[express]: adding generics for query type (#43434)

* add-generics-to-query-type: adding generics for query type in express core

* add-generics-to-query-type: fixing test case + lint

* add-generics-to-query-type: updating the default query type for express

* add-generics-to-query-type: fixing failed test cases

* add-generics-to-query-type: fixing express-paginate-tests

Co-authored-by: Puneet Arora <parora@atlassian.com>

types/easy-session/easy-session-tests.ts

@@ -49,7 +49,7 @@ app.get('/hasrole', function (req, res, next) {
 });
 
 app.post('/setrole', function (req, res, next) {
-    req.session.setRole(req.query.role);
+    req.session.setRole(req.query.role as string);
     res.send(200);
 });
 
@@ -59,4 +59,4 @@ app.get('/getrole', function (req, res, next) {
 
 app.use(easySession.isLoggedIn());
 app.use(easySession.isFresh());
-app.use(easySession.checkRole('user'));
+app.use(easySession.checkRole('user'));

types/express-paginate/express-paginate-tests.ts

@@ -12,7 +12,7 @@ app.get('/users', async (req, res, next) => {
     return findAndCountAll({limit: req.query.limit, offset: req.skip})
         .then(results => {
             const itemCount = results.count;
-            const pageCount = Math.ceil(results.count / req.query.limit);
+            const pageCount = Math.ceil(results.count / parseInt(req.query.limit as string, 10));
             res.render('users/all_users', {
                 users: results.rows,
                 pageCount,
@@ -20,7 +20,7 @@ app.get('/users', async (req, res, next) => {
                 currentPageHref: paginate.href(req)(false, req.params),
                 // Instead of exposing this to the html template, we'll test this here and pass a static number
                 hasNextPages: paginate.hasNextPages(req)(pageCount),
-                pages: paginate.getArrayPages(req)(3, pageCount, req.query.page)
+                pages: paginate.getArrayPages(req)(3, pageCount, parseInt(req.query.page as string, 10))
             });
         }).catch(next);
 });

types/express-serve-static-core/express-serve-static-core-tests.ts

@@ -32,6 +32,17 @@ app.get<{ foo: string }>('/:foo', req => {
 // Params cannot be a custom type that does not conform to constraint
 app.get<{ foo: number }>('/:foo', () => {}); // $ExpectError
 
+// Query can be a custom type
+app.get<{}, any, any, {q: string}>('/:foo', req => {
+    req.query.q; // $ExpectType string
+    req.query.a; // $ExpectError
+});
+
+// Query will be defaulted to Query type
+app.get('/:foo', req => {
+    req.query; // $ExpectType Query
+});
+
 // Default types
 app.post("/", (req, res) => {
     req.params[0]; // $ExpectType string

types/express-serve-static-core/index.d.ts

@@ -40,26 +40,30 @@ export interface ParamsDictionary { [key: string]: string; }
 export type ParamsArray = string[];
 export type Params = ParamsDictionary | ParamsArray;
 
-export interface RequestHandler<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any> {
+// Return type of qs.parse, the default query parser (https://expressjs.com/en/api.html#app-settings-property).
+export interface Query { [key: string]: string | string[] | Query | Query[]; }
+
+export interface RequestHandler<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any, ReqQuery = Query> {
     // tslint:disable-next-line callable-types (This is extended from and can't extend from a type alias in ts<2.2
-    (req: Request<P, ResBody, ReqBody>, res: Response<ResBody>, next: NextFunction): any;
+    (req: Request<P, ResBody, ReqBody, ReqQuery>, res: Response<ResBody>, next: NextFunction): any;
 }
 
-export type ErrorRequestHandler<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any> = (err: any, req: Request<P, ResBody, ReqBody>, res: Response<ResBody>, next: NextFunction) => any;
+export type ErrorRequestHandler<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any, ReqQuery = Query> =
+    (err: any, req: Request<P, ResBody, ReqBody, ReqQuery>, res: Response<ResBody>, next: NextFunction) => any;
 
 export type PathParams = string | RegExp | Array<string | RegExp>;
 
-export type RequestHandlerParams<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any>
-    = RequestHandler<P, ResBody, ReqBody>
-    | ErrorRequestHandler<P, ResBody, ReqBody>
+export type RequestHandlerParams<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any, ReqQuery = Query>
+    = RequestHandler<P, ResBody, ReqBody, ReqQuery>
+    | ErrorRequestHandler<P, ResBody, ReqBody, ReqQuery>
     | Array<RequestHandler<P>
     | ErrorRequestHandler<P>>;
 
