEvent = isApiGatewayEvent;
+module.exports.isApiGatewayV2Event = isApiGatewayV2Event;
+module.exports.isAlbEvent = isAlbEvent;
+module.exports.isApiGatewayRequest = isApiGatewayRequest;
+module.exports.isApiGatewayV2Request = isApiGatewayV2Request;
+module.exports.isAlbRequest = isAlbRequest;

lib/typeguards.js

@@ -1,19 +1,49 @@
 'use strict';
 
 const isApiGatewayContext = (context) => {
-  return 'identity' in context;
+  return context && 'identity' in context;
 };
 
 const isApiGatewayV2Context = (context) => {
-  return 'http' in context;
+  return context && 'http' in context;
 };
 
 const isAlbContext = (context) => {
-  return 'elb' in context;
+  return context && 'elb' in context;
+};
+
+const isApiGatewayEvent = (event) => {
+  return event && event.requestContext && 'identity' in event.requestContext;
+};
+
+const isApiGatewayV2Event = (event) => {
+  return event && event.requestContext && 'http' in event.requestContext;
+};
+
+const isAlbEvent = (event) => {
+  return event && event.requestContext && 'elb' in event.requestContext;
+};
+
+const isApiGatewayRequest = (req) => {
+  return req && req.requestContext && 'identity' in req.requestContext;
+};
+
+const isApiGatewayV2Request = (req) => {
+  return req && req.requestContext && 'http' in req.requestContext;
+};
+
+const isAlbRequest = (req) => {
+  return req && req.requestContext && 'elb' in req.requestContext;
 };
 
 module.exports = {
   isApiGatewayContext,
   isApiGatewayV2Context,
   isAlbContext,
+  isApiGatewayEvent,
+  isApiGatewayV2Event,
+  isAlbEvent,
+  isApiGatewayRequest,
+  isApiGatewayV2Request,
+  isAlbRequest,
 };