json: Add constructor for loading a fan app's config file(s)
Create a constructor that takes a void function from a fan app that is
called to have that fan app load its config file(s) if the compatible
interface is found upon starting or after an intefacesAdded signal is
received. This will eventually replace the other constructor that's used
in a similar manner once all fan apps have been updated to use this
constructor.
Change-Id: I70a2d933b49f3c711a03cd2a8d555094e8449d17
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
diff --git a/json_config.hpp b/json_config.hpp
index 3fd53b1..ecd6353 100644
--- a/json_config.hpp
+++ b/json_config.hpp
@@ -36,6 +36,7 @@
constexpr auto confOverridePath = "/etc/phosphor-fan-presence";
constexpr auto confBasePath = "/usr/share/phosphor-fan-presence";
+constexpr auto confCompatServ = "xyz.openbmc_project.EntityManager";
constexpr auto confCompatIntf =
"xyz.openbmc_project.Configuration.IBMCompatibleSystem";
constexpr auto confCompatProp = "Names";
@@ -124,6 +125,76 @@
}
/**
+ * @brief Constructor
+ *
+ * Attempts to set the list of compatible values from the compatible
+ * interface and call the fan app's function to load its config file(s). If
+ * the compatible interface is not found, it subscribes to the
+ * interfacesAdded signal for that interface on the compatible service
+ * defined above.
+ *
+ * @param[in] func - Fan app function to call to load its config file(s)
+ */
+ JsonConfig(std::function<void()> func) : _loadFunc(func)
+ {
+ _match = std::make_unique<sdbusplus::server::match::match>(
+ util::SDBusPlus::getBus(),
+ sdbusplus::bus::match::rules::interfacesAdded() +
+ sdbusplus::bus::match::rules::sender(confCompatServ),
+ std::bind(&JsonConfig::compatIntfAdded, this,
+ std::placeholders::_1));
+ try
+ {
+ auto compatObjPaths = getCompatObjPaths();
+ if (!compatObjPaths.empty())
+ {
+ for (auto& path : compatObjPaths)
+ {
+ try
+ {
+ // Retrieve json config compatible relative path
+ // locations (last one found will be what's used if more
+ // than one dbus object implementing the comptaible
+ // interface exists).
+ _confCompatValues = util::SDBusPlus::getProperty<
+ std::vector<std::string>>(util::SDBusPlus::getBus(),
+ path, confCompatIntf,
+ confCompatProp);
+ }
+ catch (const util::DBusError&)
+ {
+ // Compatible property unavailable on this dbus object
+ // path's compatible interface, ignore
+ }
+ }
+ _loadFunc();
+ _match.reset();
+ }
+ else
+ {
+ // Check if required config(s) are found not needing the
+ // compatible interface, otherwise this is intended to catch the
+ // exception thrown by the getConfFile function when the
+ // required config file was not found. This would then result in
+ // waiting for the compatible interfacesAdded signal
+ try
+ {
+ _loadFunc();
+ _match.reset();
+ }
+ catch (const std::runtime_error&)
+ {
+ // Wait for compatible interfacesAdded signal
+ }
+ }
+ }
+ catch (const std::runtime_error&)
+ {
+ // Wait for compatible interfacesAdded signal
+ }
+ }
+
+ /**
* @brief The interfacesAdded callback function that looks for
* the IBMCompatibleSystem interface. If it finds it,
* it uses the Names property in the interface to find
@@ -177,6 +248,37 @@
}
/**
+ * @brief InterfacesAdded callback function for the compatible interface.
+ *
+ * @param[in] msg - The D-Bus message contents
+ *
+ * If the compatible interface is found, it uses the compatible property on
+ * the interface to set the list of compatible values to be used when
+ * attempting to get a configuration file. Once the list of compatible
+ * values has been updated, it calls the load function.
+ */
+ void compatIntfAdded(sdbusplus::message::message& msg)
+ {
+ sdbusplus::message::object_path op;
+ std::map<std::string,
+ std::map<std::string, std::variant<std::vector<std::string>>>>
+ intfProps;
+
+ msg.read(op, intfProps);
+
+ if (intfProps.find(confCompatIntf) == intfProps.end())
+ {
+ return;
+ }
+
+ const auto& props = intfProps.at(confCompatIntf);
+ // Only one dbus object with the compatible interface is used at a time
+ _confCompatValues =
+ std::get<std::vector<std::string>>(props.at(confCompatProp));
+ _loadFunc();
+ }
+
+ /**
* Get the json configuration file. The first location found to contain
* the json config file for the given fan application is used from the
* following locations in order.
@@ -336,6 +438,9 @@
*/
ConfFileReadyFunc _readyFunc;
+ /* Load function to call for a fan app to load its config file(s). */
+ std::function<void()> _loadFunc;
+
/**
* @brief The JSON config file
*/