From f3d59556efd7e4930eb2633277ebe9f969d5cd0a Mon Sep 17 00:00:00 2001
From: Weiyi Wang <wwylele@gmail.com>
Date: Mon, 17 Sep 2018 14:28:58 -0400
Subject: [PATCH] web_backend: protect jwt cache with a mutex

---
 src/web_service/web_backend.cpp | 2 ++
 src/web_service/web_backend.h   | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/web_service/web_backend.cpp b/src/web_service/web_backend.cpp
index e935d8b15..3c5d278e8 100644
--- a/src/web_service/web_backend.cpp
+++ b/src/web_service/web_backend.cpp
@@ -24,6 +24,7 @@ Client::JWTCache Client::jwt_cache{};
 
 Client::Client(const std::string& host, const std::string& username, const std::string& token)
     : host(host), username(username), token(token) {
+    std::lock_guard<std::mutex> lock(jwt_cache.mutex);
     if (username == jwt_cache.username && token == jwt_cache.token) {
         jwt = jwt_cache.jwt;
     }
@@ -116,6 +117,7 @@ void Client::UpdateJWT() {
         if (result.result_code != Common::WebResult::Code::Success) {
             LOG_ERROR(WebService, "UpdateJWT failed");
         } else {
+            std::lock_guard<std::mutex> lock(jwt_cache.mutex);
             jwt_cache.username = username;
             jwt_cache.token = token;
             jwt_cache.jwt = jwt = result.returned_data;
diff --git a/src/web_service/web_backend.h b/src/web_service/web_backend.h
index be115f96e..955b91c7a 100644
--- a/src/web_service/web_backend.h
+++ b/src/web_service/web_backend.h
@@ -5,7 +5,7 @@
 #pragma once
 
 #include <functional>
-#include <future>
+#include <mutex>
 #include <string>
 #include <tuple>
 #include <httplib.h>
@@ -81,6 +81,7 @@ private:
     std::unique_ptr<httplib::Client> cli;
 
     struct JWTCache {
+        std::mutex mutex;
         std::string username;
         std::string token;
         std::string jwt;