Move getResourceList to Util class

Allows a future commit to separate memory and process
functionality.

Tested: Top commit tested.
Change-Id: Icd3d26c054adf0477c938a7795a42b102cc05098
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/redfish-core/include/utils/collection.hpp b/redfish-core/include/utils/collection.hpp
new file mode 100644
index 0000000..31d5da1
--- /dev/null
+++ b/redfish-core/include/utils/collection.hpp
@@ -0,0 +1,54 @@
+#pragma once
+
+#include <boost/container/flat_map.hpp>
+
+#include <string>
+#include <vector>
+
+namespace redfish
+{
+namespace collection_util
+{
+
+inline void getResourceList(std::shared_ptr<AsyncResp> aResp,
+                            const std::string& subclass,
+                            const std::vector<const char*>& collectionName)
+{
+    BMCWEB_LOG_DEBUG << "Get available system cpu/mem resources.";
+    crow::connections::systemBus->async_method_call(
+        [subclass, aResp{std::move(aResp)}](
+            const boost::system::error_code ec,
+            const boost::container::flat_map<
+                std::string, boost::container::flat_map<
+                                 std::string, std::vector<std::string>>>&
+                subtree) {
+            if (ec)
+            {
+                BMCWEB_LOG_DEBUG << "DBUS response error";
+                messages::internalError(aResp->res);
+                return;
+            }
+            nlohmann::json& members = aResp->res.jsonValue["Members"];
+            members = nlohmann::json::array();
+
+            for (const auto& object : subtree)
+            {
+                auto iter = object.first.rfind("/");
+                if ((iter != std::string::npos) && (iter < object.first.size()))
+                {
+                    members.push_back(
+                        {{"@odata.id", "/redfish/v1/Systems/system/" +
+                                           subclass + "/" +
+                                           object.first.substr(iter + 1)}});
+                }
+            }
+            aResp->res.jsonValue["Members@odata.count"] = members.size();
+        },
+        "xyz.openbmc_project.ObjectMapper",
+        "/xyz/openbmc_project/object_mapper",
+        "xyz.openbmc_project.ObjectMapper", "GetSubTree",
+        "/xyz/openbmc_project/inventory", 0, collectionName);
+}
+
+} // namespace collection_util
+} // namespace redfish