Auth Provider (#1309)

* auth provider mock interface

* Auth Provider Options

* Implement API Server Auth Package

* Add weh utils

* Add Login URL

* Auth Provider Options

* Add auth provider scope and setting token in cookie

* Remove auth_login_url flag

Co-authored-by: Asim Aslam <asim@aslam.me>
Co-authored-by: Ben Toogood <ben@micro.mu>

util/http/http.go

@@ -1,12 +1,47 @@
 package http
 
 import (
+	"encoding/json"
+	"fmt"
+	"log"
 	"net/http"
 
 	"github.com/micro/go-micro/v2/client/selector"
 	"github.com/micro/go-micro/v2/registry"
 )
 
+// Write sets the status and body on a http ResponseWriter
+func Write(w http.ResponseWriter, contentType string, status int, body string) {
+	w.Header().Set("Content-Length", fmt.Sprintf("%v", len(body)))
+	w.Header().Set("Content-Type", contentType)
+	w.WriteHeader(status)
+	fmt.Fprintf(w, `%v`, body)
+}
+
+// WriteBadRequestError sets a 400 status code
+func WriteBadRequestError(w http.ResponseWriter, err error) {
+	rawBody, err := json.Marshal(map[string]string{
+		"error": err.Error(),
+	})
+	if err != nil {
+		WriteInternalServerError(w, err)
+		return
+	}
+	Write(w, "application/json", 400, string(rawBody))
+}
+
+// WriteInternalServerError sets a 500 status code
+func WriteInternalServerError(w http.ResponseWriter, err error) {
+	rawBody, err := json.Marshal(map[string]string{
+		"error": err.Error(),
+	})
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	Write(w, "application/json", 500, string(rawBody))
+}
+
 func NewRoundTripper(opts ...Option) http.RoundTripper {
 	options := Options{
 		Registry: registry.DefaultRegistry,