const express = require('express');

const TestObj = require('@example/test');

function basicTaint() {

const app = express();

app.use((req, res, next) => {

req.tainted = source();

req.safe = 'safe';

next();

});

app.get('/', (req, res) => {

sink(req.tainted); // NOT OK

sink(req.safe); // OK

});

}

function basicApiGraph() {

const app = express();

app.use((req, res, next) => {

req.obj = new TestObj();

next();

});

app.get('/', (req, res) => {

sink(req.obj.getSource()); // NOT OK

req.obj.getSink(source()); // NOT OK

});

}

function noTaint() {

const app = express();

function middleware(req, res, next) {

req.tainted = source();

req.safe = 'safe';

next();

}

app.get('/unsafe', middleware, (req, res) => {

sink(req.tainted); // NOT OK

sink(req.safe); // OK

});

app.get('/safe', (req, res) => {

sink(req.tainted); // OK - not preceded by middleware

sink(req.safe); // OK

});

}

function looseApiGraphStep() {

const app = express();

function middleware(req, res, next) {

req.obj = new TestObj();

next();

}

app.get('/unsafe', middleware, (req, res) => {

sink(req.obj.getSource()); // NOT OK

});

app.get('/safe', (req, res) => {

sink(req.obj.getSource()); // NOT OK - we allow API graph steps within the same app

});

}

function chainMiddlewares() {

const app = express();

function step1(req, res, next) {

req.taint = source();

next();

}

function step2(req, res, next) {

req.locals.alsoTaint = req.taint;

next();

}

app.get('/', step1, step2, (req, res) => {

sink(req.taint); // NOT OK

sink(req.locals.alsoTaint); // NOT OK

});

}

function routerEscapesIntoParameter() {

const app = express();

function setupMiddlewares(router) {

router.use((req, res, next) => {

req.taint = source();

next();

});

}

app.get('/before', (req, res) => {

sink(req.taint); // OK

});

setupMiddlewares(app);

app.get('/after', (req, res) => {

sink(req.taint); // NOT OK

});

}

function routerReturned() {

const app = express();

function makeMiddlewares() {

let router = new express.Router();

router.use((req, res, next) => {

req.taint = source();

next();

});

return router;

}

app.get('/before', (req, res) => {

sink(req.taint); // OK

});

app.use(makeMiddlewares());

app.get('/after', (req, res) => {

sink(req.taint); // NOT OK

});

}

function routerCaptured() {

const app = express();

function addMiddlewares() {

app.use((req, res, next) => {

req.taint = source();

next();

});

}

app.get('/before', (req, res) => {

sink(req.taint); // OK

});

addMiddlewares();

app.get('/after', (req, res) => {

sink(req.taint); // NOT OK

});

}

function withPath() {

const app = express();

app.use('/foo', (req, res, next) => {

req.taint = source();

next();

});

app.get('/foo', (req, res) => {

sink(req.taint); // NOT OK

});

app.get('/bar', (req, res) => {

sink(req.taint); // OK

});

}

function withNestedPath() {

const app = express();

app.use('/foo/bar', (req, res, next) => {

req.taint = source();

next();

});

function makeRouter() {

const router = express.Router();

router.get('/bar', (req, res) => {

sink(req.taint); // NOT OK

})

router.get('/baz', (req, res) => {

sink(req.taint); // OK

})

return router;

}

app.get('/foo', makeRouter());

app.get('/bar', (req, res) => {

sink(req.taint); // OK

});

}

function withHttpMethods() {

const app = express();

app.get('/foo', (req, res, next) => {

req.taintGet = source();

next();

});

app.post('/foo', (req, res, next) => {

req.taintPost = source();

next();

});

app.all('/foo', (req, res, next) => {

req.taintAll = source();

next();

});

app.get('/foo/a', (req, res) => {

sink(req.taintGet); // NOT OK

sink(req.taintPost); // OK - not tainted for GET requests

sink(req.taintAll); // NOT OK

});

app.post('/foo/b', (req, res) => {

sink(req.taintGet); // OK - not tainted for POST requests

sink(req.taintPost); // NOT OK

sink(req.taintAll); // NOT OK

});

app.all('/foo/c', (req, res) => {

sink(req.taintGet); // NOT OK

sink(req.taintPost); // NOT OK

sink(req.taintAll); // NOT OK

});

}

function withChaining() {

const app = express();

app.use('/', (req, res) => {

sink(req.taint); // OK

});

function middleware() {

return express.Router()

.use((req, res, next) => {

req.taint = source();

next();

})

.use(blah());

}

app.use(middleware());

app.use('/', (req, res) => {

sink(req.taint); // NOT OK

});

}

function withClass() {

class App {

constructor(router) {

this.router = router;

this.earlyRoutes();

this.addMiddleware();

this.lateRoutes();

}

earlyRoutes() {

this.router.get('/', (req, res) => {

sink(req.taint); // OK

})

}

addMiddleware() {

this.router.use((req, res, next) => {

req.taint = source();

next();

})

}

lateRoutes() {

this.router.get('/', (req, res) => {

sink(req.taint); // NOT OK

})

}

}

let app = new App(express());

}

function withArray() {

const app = express();

app.get('/before', (req, res) => {

sink(req.taint); // OK

});

app.use([

(req, res, next) => {

sink(req.taint); // OK

next();

},

(req, res, next) => {

req.taint = source();

next();

},

(req, res, next) => {

sink(req.taint); // NOT OK

next();

}

]);

app.get('/after', (req, res) => {

sink(req.taint); // NOT OK

});

}

function withForLoop() {

const app = express();

let middlewares = [

(req, res, next) => {

sink(req.taint); // OK

next();

},

(req, res, next) => {

req.taint = source();

next();

},

(req, res, next) => {

sink(req.taint); // NOT OK

next();

}

];

app.get('/before', (req, res) => {

sink(req.taint); // OK

});

for (let route of middlewares) {

app.use(route);

}

app.get('/after', (req, res) => {

sink(req.taint); // NOT OK

});

}

function routeHandlersInProps() {

let routes = require('./routes');

const app = express();

app.use(routes.first);

app.get('/', routes.second);

}