Create auth API & comment code

internal/web/api/api.go

@@ -0,0 +1,86 @@
+package api
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"github.com/gorilla/mux"
+	"net/http"
+	"strings"
+)
+
+func SetupAPI(router *mux.Router) {
+	router.NotFoundHandler = NotFoundHandler{}
+	router.MethodNotAllowedHandler = MethodNotAllowedHandler{}
+
+	router.Path("/auth/login").Methods("POST").HandlerFunc(apiHandleAuthLogin)
+	router.Path("/auth/register").Methods("POST").HandlerFunc(apiHandleAuthRegister)
+
+	bot := router.PathPrefix("/bot").Subrouter()
+	bot.Use(checkAuthMiddleware)
+
+	bot.Path("/test").HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+		writer.WriteHeader(200)
+
+		claims := request.Context().Value("claims").(jwtClaims)
+
+		writer.Write([]byte(`hello ` + claims.Username))
+	})
+}
+
+func checkAuthMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(res http.ResponseWriter, req *http.Request) {
+		token := req.Header.Get("Authorization")
+		tokenSplit := strings.Split(token, " ")
+
+		if token == "" || len(tokenSplit) < 2 {
+			writeJSONError(res, http.StatusUnauthorized, errors.New("bearer token required"))
+			return
+		}
+
+		token = tokenSplit[1]
+
+		claims, _, err := parseToken(token)
+		if err != nil {
+			writeJSONError(res, http.StatusUnauthorized, errors.New("invalid token"))
+			return
+		}
+
+		ctx := context.WithValue(req.Context(), "claims", *claims)
+
+		req = req.WithContext(ctx)
+
+		next.ServeHTTP(res, req)
+	})
+}
+
+func writeJSONError(res http.ResponseWriter, statusCode int, err error) {
+	res.Header().Set("Content-Type", "application/json")
+	res.WriteHeader(statusCode)
+
+	enc, _ := json.Marshal(struct {
+		Error     string `json:"error"`
+		ErrorCode int    `json:"error_code"`
+	}{
+		Error:     err.Error(),
+		ErrorCode: statusCode,
+	})
+
+	_, _ = res.Write(enc)
+}
+
+type NotFoundHandler struct{}
+
+func (NotFoundHandler) ServeHTTP(res http.ResponseWriter, req *http.Request) {
+	res.Header().Set("Content-Type", "application/json")
+	res.WriteHeader(http.StatusNotFound)
+	_, _ = res.Write([]byte(`{"error": "not_found","error_code":404}`))
+}
+
+type MethodNotAllowedHandler struct{}
+
+func (MethodNotAllowedHandler) ServeHTTP(res http.ResponseWriter, req *http.Request) {
+	res.Header().Set("Content-Type", "application/json")
+	res.WriteHeader(http.StatusMethodNotAllowed)
+	_, _ = res.Write([]byte(`{"error": "method_not_allowed","error_code":405}`))
+}