added filter by attribute to python api

LibCarla/source/carla/client/ActorAttribute.h

@@ -224,7 +224,6 @@ namespace client {
       return _attribute;
     }
 
-  protected:
     virtual const std::string &GetValue() const override {
       return _attribute.value;
     }

LibCarla/source/carla/client/BlueprintLibrary.cpp

@@ -33,6 +33,21 @@ namespace client {
     return SharedPtr<BlueprintLibrary>{new BlueprintLibrary(result)};
   }
 
+  SharedPtr<BlueprintLibrary> BlueprintLibrary::FilterByAttribute(
+      const std::string &name, const std::string& value) const {
+    map_type result;
+    for (auto &pair : _blueprints) {
+      if (!pair.second.ContainsAttribute(name))
+        continue;
+      const ActorAttribute &Attribute = pair.second.GetAttribute(name);
+      const std::string &AttributeValue = Attribute.GetValue();
+      if (value == AttributeValue) {
+        result.emplace(pair);
+      }
+    }
+    return SharedPtr<BlueprintLibrary>{new BlueprintLibrary(result)};
+  }
+
   BlueprintLibrary::const_pointer BlueprintLibrary::Find(const std::string &key) const {
     auto it = _blueprints.find(key);
     return it != _blueprints.end() ? &it->second : nullptr;

LibCarla/source/carla/client/BlueprintLibrary.h

@@ -43,6 +43,7 @@ namespace client {
     /// Filters a list of ActorBlueprint with id or tags matching
     /// @a wildcard_pattern.
     SharedPtr<BlueprintLibrary> Filter(const std::string &wildcard_pattern) const;
+    SharedPtr<BlueprintLibrary> FilterByAttribute(const std::string &name, const std::string& value) const;
 
     const_pointer Find(const std::string &key) const;
 

PythonAPI/carla/source/libcarla/Blueprint.cpp

@@ -172,6 +172,7 @@ void export_blueprint() {
       return self.at(key);
     }, (arg("id")))
     .def("filter", &cc::BlueprintLibrary::Filter, (arg("wildcard_pattern")))
+    .def("filter_by_attribute", &cc::BlueprintLibrary::FilterByAttribute, (arg("name"), arg("value")))
     .def("__getitem__", +[](const cc::BlueprintLibrary &self, size_t pos) -> cc::ActorBlueprint {
       return self.at(pos);
     })