Upd07

• IovDto corrected (when some parameters are null).
• CrestBaseResponse corrected (when page is null).
• ctests corrected.
• CMakeLists.txt.athena is updated.

src/CrestModel.cxx

@@ -79,7 +79,15 @@
         crestResponse.format = j.value("format", "");
 
         // Check for the presence of "page" key and create an optional
-        crestResponse.page = j.contains("page") ? std::make_optional(RespPage::from_json(j["page"])) : std::nullopt;
+        if (j.contains("page")){
+	  if (!j["page"].is_null()){
+	    crestResponse.page = std::make_optional((RespPage::from_json(j["page"])));
+	  }
+	}
+	else {
+	  crestResponse.page = std::nullopt;
+	}
+	
         // Check for the presence of "filter" key and create an optional
         crestResponse.filter = j.contains("filter") ? std::make_optional(GenericMap::from_json(j["filter"])) : std::nullopt;
 
@@ -365,6 +373,7 @@
         }
         return tagSet;
     }
+
     json IovDto::to_json() const
     {
         return {
@@ -373,13 +382,37 @@
             {"insertionTime", insertionTime},
             {"payloadHash", payloadHash}};
     }
+
     IovDto IovDto::from_json(const json &j)
     {
         IovDto iov;
         iov.tagName = j.value("tagName", "");
-            iov.since = j.value<long_t>("since", 0);
-        iov.insertionTime = j.value("insertionTime", "");
-        iov.payloadHash = j.value("payloadHash", "");
+        iov.since = j.value<long_t>("since", 0);
+	
+	if (j.contains("insertionTime")){
+	  if (!j["insertionTime"].is_null()){
+	    iov.insertionTime = j["insertionTime"];
+	  }
+	  else {
+	    iov.insertionTime = "";
+	  }
+	}
+	else {
+	  iov.insertionTime = "";
+	}
+	
+	if (j.contains("payloadHash")){
+	  if (!j["payloadHash"].is_null()){
+	    iov.payloadHash = j["payloadHash"];
+	  }
+	  else {
+	    iov.payloadHash = "";
+	  }
+	}
+	else {
+	  iov.payloadHash = "";
+	}	
+	
         return iov;
     }