Is there a purpose in sending back a value within the request handler of an express route?

Here's a straightforward query: What impact does returning a value in the express route request handler have?


I've observed various approaches when handling request responses:

route.get('/something', (req, res) => {
  // blah blah

  if (/* something */) {
    return res.send('something'); // return on the same line
  }

  return res.send('something else');
});

Some developers perform an early return after sending a response:

route.get('/something', (req, res) => {
  if (/* something */) {
    res.send('something');
    return; // return after
  }

  res.send('something else');
  return;
});

Is there any distinguishable difference? Does the returned value serve any purpose?

Answer №1

Is there a difference in Express when returning a value from the request handler?

Actually, no. Express doesn't care about the return value from your route handler.

For example, using:

return res.send(...);

is equivalent to:

res.send(...);
return;

In Express, both of these statements have the same effect. The return statement is only used for flow control (to exit the function) and not because it actually returns a value.

I personally prefer the second approach as it removes any confusion that could arise from seeing a return statement in this context.

Answer №2

In addition to what was mentioned earlier, including a return value can be beneficial for unit testing purposes. By returning a value that can be verified within a test framework, one can eliminate the need to rely on tools such as supertest for conducting basic tests on a module or class.

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