如何在node.js（express）中全局设置内容类型

Question

I might be wrong but I wasn't able to find this in any documentation. I am trying to set content type globally for any response and did it like:

    // Set content type GLOBALLY for any response.
  app.use(function (req, res, next) {
    res.contentType('application/json');
    next();
  });

before defining my routes.

 // Users REST methods.
  app.post('/api/v1/login', auth.willAuthenticateLocal, users.login);
  app.get('/api/v1/logout', auth.isAuthenticated, users.logout);
  app.get('/api/v1/users/:username', auth.isAuthenticated, users.get);

For some reason this doesn't work. Do you know what I am doing wrong? Setting it in each method separately, works but I want it globally...

Answer 1

Try this for Express 4.0 :

// this middleware will be executed for every request to the app
app.use(function (req, res, next) {
  res.header("Content-Type",'application/json');
  next();
});

Answer 2

Found the issue: this setting has to be put BEFORE:

app.use(app.router)

so the final code is:

// Set content type GLOBALLY for any response.
app.use(function (req, res, next) {
  res.contentType('application/json');
  next();
});

// routes should be at the last
app.use(app.router)