Ref T304, "no throw" JSON functions

src/blackmisc/containerbase.h

@@ -123,6 +123,7 @@ namespace BlackMisc
         }
 
         //! \copydoc BlackMisc::Mixin::JsonByMetaClass::convertFromJson
+        //! \throws CJsonException
         void convertFromJson(const QJsonObject &json)
         {
             derived().clear();
@@ -167,6 +168,25 @@ namespace BlackMisc
             return obj;
         }
 
+        //! Static version of convertFromJson
+        static Derived fromJsonNoThrow(const QString &jsonString, bool acceptCacheJson, bool &success, QString &errMsg)
+        {
+            success = false;
+            Derived obj;
+            try
+            {
+                if (jsonString.isEmpty()) { return obj; }
+                const QJsonObject jsonObj = acceptCacheJson ? Json::swiftDataObjectValue(jsonString) : Json::jsonObjectFromString(jsonString);
+                obj.convertFromJson(jsonObj);
+                success = true;
+            }
+            catch (const CJsonException &ex)
+            {
+                errMsg = ex.toString("JSON conversion");
+            }
+            return obj;
+        }
+
         //! Call convertFromJson, catch any CJsonException that is thrown and return it as CStatusMessage.
         CStatusMessage convertFromJsonNoThrow(const QJsonObject &json, const CLogCategoryList &categories, const QString &prefix); // implemented in statusmessage.h
 

src/blackmisc/json.cpp

@@ -393,7 +393,6 @@ namespace BlackMisc
             if (json.isEmpty()) { return QJsonObject();}
             const QJsonDocument jsonDoc(QJsonDocument::fromJson(json.toUtf8()));
             return acceptCacheFormat ? Json::unwrapCache(jsonDoc.object()) : jsonDoc.object();
-            // return acceptCacheFormat ? Json::swiftDataObjectValue(jsonDoc.object()) : jsonDoc.object();
         }
 
         QString stringFromJsonObject(const QJsonObject &jsonObject, QJsonDocument::JsonFormat format)

src/blackmisc/json.h

@@ -463,11 +463,32 @@ namespace BlackMisc
             static DerivedObj fromJson(const QString &jsonString, bool acceptCacheJson = false)
             {
                 DerivedObj obj;
+                if (jsonString.isEmpty()) { return obj; }
                 const QJsonObject jsonObj = acceptCacheJson ? Json::swiftDataObjectValue(jsonString) : Json::jsonObjectFromString(jsonString);
                 obj.convertFromJson(jsonObj);
                 return obj;
             }
 
+            //! Get object from JSON string
+            template<class DerivedObj = Derived>
+            static Derived fromJsonNoThrow(const QString &jsonString, bool acceptCacheJson, bool &success, QString &errMsg)
+            {
+                success = false;
+                Derived obj;
+                try
+                {
+                    if (jsonString.isEmpty()) { return obj; }
+                    const QJsonObject jsonObj = acceptCacheJson ? Json::swiftDataObjectValue(jsonString) : Json::jsonObjectFromString(jsonString);
+                    obj.convertFromJson(jsonObj);
+                    success = true;
+                }
+                catch (const CJsonException &ex)
+                {
+                    errMsg = ex.toString("JSON conversion");
+                }
+                return obj;
+            }
+
         private:
             const Derived *derived() const { return static_cast<const Derived *>(this); }
             Derived *derived() { return static_cast<Derived *>(this); }

src/blackmisc/jsonexception.cpp

@@ -26,12 +26,20 @@ namespace BlackMisc
 
     CStatusMessage CJsonException::toStatusMessage(const CLogCategoryList &categories, const QString &prefix) const
     {
-        return CStatusMessage(categories).validationError("%1: %2 in '%3'") << prefix << what() << getStackTrace();
+        return CStatusMessage(categories).validationError(toString(prefix));
+    }
+
+    QString CJsonException::toString(const QString &prefix) const
+    {
+        static const QString s("%1 in '%2'");
+        static const QString sp("%1: %2 in '%3'");
+        if (prefix.isEmpty()) { return s.arg(what()).arg(getStackTrace()); }
+        return sp.arg(prefix).arg(what()).arg(getStackTrace());
     }
 
     void CJsonException::toLogMessage(const CLogCategoryList &categories, const QString &prefix) const
     {
-        CLogMessage(categories).validationError("%1: %2 in '%3'") << prefix << what() << getStackTrace();
+        CLogMessage(categories).validationError(toString(prefix));
     }
 
     QString CJsonException::stackString()

src/blackmisc/jsonexception.h

@@ -36,6 +36,9 @@ namespace BlackMisc
         //! Get a status message representation.
         CStatusMessage toStatusMessage(const CLogCategoryList &categories, const QString &prefix) const;
 
+        //! As string info
+        QString toString(const QString &prefix) const;
+
         //! Write a message to the log.
         void toLogMessage(const CLogCategoryList &categories, const QString &prefix) const;
 

src/blackmisc/logcategory.h

@@ -208,6 +208,13 @@ namespace BlackMisc
             return cat;
         }
 
+        //! JSON and JSON conversions
+        static const CLogCategory &json()
+        {
+            static const CLogCategory cat { "swift.json" };
+            return cat;
+        }
+
         //! Startup of application
         static const CLogCategory &startup()
         {
@@ -271,7 +278,10 @@ namespace BlackMisc
                 dataInconsistency(),
                 download(),
                 driver(),
+                flightPlan(),
                 guiComponent(),
+                interpolator(),
+                json(),
                 mapping(),
                 matching(),
                 modelLoader(),

src/blackmisc/logpattern.cpp

@@ -33,6 +33,7 @@ namespace BlackMisc
             { "driver",                      exactMatch(CLogCategory::driver()) },
             { "flight plan",                 exactMatch(CLogCategory::flightPlan()) },
             { "interpolator",                exactMatch(CLogCategory::interpolator()) },
+            { "JSON (conversion)",           exactMatch(CLogCategory::json()) },
             { "model cache",                 exactMatch(CLogCategory::modelCache()) },
             { "model GUI",                   exactMatch(CLogCategory::modelGui()) },
             { "model loader",                exactMatch(CLogCategory::modelLoader()) },