add CountProperty() to plugin APIs, throw is GetProperty doesn't find key

fairmq/Plugin.h

@@ -84,6 +84,7 @@ class Plugin
 
     // device config API
     // see <fairmq/PluginServices.h> for docs
+    auto PropertyExists(const std::string& key) -> int { return fPluginServices->PropertyExists(key); }
     template<typename T>
     auto SetProperty(const std::string& key, T val) -> void { fPluginServices->SetProperty(key, val); }
     template<typename T>

fairmq/PluginServices.h

@@ -165,6 +165,9 @@ class PluginServices
     auto UnsubscribeFromDeviceStateChange(const std::string& subscriber) -> void { fDevice->UnsubscribeFromStateChange(subscriber); }
 
     // Config API
+    struct PropertyNotFoundError : std::runtime_error { using std::runtime_error::runtime_error; };
+
+    auto PropertyExists(const std::string& key) const -> bool { return fConfig->Count(key) > 0; }
 
     /// @brief Set config property
     /// @param key
@@ -195,14 +198,24 @@ class PluginServices
     /// TODO Currently, if a non-existing key is requested and a default constructed object is returned.
     /// This behaviour will be changed in the future to throw an exception in that case to provide a proper sentinel.
     template<typename T>
-    auto GetProperty(const std::string& key) const -> T { return fConfig->GetValue<T>(key); }
+    auto GetProperty(const std::string& key) const -> T {
+        if (PropertyExists(key)) {
+            return fConfig->GetValue<T>(key);
+        }
+        throw PropertyNotFoundError(fair::mq::tools::ToString("Config has no key: ", key));
+    }
 
     /// @brief Read config property as string
     /// @param key
     /// @return config property value converted to string
     ///
     /// If a type is not supported, the user can provide support by overloading the ostream operator for this type
-    auto GetPropertyAsString(const std::string& key) const -> std::string { return fConfig->GetStringValue(key); }
+    auto GetPropertyAsString(const std::string& key) const -> std::string {
+        if (PropertyExists(key)) {
+            return fConfig->GetStringValue(key);
+        }
+        throw PropertyNotFoundError(fair::mq::tools::ToString("Config has no key: ", key));
+    }
 
     auto GetChannelInfo() const -> std::unordered_map<std::string, int> { return fConfig->GetChannelInfo(); }
 

fairmq/options/FairProgOptions.h

@@ -17,6 +17,7 @@
 
 #include "FairMQLogger.h"
 #include "FairProgOptionsHelper.h"
+#include <fairmq/Tools.h>
 
 #include <boost/program_options.hpp>
 #include <boost/filesystem.hpp>
@@ -26,6 +27,7 @@
 #include <iostream>
 #include <fstream>
 #include <mutex>
+#include <exception>
 
 namespace po = boost::program_options;
 namespace fs = boost::filesystem;
@@ -61,21 +63,14 @@ class FairProgOptions
         std::unique_lock<std::mutex> lock(fConfigMutex);
 
         T val = T();
-        try
+
+        if (fVarMap.count(key))
         {
-            if (fVarMap.count(key))
-            {
-                val = fVarMap[key].as<T>();
-            }
-            else
-            {
-                LOG(error) << "Config has no key: " << key;
-            }
+            val = fVarMap[key].as<T>();
         }
-        catch (std::exception& e)
+        else
         {
-            LOG(error) << "Exception thrown for the key '" << key << "'";
-            LOG(error) << e.what();
+            LOG(warn) << "Config has no key: " << key << ". Returning default constructed object.";
         }
 
         return val;

fairmq/plugins/DDS/DDS.cxx

@@ -182,8 +182,14 @@ auto DDS::FillChannelContainers() -> void
         }
 
         // save properties that will have multiple values arriving (with only some of them to be used)
-        vector<string> iValues = GetProperty<vector<string>>("dds-i");
-        vector<string> inValues = GetProperty<vector<string>>("dds-i-n");
+        vector<string> iValues;
+        if (PropertyExists("dds-i")) {
+            iValues = GetProperty<vector<string>>("dds-i");
+        }
+        vector<string> inValues;
+        if (PropertyExists("dds-i-n")) {
+            inValues = GetProperty<vector<string>>("dds-i-n");
+        }
 
         for (const auto& vi : iValues) {
             size_t pos = vi.find(":");

fairmq/shmem/FairMQSocketSHM.cxx

@@ -292,6 +292,8 @@ int64_t FairMQSocketSHM::Send(vector<FairMQMessagePtr>& msgVec, const int flags)
             return nbytes;
         }
     }
+
+    return -1;
 }
 
 
@@ -365,6 +367,8 @@ int64_t FairMQSocketSHM::Receive(vector<FairMQMessagePtr>& msgVec, const int fla
             return nbytes;
         }
     }
+
+    return -1;
 }
 
 void FairMQSocketSHM::Close()