 export interface IRouterMatcher<T, Method extends 'all' | 'get' | 'post' | 'put' | 'delete' | 'patch' | 'options' | 'head' = any> {
     // tslint:disable-next-line no-unnecessary-generics (This generic is meant to be passed explicitly.)
-    <P extends Params = ParamsDictionary, ResBody = any, ReqBody = any>(path: PathParams, ...handlers: Array<RequestHandler<P, ResBody, ReqBody>>): T;
+    <P extends Params = ParamsDictionary, ResBody = any, ReqBody = any, ReqQuery = Query>(path: PathParams, ...handlers: Array<RequestHandler<P, ResBody, ReqBody, ReqQuery>>): T;
     // tslint:disable-next-line no-unnecessary-generics (This generic is meant to be passed explicitly.)
-    <P extends Params = ParamsDictionary, ResBody = any, ReqBody = any>(path: PathParams, ...handlers: Array<RequestHandlerParams<P, ResBody, ReqBody>>): T;
+    <P extends Params = ParamsDictionary, ResBody = any, ReqBody = any, ReqQuery = Query>(path: PathParams, ...handlers: Array<RequestHandlerParams<P, ResBody, ReqBody, ReqQuery>>): T;
     (path: PathParams, subApplication: Application): T;
 }
 
@@ -209,7 +213,7 @@ export type Errback = (err: Error) => void;
  *     app.get<ParamsArray>(/user\/(.*)/, (req, res) => res.send(req.params[0]));
  *     app.get<ParamsArray>('/user/*', (req, res) => res.send(req.params[0]));
  */
-export interface Request<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any> extends http.IncomingMessage, Express.Request {
+export interface Request<P extends Params = ParamsDictionary, ResBody = any, ReqBody = any, ReqQuery = Query> extends http.IncomingMessage, Express.Request {
     /**
      * Return request header.
      *
@@ -463,7 +467,7 @@ export interface Request<P extends Params = ParamsDictionary, ResBody = any, Req
 
     params: P;
 
-    query: any;
+    query: ReqQuery;
 
     route: any;
 

types/express/express-tests.ts

@@ -168,6 +168,17 @@ namespace express_tests {
     // Params cannot be a custom type that does not conform to constraint
     router.get<{ foo: number }>('/:foo', () => {}); // $ExpectError
 
+    // Query can be a custom type
+    router.get('/:foo', (req: express.Request<{}, any, any , {q: string}>) => {
+        req.query.q; // $ExpectType string
+        req.query.a; // $ExpectError
+    });
+
+    // Query will be defaulted to any
+    router.get('/:foo', (req: express.Request<{}>) => {
+        req.query; // $ExpectType Query
+    });
+
     // Response will default to any type
     router.get("/", (req: Request, res: express.Response) => {
         res.json({});

types/express/index.d.ts

@@ -104,7 +104,7 @@ declare namespace e {
     interface IRouterMatcher<T> extends core.IRouterMatcher<T> { }
     interface MediaType extends core.MediaType { }
     interface NextFunction extends core.NextFunction { }
-    interface Request<P extends core.Params = core.ParamsDictionary> extends core.Request<P> { }
+    interface Request<P extends core.Params = core.ParamsDictionary, ResBody = any, ReqBody = any, ReqQuery = core.Query> extends core.Request<P, ResBody, ReqBody, ReqQuery> { }
     interface RequestHandler<P extends core.Params = core.ParamsDictionary> extends core.RequestHandler<P> { }
     interface RequestParamHandler extends core.RequestParamHandler { }
     export interface Response<ResBody = any> extends core.Response<ResBody> { }

types/ghost-storage-base/ghost-storage-base-tests.ts

@@ -41,5 +41,5 @@ storage.getSanitizedFileName('IMAGE.jpg'); // $ExpectType string
 
 storage.exists('tmp/123456.jpg', '/'); // $ExpectType Promise<boolean>
 storage.save(image, '/'); // $ExpectType Promise<string>
-storage.serve(); // $ExpectType (req: Request<ParamsDictionary>, res: Response<any>, next: NextFunction) => void
+storage.serve(); // $ExpectType (req: Request<ParamsDictionary, any, any, Query>, res: Response<any>, next: NextFunction) => void
 storage.delete('tmp/123456.jpg', '/'); // $ExpectType Promise<boolean>

types/passport-jwt/passport-jwt-tests.ts

@@ -33,7 +33,7 @@ opts.jwtFromRequest = ExtractJwt.fromUrlQueryParameter('param_name');
 opts.jwtFromRequest = ExtractJwt.fromAuthHeaderWithScheme('param_name');
 opts.jwtFromRequest = ExtractJwt.fromExtractors([ExtractJwt.fromHeader('x-api-key'), ExtractJwt.fromBodyField('field_name'), ExtractJwt.fromUrlQueryParameter('param_name')]);
 opts.jwtFromRequest = ExtractJwt.fromAuthHeaderAsBearerToken();
-opts.jwtFromRequest = (req: Request) => { return req.query.token; };
+opts.jwtFromRequest = (req: Request) => { return req.query.token as string; };
 opts.secretOrKey = new Buffer('secret');
 
 declare function findUser(condition: {id: string}, callback: (error: any, user :any) => void): void;