Returning validation error

Getting Help
1 
func foo(w http.ResponseWriter, r *http.Request, status int, data interface{}){
	if err := encoder.Encode(w, r, data); err != nil {
		http.Error(//error here)
		}
}
			
foo(w, r, http.StatusBadRequest, fmt.Errorf("Invalid message")

this returns {} in an error condition instead of writing the actual error(Invalid message), what I am missing here. I want function to write the given error message.

Go PlayGround

2

I’m not sure if it’s relevant but you’re missing ) here in the end of line.

3

Just in case you aren’t already: make sure you’re calling return after calling http.Error else your program will continue.

4

that’s just copy pasta thing.

5

Also, it seems like the function doesn’t return anything?

6

it doesn’t have to as it is just wrapper to write response.

7

What is encoder.Encode? It doesn’t appear to be in the standard library and it’s hard to know how to help fix the code without knowing what the function is doing.

A playground link would be marvelous too, although I realize it’s not always that easy to yank something out of a large code base and get it running there.

8

I think your “//error here” comment is where the actual work should be done right? I would expect that line to be…

http.Error(w, err, 500)

Is that what your doing? If do, the response should have been written to the response writer’s “Write” method.

2 Likes
9

added the playground link above.

10

added the playground link with most of the code.

11

So I was stupid, I was passing an error such as errors.New(“error”), instead I need to pass errors.New(“error”).Error().

thanks Guys.

12

That just gives you the string “error” though, with a little bit of extra work (including an allocation?).

13

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