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The right way to know which line of json is failing to unmarshal? – Getting Assist

I’m engaged on an app that makes use of go to parse a json file for settings. I get the error proven under, nevertheless it’s not telling me what line within the json file is inflicting the problem. How do I see this?

panic: json: can not unmarshal string into Go worth of kind map[string]*json.RawMessage

You possibly can examine your Go code to see the place you’ve a discipline of kind map[string]*json.RawMessage after which examine your JSON file to see if it’s a string as a substitute.

I don’t have entry to the code. I hoped there was a method to activate extra detailed logs like in Rust

I’m not conscious of any method to try this in Go.

Might you paste your JSON into an internet JSON parser and see what the offending line is that method? Additionally you might organize a fast take a look at utilizing the playground and attempt to debug it that method. For instance, modify this playground hyperlink to have your precise JSON:

func important() {
	// Change this together with your JSON
	byt := []byte(`{ "value1": "take a look at", "value2": }`)
	var dat map[string]*json.RawMessage
	if err := json.Unmarshal(byt, &dat); err != nil {

The output from that’s at the least extra descriptive than what your executable is supplying you with:

panic: invalid character '}' on the lookout for starting of worth

goroutine 1 [running]:
	/tmp/sandbox266866198/prog.go:13 +0xe7

Program exited.

You possibly can additionally attempt the process outlined right here together with that go playground hyperlink to get extra data:

Although as soon as once more, an internet JSON parser ought to work positive to offer you an in depth error message.

That helps if the JSON is invalid, however if you happen to put a JSON string worth the place an object is anticipated (e.g. {"key": "string"} vs {"key": {"subkey": "string"}}), I don’t assume this may assist until you’ve a JSON schema definition.

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Ah good name – I incorrectly assumed it was invalid JSON as a result of map[string]*json.RawMessage is fairly versatile (it will possibly deal with each the examples you talked about simply positive). However you’re completely proper – it’s legitimate JSON to have solely an array as top-level textual content:

And in that case, map[string] would break.


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