nodejs unhandled promise rejection when app.post

Question

When my angular frontend sends post request

order(market: string, price: string, side: string, size: string): Observable<any> {
        var payload = { market: market, order: { price: price, side: side, size: size } };
        return this.http.post<any>('http://localhost:3000' + "/orders", payload))
            .pipe(
                tap((res: any) => {
                   console.log(res);
                }),
                retry(3), // retry a failed request up to 3 times
                catchError(this.handleError) // then handle the error
            );
    }

my nodejs server receives it

app.post('/orders', (req, res) => {
    console.log(req.body) 
    // more code

    setTimeout(function () {
        axios.post('https://test.com/api/orders', payload, { headers: headers })
            .then((response) => { 
                if (response.status === 201) {
                    res.sendStatus(201);                    
                } else {
                    res.sendStatus(400);  
                }           
            })
    }, 500);    
});

I added setTimeout because without it I'm getting Error: Request failed with status code 400.

As a result, I can post an order to test.com/api/orders, but getting promise rejection.

(node:9220) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag --unhandled-rejections=strict (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2) (node:9220) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Any enhancement i can make here?

Answer 1

Try moving the function content into a try block and catch the errors. I also recommend to use async await keywords.