closures.go

package csrf

import "errors"

// This is just an example on how to reduce redundant code in Go
// Original file: https://github.com/gofiber/csrf/blob/dde96da6711a2cc01709a66730c2e16328b22047/main.go

// csrfFromExtractor returns a function can be used to bind to a parameter name to extract a csrf token from a Ctx.
func csrfFromExtractor(errMessage string, extractor func(c *fiber.Ctx, param string) string) func(string) func(c *fiber.Ctx) (string, error) {
	return func(param string) func(c *fiber.Ctx) (string, error) {
		return func(c *fiber.Ctx) (string, error) {
			token := extractor(c, param)
			if token == "" {
				return "", errors.New("missing csrf token in " + errMessage)
			}
			return token, nil
		}
	}
}

var (
	// csrfFromQuery returns a function that extracts token from the query string.
	csrfFromQuery = csrfFromExtractor("query", (*fiber.Ctx).Query)
	// csrfFromHeader returns a function that extracts token from the request header.
	csrfFromHeader = csrfFromExtractor("header", (*fiber.Ctx).Get)
	// csrfFromParam returns a function that extracts token from the url parameters.
	csrfFromParam = csrfFromExtractor("url parameter", (*fiber.Ctx).Params)
	// csrfFromParam returns a function that extracts token from the form values.
	csrfFromForm = csrfFromExtractor("form parameter", (*fiber.Ctx).FormValue)
)