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Vlad Tanasie
7,201 Pointsres.json is not a function
I keep getting this no matter what i do TypeError: res.json is not a function
2 Answers
Steven Parker
231,268 PointsFor more specific answers, always show your code (or provide a link to a repo or snapshot).
But as a generic hint, mostly likely "res" did not get set to an instance of the object that would have a "json" method. I'd guess it's probably either undefined or null at the point where this message is seen. Start by confirming that, and if my guess is right trace back to where "res" should have been assigned and look for the real issue there.
Joseph Butterfield
Full Stack JavaScript Techdegree Graduate 16,430 PointsI know this is almost a year later, but I had the same problem. I found the solution was that I posted my get function as
app.get('/greetings', (res, req) => {
res.json({greeting: "Hello World"})
});
My solution was swapping the res, and req parameters within the callback function. Not sure why that worked, and now I am curious, but it did. ¯_(ツ)_/¯ Solution being, write (req, res) => {}
Can anyone weigh in on why that works?
Steven Parker
231,268 PointsA response object (the 2nd argument) has a "json" method, but a request object (the first argument) does not.