In Express or connect with Node.js, is there a way to call another route internally?

Question

So, I have the setup like this (in Express):

app.get(\'/mycall1\', function(req,res) { res.send(\'Good\'); });
app.get(\'/mycall2\', function(req,res) { res.         


        

Answer 1

Like many things in javascript your original goal can be accomplished with sneakiness. We can overwrite the res.send function so that it doesn't call res.end; this will allow res.send to be called multiple times without issue. Note that this is an ugly, sneaky approach - not recommended, but potentially useful:

app.get('myAggregate', (req, res) => {
  // Overwrite `res.send` so it tolerates multiple calls:
  let restoreSend = res.send;
  res.send = () => { /* do nothing */ };

  // Call mycall1
  req.method = 'GET';
  req.url = '/mycall1';
  app.handle(req, res, () => {});

  // Call mycall2
  req.method = 'GET';
  req.url = '/mycall2';
  app.handle(req, res, () => {});

  // Restore `res.send` to its normal functionality
  res.send = restoreSend;

  // Finally, call `res.send` in conclusion of calling both mycall1 and mycall2
  res.send('Good AND Good2!');

});

Answer 2

No, this is not possible without rewriting or refactoring your code. The reason is that res.send actually calls res.end after it is done writing. That ends the response and nothing more can be written.

As you hinted to, you can achieve the desired effect by refactoring the code so that both /mycall1 and /mycall2 call separate functions internally, and /myAggregate calls both the functions.

In these functions, you would have to use res.write to prevent ending the response. The handlers for /mycall1, /mycall2, and /myAggregate would each have to call res.end separately to actually end the response.