dcdbpusher RestAPI: Add endpoints to (un)load plugins

common/src/RESTHttpsServer.cpp

@@ -308,6 +308,8 @@ std::string RESTHttpsServer::splitUri(const std::string& uri, queries_t& queries
     std::string path;
     std::string query;
 
+    ServerLOG(debug) << "Splitting URI " << uri;
+
     size_t pos = uri.find('?');
     path = uri.substr(0, pos);
     query = uri.substr(pos+1, uri.length());

dcdbpusher/Configuration.cpp

@@ -68,7 +68,7 @@ bool Configuration::readPlugins(PluginManager& pluginManager) {
 					}
 				}
 
-				if(!pluginManager.loadPlugin(pluginSettings, pluginName, pluginPath, pluginConfig)) {
+				if(!pluginManager.loadPlugin(pluginName, pluginPath, pluginConfig)) {
 				    LOG(error) << "Could not load plugin " << pluginName;
 				    pluginManager.unloadPlugin();
 				    return false;

dcdbpusher/PluginManager.cpp

@@ -13,12 +13,14 @@
 
 using namespace std;
 
+PluginManager::PluginManager(const pluginSettings_t& pluginSettings) :
+    _pluginSettings(pluginSettings) {}
+
 PluginManager::~PluginManager() {
     unloadPlugin();
 }
 
-bool PluginManager::loadPlugin(const pluginSettings_t& pluginSettings,
-                               const string& name,
+bool PluginManager::loadPlugin(const string& name,
                                const string& pluginPath,
                                const string& config) {
 
@@ -91,7 +93,7 @@ bool PluginManager::loadPlugin(const pluginSettings_t& pluginSettings,
 
     plugin.configurator = plugin.create();
     //set prefix to global prefix (may be overwritten)
-    plugin.configurator->setGlobalSettings(pluginSettings);
+    plugin.configurator->setGlobalSettings(_pluginSettings);
     //read in config
     if (!(plugin.configurator->readConfig(pluginConfig))) {
         LOG(error) << "Plugin " << plugin.id << " could not read configuration!";
@@ -124,6 +126,8 @@ void PluginManager::unloadPlugin(const string& id) {
                 g->stop();
             }
 
+            removeTopics(*it);
+
             if (it->configurator) {
                 it->destroy(it->configurator);
             }

dcdbpusher/PluginManager.h

@@ -37,8 +37,18 @@ using pusherPluginStorage_t = std::vector<pusherPlugin_t>;
 class PluginManager {
 
 public:
-    PluginManager() {};
 
+    /**
+     * @brief Constructor.
+     *
+     * @param pluginSettings Use this plugin settings as default when loading
+     *                       a new plugin.
+     */
+    PluginManager(const pluginSettings_t& pluginSettings);
+
+    /**
+     * @brief Destructor.
+     */
     virtual ~PluginManager();
 
     /**
@@ -52,8 +62,6 @@ public:
      *          loading the plugin still has to be initialized (initPlugin())
      *          before it can be started (startPlugin()).
      *
-     *
-     * @param pluginSettings Default settings for the plugin.
      * @param name           Identifying name (ID) of the new plugin.
      * @param pluginPath     Path where the plugin shared library is located. If
      *                       not specified we will search the default library
@@ -65,8 +73,7 @@ public:
      * @return True on success, false otherwise. In the latter case the plugin
      *         is not loaded.
      */
-    bool loadPlugin(const pluginSettings_t& pluginSettings,
-                    const std::string& name,
+    bool loadPlugin(const std::string& name,
                     const std::string& pluginPath = "",
                     const std::string& config = "");
 
@@ -171,6 +178,8 @@ private:
     void removeTopics(const pusherPlugin_t& p);
 
     pusherPluginStorage_t _plugins; /**< Storage to hold all loaded plugins */
+    pluginSettings_t _pluginSettings; /**< Default plugin settings to use when
+                                           loading a new plugin */
     logger_t lg;
 };
 

dcdbpusher/README.md

@@ -179,6 +179,44 @@ Tables with allowed ressources sorted by REST methods can be found below. A quer
   </tr>
 </table>
 
+<table>
+  <tr>
+    <td colspan="2"><b>PUT /load</b></td>
+    <td colspan="2">Load and intitialize a new plugin but do not start it. Use the /start request to kick off the plugin's data collection.</td>
+  </tr>
+  <tr>
+  	<td>plugin</td>
+  	<td>Plugin name.</td>
+  	<td>No</td>
+  	<td>Name of the new plugin. Is used to build the shared library file name which holds the plugin. Shared lib file name is of the form libdcdbplugin_PLUGINNAME.so (or .dylib for Apple).</td>
+  </tr>
+  <tr>
+  	<td>path</td>
+  	<td>A file path.</td>
+  	<td>Yes</td>
+  	<td>Path to where the shared library for the plugin is located. If not specified the default library directories (urs/lib and friends) are searched.</td>
+  </tr>
+  <tr>
+  	<td>config</td>
+  	<td>A file path including file name.</td>
+  	<td>Yes</td>
+  	<td>Path and name of the plugin configuration file. If not specified we will search for "./PLUGINNAME.conf".</td>
+  </tr>
+</table>
+
+<table>
+  <tr>
+    <td colspan="2"><b>PUT /unload</b></td>
+    <td colspan="2">Unload a plugin, removing it completely from dcdbpusher. To use the plugin again one has to /load it first.</td>
+  </tr>
+  <tr>
+  	<td>plugin</td>
+  	<td>All plugin names.</td>
+  	<td>No</td>
+  	<td>Specify the plugin.</td>
+  </tr>
+</table>
+
 <table>
   <tr>
     <td colspan="2"><b>PUT /start</b></td>

dcdbpusher/RestAPI.cpp

@@ -33,6 +33,8 @@ RestAPI::RestAPI(serverSettings_t settings,
     addEndpoint("/sensors", {http::verb::get, stdBind(GET_sensors)});
     addEndpoint("/average", {http::verb::get, stdBind(GET_average)});
 
