proposal: encoding/json: require all fields

[jaykam]

Hi @rsc @adg

I've noticed that encoding/json doesn't raise an error if any field is not present in the body payload.

Example:

type DecodeRequest struct{
     ID int   `json:"id"`
     Name string `json:"name"`
}

func DecodeRequest(g *gin.Context) error{
       var decodeRq DecodeRequest
       dec := json.NewDecoder(g.Request.Body)   //Body payload : {"id" : 123}
       dec.DisallowUnknownFields()
       err := dec.Decode(&decodeRq)
       fmt.Println(err) -> nil
       }

Ideally, this function should give an error like missingfield name.

DisallowUnknownFields just take care of extra fields but not the missing field.

Golang version: 1.15.6

Let me know if I've missed anything to fix it?

[seankhliao]

see also #17163 #19858

[jaykam]

@seankhliao Thanks for the reply.
I see that this proposal is already on hold.
When can we expect this feature in the next release?

Thanks

[mvdan]

Yes, this is a duplicate of #19858. We can't provide timeline estimates, sorry - taking a look at all JSON proposals is a big chunk of ongoing work.