add new function getBoatDataValues to api for easier access

lib/api/GwApi.h

@@ -5,9 +5,16 @@
 #include "NMEA0183Msg.h"
 #include "GWConfig.h"
 #include "GwBoatData.h"
+#include <map>
+#include <vector>
 //API to be used for additional tasks
 class GwApi{
     public:
+        typedef std::map<String,double> ValueMap;
+        typedef std::vector<String> StringList;
+        /**
+         * thread safe methods - can directly be called from a user task
+         */
         virtual GwRequestQueue *getQueue()=0;
         virtual void sendN2kMessage(const tN2kMsg &msg, bool convert=true)=0;
         /**
@@ -16,10 +23,27 @@ class GwApi{
         virtual void sendNMEA0183Message(const tNMEA0183Msg &msg, int sourceId,bool convert=true)=0;
         virtual void sendNMEA0183Message(const tNMEA0183Msg &msg, bool convert=true)=0;
         virtual int getSourceId()=0;
+        /**
+         * the returned config data must only be read in a user task
+         * writing to it is not thread safe and could lead to crashes
+         */
         virtual GwConfigHandler *getConfig()=0;
         virtual GwLog *getLogger()=0;
-        virtual GwBoatData *getBoatData()=0;
         virtual const char* getTalkerId()=0;
+        /**
+         * get a set of boat data values by their names
+         * the returned map will have the keys being the strings in the names list
+         * the values are the boat data values converted to double
+         * invalid values are not returned in the map
+         * this method is thread safe and can directly be used from a user task
+         */
+        virtual ValueMap getBoatDataValues(StringList)=0;
+        /**
+         * not thread safe methods
+         * accessing boat data must only be executed from within the main thread
+         * you need to use the request pattern as shown in GwExampleTask.cpp
+         */
+        virtual GwBoatData *getBoatData()=0;
         virtual ~GwApi(){}
 };
 #ifndef DECLARE_USERTASK

lib/boatData/GwBoatData.cpp

@@ -329,6 +329,17 @@ String GwBoatData::toString(){
     }
     return rt;
 }
+bool GwBoatData::isValid(String name){
+    auto it=values.find(name);
+    if (it == values.end()) return false;
+    return it->second->isValid();
+}
+double GwBoatData::getDoubleValue(String name,double defaultv){
+    auto it=values.find(name);
+    if (it == values.end()) return defaultv;
+    if (! it->second->isValid()) return defaultv;
+    return it->second->getDoubleValue();
+}
 double formatCourse(double cv)
 {
     double rt = cv * 180.0 / M_PI;

lib/boatData/GwBoatData.h

@@ -69,7 +69,9 @@ class GwBoatItemBase{
         virtual size_t getJsonSize();
         virtual int getLastSource(){return lastUpdateSource;}
         virtual void refresh(unsigned long ts=0){uls(ts);}
+        virtual double getDoubleValue()=0;
         String getName(){return name;}
+        String getFormat(){return format;}
 };
 class GwBoatData;
 template<class T> class GwBoatItem : public GwBoatItemBase{
@@ -88,6 +90,7 @@ template<class T> class GwBoatItem : public GwBoatItemBase{
             if (! isValid(millis())) return defaultv;
             return data;
         }
+        virtual double getDoubleValue(){return (double)data;}
         virtual void fillString();
         virtual void toJsonDoc(GwJsonDocument *doc, unsigned long minTime);
         virtual int getLastSource(){return lastUpdateSource;}
@@ -120,6 +123,7 @@ class GwSatInfoList{
             if (idx >= 0 && idx < sats.size()) return &sats.at(idx);
             return NULL;
         }
+        operator double(){ return getNumSats();}
 };
 
 class GwBoatDataSatList : public GwBoatItem<GwSatInfoList>
@@ -136,6 +140,9 @@ public:
         if (! isValid()) return 0;
         return data.getNumSats();
     }
+    virtual double getDoubleValue(){
+        return (double)(data.getNumSats());
+    }
 
 };
 
