Node JSON-Server returning MOCK post response

I'm trying to use https://www.npmjs.com/package/json-server as a mock backend, I'm able to match URLs for get, but how can i return some mock-response for POST calls.

Like for create user URL will be like

 URL - http://localhost:4000/user 
 Method - POST
 Request Data - {name:"abc", "address":"sample address"}

 expected response - 
 httpStats Code - 200, 
 Response Data - {"message":"user-created", "user-id":"sample-user-id"}

In Some Cases I also want to send custom http codes like 500,423,404,401 etc.. depending upon some data.

Biggest problem is that my code is not returning anything response for POST, its only inserting records in JSON

Solution

By default POST requests through json-server should give a 201 created response.

If you need custom response handling, you might need a middleware to get hold of req and res object.

Here I'm adding a middleware to intercept POST requests and send a custom response. You could tweak it to your specific case.

// Custom middleware to access POST methods.
// Can be customized for other HTTP method as well.
server.use((req, res, next) => {
  console.log("POST request listener");
  const body = req.body;
  console.log(body);
  if (req.method === "POST") {
    // If the method is a POST echo back the name from request body
    res.json({ message:"User created successfully", name: req.body.name});
  }else{
      //Not a post request. Let db.json handle it
      next();
  }  
});

Complete code (index.js)..

const jsonServer = require("json-server");
const server = jsonServer.create();
const router = jsonServer.router("db.json");
const middlewares = jsonServer.defaults();

server.use(jsonServer.bodyParser);
server.use(middlewares);


// Custom middleware to access POST methids.
// Can be customized for other HTTP method as well.
server.use((req, res, next) => {
  console.log("POST request listener");
  const body = req.body;
  console.log(body);
  if (req.method === "POST") {
    // If the method is a POST echo back the name from request body
    res.json({ message:"User created successfully", name: req.body.name});
  }else{
      //Not a post request. Let db.json handle it
      next();
  }  
});

server.use(router);

server.listen(3000, () => {
  console.log("JSON Server is running");
});

And you can start json-server using node index.js