Autopatch and Readonly Fields?

[Fishwaldo]

I'm having a look at the new Autopatch functionality.

I send something like this:
[{"op":"replace","path":"/description","value":"MouthPieceApp123"}]

In my GET Operation, I return a model with a number of fields Marked ReadOnly, but description is not:

type appGetResponse struct {
	ID          int                  `doc:"ID of the Application" readOnly:"true" json:"id"`
	Name        string               `doc:"Name of the Application" pattern:"^[a-zA-Z0-9_]+$" minLength:"3" maxLength:"32" json:"name"`
	Description string               `doc:"Description of the Application" pattern:"^[a-zA-Z0-9_]+$" minLength:"0" maxLength:"255" json:"description,omitempty"`
	Filters     []appFiltersResponse `doc:"Filters of the Application" json:"filters,omitempty" readOnly:"true"`
	Groups      []appGroupResponse   `doc:"Groups of the Application" json:"groups,omitempty" readOnly:"true"`
}

and my PUT operation input model is:

type appPutRequest struct {
	ID   int `doc:"ID of the Application" readOnly:"true" path:"id"`
	Body struct {
		appGetResponse
	}
}

Before hitting the actual PUT Operation, Huma rejects a json-patch operation with errors such as:

{
  "title": "Unprocessable Entity",
  "status": 422,
  "detail": "Error while processing input parameters",
  "errors": [
    {
      "message": "Additional property id is not allowed",
      "location": "body",
      "value": 1
    },
    {
      "message": "Additional property groups is not allowed",
      "location": "body",
      "value": [
        {
          "Description": "Default MouthPiece App Group",
          "ID": 8589934593,
          "Name": "MouthPiece"
        }
      ]
    }
  ]
}

if I change the Body struct for my appPutRequest struct to just the mutable fields, I still get errors about additional fields - those copied from the internal GET request.

I'm guessing readonly fields should be dropped from the final request sent internally to the PUT handler, but looking over the patch code, I see we basically just copy the result of the GET operation into the json-patch library without any filtering at all. (

huma/patch.go

Line 225 in 1519e49

patched, err = patch.Apply(origWriter.Body.Bytes())

) so I'm guessing this usecase isn't handled?

[Fishwaldo]

Also - regarding the comparision between the original and patched inputs here:

huma/patch.go

Line 243 in 1519e49

if bytes.Compare(patched, origWriter.Body.Bytes()) == 0 {

if I read json-patch documentation, we should use:

jsonpatch.Equal(document1, document2)

[danielgtaylor]

Take a look at #63 which is related to this problem and would enable you to drop read-only fields on the input side.

Perhaps the better solution is to have the auto-patch code detect and remove read-only fields. I'd be open to a PR that implements that!