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javascriptnode.jshttphttpresponse

Under what conditions might res.status() or res.json() throw/raise an error

I have this generic function I have for a library:

const sendResponse = (res: Response, errorTrace: InspectedError) => {

  if (res.headersSent) {
    log.warning('Headers already sent for response. Error:', errorTrace);
  }

  try {
    res.status(500);  // this one
  } catch (err) {
    log.error(err);
  }

  try {
    res.json({      // this one
      foo: 'bar'
    });

  } catch (err) {
    log.error(err);
  }

};

I am curious what kinds of errors might be raised by res.status() and res.json() - is the best bet to look at the source or is there a better way to find out?

Solution

  • Some situations I can think of:

    1. res is invalid and either isn't an object or doesn't have a status or json method.
    2. res.json() can fail if you give it an invalid parameter or you give it an object that contains circular references (that can't be represented in JSON).