Allow errors returned by queries to be wrapped with method name information

[Hades32]

What do you want to change?

Free unicorns! And...

Currently, when I use a bunch of query methods (like q.SelectUnicorns()) and then just do the usual if err!=nil{return err }, then I'll have a hard time figuring out which of those caused the SQL error.

Therefore, I typically do

err := q.SelectUnicorns()`
if err!= nil{
 return fmt.Errorf("SelectUnicorns %w", err)
}

It would be nice if there was a feature toggle to enable this wrapping right within the generated code.

What database engines need to be changed?

No response

What programming language backends need to be changed?

Go

[jgustie]

It would be nice to have the option to enable error wrapping under gen.go in the config; tracking down errors within complex services (especially something like a "no rows" error which otherwise has no other context) can be difficult.

I was able to hack together my own solution by enabling gen.go.emit_interface and using GoWrap to create a decorator with a template similar to this:

...

//{{$decorator}} implements{{.Interface.Type}} and wraps errors with the associated query name.
type{{$decorator}} struct{{{.Interface.Type}} }

{{range $method := .Interface.Methods}}
func (w *{{$decorator}}){{$method.Declaration}}{
	{{$method.ResultsNames}} = w.{{$.Interface.Name}}.{{$method.Call}}
	if err != nil{
		err = &SqlcError{QueryName: "{{$method.Name}}", wrapped: err}
	}
	return
}
{{end}}