Add sdbusplus delegate

Add a DBus interface abstraction to facilitate
mocking and unit test.

Change-Id: I914cba7500d79bc4d3022cb12e4c02adf6a78c19
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>

1 files changed, 86 insertions, 0 deletions

diff --git a/src/sdbusplus.hpp b/src/sdbusplus.hpp
new file mode 100644
index 0000000..7dbf44d
--- /dev/null
+++ b/src/sdbusplus.hpp
@@ -0,0 +1,86 @@
+#pragma once
+
+#include <sdbusplus/bus.hpp>
+#include <sdbusplus/message.hpp>
+#include <sdbusplus/bus/match.hpp>
+
+namespace phosphor
+{
+namespace dbus
+{
+namespace monitoring
+{
+
+/** @class SDBusPlus
+ *  @brief DBus access delegate implementation for sdbusplus.
+ */
+class SDBusPlus
+{
+    private:
+        static auto& getBus()
+        {
+            static auto bus = sdbusplus::bus::new_default();
+            return bus;
+        }
+
+        static auto& getWatches()
+        {
+            static std::vector<sdbusplus::bus::match::match> watches;
+            return watches;
+        }
+
+    public:
+        /** @brief Invoke a method. */
+        template <typename ...Args>
+        static auto callMethod(
+            const std::string& busName,
+            const std::string& path,
+            const std::string& interface,
+            const std::string& method,
+            Args&& ... args)
+        {
+            auto reqMsg = getBus().new_method_call(
+                              busName.c_str(),
+                              path.c_str(),
+                              interface.c_str(),
+                              method.c_str());
+            reqMsg.append(std::forward<Args>(args)...);
+            return getBus().call(reqMsg);
+        }
+
+        /** @brief Invoke a method and read the response. */
+        template <typename Ret, typename ...Args>
+        static auto callMethodAndRead(
+            const std::string& busName,
+            const std::string& path,
+            const std::string& interface,
+            const std::string& method,
+            Args&& ... args)
+        {
+            Ret resp;
+            sdbusplus::message::message respMsg =
+                callMethod<Args...>(
+                    busName,
+                    path,
+                    interface,
+                    method,
+                    std::forward<Args>(args)...);
+            respMsg.read(resp);
+            return resp;
+        }
+
+        /** @brief Register a DBus signal callback. */
+        static auto addMatch(
+            const std::string& match,
+            const sdbusplus::bus::match::match::callback_t& callback)
+        {
+            getWatches().emplace_back(
+                    getBus(),
+                    match,
+                    callback);
+        }
+};
+
+} // namespace monitoring
+} // namespace dbus
+} // namespace phosphor