fix(rest): Fix compilation error caused by @types/node

@types/node@8.0.56 introduces a breaking change for URL and our build
fails due to imcompatible types

Author: raymondfeng

package.json

@@ -15,7 +15,7 @@
     "@commitlint/config-angular": "^4.3.0",
     "@commitlint/config-lerna-scopes": "^4.3.0",
     "@types/mocha": "^2.2.44",
-    "@types/node": "^8.0.50",
+    "@types/node": "^8.0.56",
     "@types/request": "^2.0.7",
     "@types/request-promise": "^4.1.39",
     "coveralls": "^3.0.0",

packages/rest/src/internal-types.ts

@@ -11,7 +11,7 @@ export interface ParsedRequest extends ServerRequest {
   // see http://expressjs.com/en/4x/api.html#req.path
   path: string;
   // see http://expressjs.com/en/4x/api.html#req.query
-  query: {[key: string]: string};
+  query: {[key: string]: string | string[]};
   // see https://github.com/DefinitelyTyped/DefinitelyTyped/issues/15808
   url: string;
   pathname: string;

packages/rest/src/router/routing-table.ts

@@ -45,7 +45,13 @@ export function parseRequestUrl(request: ServerRequest): ParsedRequest {
   const parsedRequest = request as ParsedRequest;
   const parsedUrl = url.parse(parsedRequest.url, true);
   parsedRequest.path = parsedUrl.pathname || '/';
-  parsedRequest.query = parsedUrl.query;
+  // parsedUrl.query cannot be a string as it is parsed with
+  // parseQueryString = true
+  if (parsedUrl.query != null && typeof parsedUrl.query !== 'string') {
+    parsedRequest.query = parsedUrl.query;
+  } else {
+    parsedRequest.query = {};
+  }
   return parsedRequest;
 }