+    addEndpoint("/load",    {http::verb::put, stdBind(PUT_load)});
+    addEndpoint("/unload",  {http::verb::put, stdBind(PUT_unload)});
     addEndpoint("/start",   {http::verb::put, stdBind(PUT_start)});
     addEndpoint("/stop",    {http::verb::put, stdBind(PUT_stop)});
     addEndpoint("/reload",  {http::verb::put, stdBind(PUT_reload)});
@@ -184,6 +186,66 @@ void RestAPI::GET_average(endpointArgs) {
     }
 }
 
+void RestAPI::PUT_load(endpointArgs) {
+    const std::string plugin = getQuery("plugin", queries);
+    const std::string path   = getQuery("path", queries);
+    const std::string config = getQuery("config", queries);
+
+    if (!hasPlugin(plugin, res)) {
+        return;
+    }
+
+    //before modifying the plugin we need to ensure that we have exclusive access
+    //therefore pause the only other concurrent user (MQTTPusher)
+    if (!_mqttPusher->halt()) {
+        res.body() = "Could not reload plugin (Timeout while waiting).\n";
+        res.result(http::status::internal_server_error);
+        return;
+    }
+
+    if(_pluginManager->loadPlugin(plugin, path, config)) {
+        res.body() = "Plugin " + plugin + " successfully loaded!\n";
+        res.result(http::status::ok);
+
+        _pluginManager->initPlugin(_io, plugin);
+    } else {
+        res.body() = "Failed to load plugin " + plugin + "!\n";
+        res.result(http::status::internal_server_error);
+    }
+
+    //continue MQTTPusher
+    _mqttPusher->cont();
+
+    //Updating the SensorNavigator on plugin reloads, if analytics plugins are currently running
+    if (_manager!=NULL && _manager->getPlugins().size()>0) {
+        QueryEngine &qEngine = QueryEngine::getInstance();
+        std::shared_ptr <SensorNavigator> navigator = std::make_shared<SensorNavigator>();
+        std::vector<std::string> names, topics;
+        for (const auto &p : _pluginManager->getPlugins())
+            for (const auto &g : p.configurator->getSensorGroups())
+                for (const auto &s : g->getSensors()) {
+                    names.push_back(s->getName());
+                    topics.push_back(s->getMqtt());
+                }
+        navigator->buildTree(qEngine.getSensorHierarchy(), &names, &topics);
+        qEngine.setNavigator(navigator);
+        qEngine.triggerUpdate();
+    }
+}
+
+void RestAPI::PUT_unload(endpointArgs) {
+    const std::string plugin = getQuery("plugin", queries);
+
+    if (!hasPlugin(plugin, res)) {
+        return;
+    }
+
+    _pluginManager->unloadPlugin(plugin);
+    res.body() = "Plugin " + plugin + " unloaded.\n";
+    res.result(http::status::ok);
+    return;
+}
+
 void RestAPI::PUT_start(endpointArgs) {
     const std::string plugin = getQuery("plugin", queries);
 

dcdbpusher/RestAPI.h

@@ -39,7 +39,12 @@ public:
                                   "                           Average of last sensor readings from the last\n"
                                   "                           [interval] seconds or of all cached readings if no\n"
                                   "                           interval is given.\n"
-                                  " -PUT: /start?plugin       Start the sensors of the plugin.\n"
+                                  " -PUT: /load?plugin;[path];[config]\n"
+                                  "                           Load a new plugin. Optionally specify path to the\n"
+                                  "                           shared library and/or the config file for the "
+                                  "                           plugin.\n"
+                                  "       /unload?plugin      Unload a plugin."
+                                  "       /start?plugin       Start the sensors of the plugin.\n"
                                   "       /stop?plugin        Stop the sensors of the plugin.\n"
                                   "       /reload?plugin      Reload the plugin configuration.\n"
                                   "\n";
@@ -102,6 +107,36 @@ private:
 
 /******************************************************************************/
 
+    /**
+     * PUT "/load"
+     *
+     * @brief Load and initialize a plugin but do not start it yet.
+     *
+     * Queries  | key     | possible values      | explanation
+     * -------------------------------------------------------------------------
+     * Required | plugin  | name of the new      | specify the plugin
+     *          |         | plugin               |
+     * Optional | path    | file path            | specify a file path where to
+     *          |         |                      | search for the shared lib.
+     *          |         |                      | Defaults to (usr/lib etc.)
+     *          | config  | file path + name     | specify the config file for
+     *          |         |                      | the plugin. Defaults to
+     *          |         |                      | ./PLUGINNAME.conf
+     */
+    void PUT_load(endpointArgs);
+
+    /**
+     * PUT "/unload"
+     *
+     * @brief Unload a plugin.
+     *
+     * Queries  | key     | possible values      | explanation
+     * -------------------------------------------------------------------------
+     * Required | plugin  | all plugin names     | specify the plugin
+     * Optional |  -      |        -             |      -
+     */
+    void PUT_unload(endpointArgs);
+
     /**
      * PUT "/start"
      *

dcdbpusher/dcdbpusher.cpp

@@ -255,7 +255,7 @@ int main(int argc, char** argv) {
 
 	LOG(info) << "Logging setup complete";
 
-	_pluginManager = new PluginManager();
+	_pluginManager = new PluginManager(pluginSettings);
 	//Read in rest of configuration. Also creates all sensors
 	if(!_configuration->readPlugins(*_pluginManager)) {
 		LOG(fatal) << "Failed to read configuration!";