fiber/middleware/keyauth/keyauth.go

141 lines
3.4 KiB
Go

// Special thanks to Echo: https://github.com/labstack/echo/blob/master/middleware/key_auth.go
package keyauth
import (
"errors"
"net/url"
"strings"
"github.com/gofiber/fiber/v3"
)
// The contextKey type is unexported to prevent collisions with context keys defined in
// other packages.
type contextKey int
// The keys for the values in context
const (
tokenKey contextKey = 0
)
// When there is no request of the key thrown ErrMissingOrMalformedAPIKey
var ErrMissingOrMalformedAPIKey = errors.New("missing or malformed API Key")
const (
query = "query"
form = "form"
param = "param"
cookie = "cookie"
)
// New creates a new middleware handler
func New(config ...Config) fiber.Handler {
// Init config
cfg := configDefault(config...)
// Initialize
parts := strings.Split(cfg.KeyLookup, ":")
extractor := keyFromHeader(parts[1], cfg.AuthScheme)
switch parts[0] {
case query:
extractor = keyFromQuery(parts[1])
case form:
extractor = keyFromForm(parts[1])
case param:
extractor = keyFromParam(parts[1])
case cookie:
extractor = keyFromCookie(parts[1])
}
// Return middleware handler
return func(c fiber.Ctx) error {
// Filter request to skip middleware
if cfg.Next != nil && cfg.Next(c) {
return c.Next()
}
// Extract and verify key
key, err := extractor(c)
if err != nil {
return cfg.ErrorHandler(c, err)
}
valid, err := cfg.Validator(c, key)
if err == nil && valid {
c.Locals(tokenKey, key)
return cfg.SuccessHandler(c)
}
return cfg.ErrorHandler(c, err)
}
}
// TokenFromContext returns the bearer token from the request context.
// returns an empty string if the token does not exist
func TokenFromContext(c fiber.Ctx) string {
token, ok := c.Locals(tokenKey).(string)
if !ok {
return ""
}
return token
}
// keyFromHeader returns a function that extracts api key from the request header.
func keyFromHeader(header, authScheme string) func(c fiber.Ctx) (string, error) {
return func(c fiber.Ctx) (string, error) {
auth := c.Get(header)
l := len(authScheme)
if len(auth) > 0 && l == 0 {
return auth, nil
}
if len(auth) > l+1 && auth[:l] == authScheme {
return auth[l+1:], nil
}
return "", ErrMissingOrMalformedAPIKey
}
}
// keyFromQuery returns a function that extracts api key from the query string.
func keyFromQuery(param string) func(c fiber.Ctx) (string, error) {
return func(c fiber.Ctx) (string, error) {
key := fiber.Query[string](c, param)
if key == "" {
return "", ErrMissingOrMalformedAPIKey
}
return key, nil
}
}
// keyFromForm returns a function that extracts api key from the form.
func keyFromForm(param string) func(c fiber.Ctx) (string, error) {
return func(c fiber.Ctx) (string, error) {
key := c.FormValue(param)
if key == "" {
return "", ErrMissingOrMalformedAPIKey
}
return key, nil
}
}
// keyFromParam returns a function that extracts api key from the url param string.
func keyFromParam(param string) func(c fiber.Ctx) (string, error) {
return func(c fiber.Ctx) (string, error) {
key, err := url.PathUnescape(c.Params(param))
if err != nil {
return "", ErrMissingOrMalformedAPIKey
}
return key, nil
}
}
// keyFromCookie returns a function that extracts api key from the named cookie.
func keyFromCookie(name string) func(c fiber.Ctx) (string, error) {
return func(c fiber.Ctx) (string, error) {
key := c.Cookies(name)
if key == "" {
return "", ErrMissingOrMalformedAPIKey
}
return key, nil
}
}