bug: required errors use golang name instead of field name

[davidalpert]

Given a type with required fields:

type ProductQuery struct {
	CreatedAt time.Time `in:"form=created_at;required"`
	Color     string    `in:"form=colour,color"`
	IsSoldout bool      `in:"form=is_soldout"`
	SortBy    []string  `in:"form=sort_by"`
	SortDesc  []bool    `in:"form=sort_desc"`
	Pagination
	Authorization
}

When I make a request to an endpoint parsing this type with httpin
Then I expect the error to be

invalid field "created_at": missing required field

Currently the error is

invalid field "CreatedAt": missing required field

which can be misleading to clients, since submitting a request with a CreatedAt property is not guaranteed to bind.

[ggicci]

Thanks @davidalpert

This was an intended design. In httpin we allow applying multiple directives to a field. And at the same time for a directive, it also can have multiple args. For instance:

Token string `in:"form=access_token,token;header=x-api-token;required"`

IMO, it's too complex to name the field by concating the directives together to indicate which field had an error.

I agree with the point that currently the error message is missleading. But compared with the solution #9 had provided I propose if we could add more "contexts" to InvalidFieldError to make it more clear.

For example, just expose the Directives:

type InvalidFieldError struct {
	// Field is the name of the field.
	Field string `json:"field"`

	// Source is the directive which causes the error.
	// e.g. form, header, required, etc.
	Source string `json:"source"`

	// Value is the input data.
	Value interface{} `json:"value"`

	// internalError is the underlying error thrown by the directive executor.
	internalError error  `json:"-"`
	ErrorMessage  string `json:"error"`

	// The directives bound to this field. <------ here :)
	Directives []*Directive `json:"directives"`
}

The advantage here is we can access the directives data in a structured way. Which should be easier for someone if they want to tweak InvalidFieldError before sending to the client.

[ggicci]

It's not covenient to tweak the error before sending to the client in the default middleware handler httpin.NewInput @ggicci

[ggicci]

Hi @davidalpert , now the bound Directives has been exposed to InvalidationFieldError, and overriding the default error handler has also been supported.

Closed and feel free to reopen it :)