Intercept parameters from http redirects (#2111)

util/request/intercept.go

@@ -0,0 +1,28 @@
+package request
+
+import (
+	"fmt"
+	"net/http"
+)
+
+type InterceptResult = func() (string, error)
+
+// InterceptRedirect captures a redirect url parameter
+func InterceptRedirect(param string, stop bool) (func(req *http.Request, via []*http.Request) error, InterceptResult) {
+	var val string
+	return func(req *http.Request, via []*http.Request) error {
+			if val == "" {
+				if val = req.URL.Query().Get(param); val != "" && stop {
+					return http.ErrUseLastResponse
+				}
+			}
+			return nil
+		},
+		func() (string, error) {
+			var err error
+			if val == "" {
+				err = fmt.Errorf("%s not found", param)
+			}
+			return val, err
+		}
+}

vehicle/nissan/identity.go

@@ -36,7 +36,6 @@ func (v *Identity) Login(user, password string) error {
 
 	var nToken Token
 	var realm string
-	var resp *http.Response
 	var code string
 
 	if err == nil {
@@ -95,20 +94,14 @@ func (v *Identity) Login(user, password string) error {
 		})
 
 		if err == nil {
-			v.CheckRedirect = func(req *http.Request, via []*http.Request) error { return http.ErrUseLastResponse }
-			resp, err = v.Do(req)
-			v.CheckRedirect = nil
+			var param request.InterceptResult
+			v.Client.CheckRedirect, param = request.InterceptRedirect("code", true)
 
-			if err == nil {
-				resp.Body.Close()
-
-				var location *url.URL
-				if location, err = url.Parse(resp.Header.Get("Location")); err == nil {
-					if code = location.Query().Get("code"); code == "" {
-						err = fmt.Errorf("missing auth code: %v", location)
-					}
-				}
+			if _, err = v.Do(req); err == nil {
+				code, err = param()
 			}
+
+			v.CheckRedirect = nil
 		}
 	}