Cache distro_series so it's not fetched multiple times

src/source_package_publishing_history.cpp

@@ -27,6 +27,7 @@ source_package_publishing_history::source_package_publishing_history()
       lp(nullptr),
       distro_series([this]() -> std::optional<class distro_series> {
           if (distro_series_link.empty()) return std::nullopt;
+          if (_distro_series) return _distro_series;
 
           auto response = lp ? lp->api_get(distro_series_link) : std::nullopt;
           if (!response) return std::nullopt;
@@ -36,6 +37,7 @@ source_package_publishing_history::source_package_publishing_history()
 
           if (ds) {
               ds->set_lp(lp);
+              _distro_series = ds;
               return ds;
           }
 

src/source_package_publishing_history.h

@@ -57,6 +57,7 @@ public:
 
 private:
     launchpad* lp;
+    std::optional<class distro_series> _distro_series = std::nullopt;
 };
 
 #endif // SOURCE_PACKAGE_PUBLISHING_HISTORY