@@ -199,6 +206,8 @@ class GwBoatData{
         template<class T> GwBoatItem<T> *getOrCreate(T initial,GwBoatItemNameProvider *provider);
         template<class T> bool update(T value,int source,GwBoatItemNameProvider *provider);
         template<class T> T getDataWithDefault(T defaultv, GwBoatItemNameProvider *provider);
+        bool isValid(String name);
+        double getDoubleValue(String name,double defaultv);
         String toJson() const;
         String toString();
 };

lib/exampletask/GwExampleTask.cpp

@@ -3,6 +3,7 @@
 #ifdef BOARD_TEST
 #include "GwExampleTask.h"
 #include "GwApi.h"
+#include <vector>
 
 /**
  * an init function that ist being called before other initializations from the core
@@ -48,7 +49,11 @@ void exampleTask(GwApi *api){
     //initialization goes here
     //------
     bool hasPosition=false;
+    bool hasPosition2=false;
     LOG_DEBUG(GwLog::DEBUG,"example switch ist %s",exampleSwitch?"true":"false");
+    GwApi::StringList itemNames;
+    itemNames.push_back(F("Latitude"));
+    itemNames.push_back(F("Longitude"));
     while(true){
         delay(1000);
         /*
@@ -89,6 +94,42 @@ void exampleTask(GwApi *api){
 
         }
         r->unref(); //delete the request
+
+        /** second example with string based functions to access boatData
+            uses STL vector and map - but does not need any request handling
+            this uses a reasonable amount of mmeory on the stack:
+            up to 2x the size of the list of names and 2x the size of the returned map
+            the default stack size of 2000 will not fit.
+            So be sure to use DECLARA_USERTASK_PARAM(taskFuntion,stackSize) and provide
+            a reasonable stack size (e.g. 4000 in this example).
+            Finally it only makes sense to use one of the versions - either with the request
+            or with the ValueMap approach.
+            The request access to boatData gives you more options on how to access the data
+            and ueses less ressources and runtime but this one is maybe easier to understand and implement
+        **/
+        //fetch the current values of the items that we have in itemNames
+        GwApi::ValueMap boatItems=api->getBoatDataValues(itemNames);
+        //get the values out of the map
+        //the returned item is a map iterator
+        auto longitude=boatItems.find(itemNames[1]);
+        auto latitude=boatItems.find(itemNames[0]);
+        //check if the iterators are valid (i.e. the values we requested have been found in boatData)
+        if (longitude != boatItems.end() && latitude != boatItems.end()){
+            //both values are there - so we have a valid position
+            if (! hasPosition2){
+                //access to the values via iterator->second (iterator->first would be the name)
+                if (exampleSwitch) LOG_DEBUG(GwLog::LOG,"(2)position availale lat=%f, lon=%f",
+                    latitude->second,longitude->second);
+                hasPosition2=true;
+            }
+        }
+        else{
+            if (hasPosition2){
+                if (exampleSwitch) LOG_DEBUG(GwLog::LOG,"(2)position lost");
+                hasPosition2=false;
+            }
+        }
+
     }
     vTaskDelete(NULL);
     

lib/exampletask/GwExampleTask.h

@@ -27,10 +27,11 @@ void exampleTask(GwApi *param);
 void exampleInit(GwApi *param);
 //make the task known to the core
 //the task function should not return (unless you delete the task - see example code)
-DECLARE_USERTASK(exampleTask)
-//if your task needs more stack then the default 2000 bytes, replace the DECLARE_USERTASK
-//with: DECLARE_USERTASK_PARAM(exampleTask,2500);
-//this will give you 2500 bytes of stack
+//we create our task with a stack size of 4000 bytes
+DECLARE_USERTASK_PARAM(exampleTask,4000)
+//if your task is happy with the default 2000 bytes of stack, replace the DECLARE_USERTASK_PARAM
+//with: DECLARE_USERTASK(exampleTask);
+
 
 //let the core call an init function before the 
 //N2K Stuff and the communication is set up

lib/usercode/GwUserCode.cpp

@@ -95,6 +95,10 @@ public:
     virtual const char* getTalkerId(){
         return api->getTalkerId();
     }
+    virtual ValueMap getBoatDataValues(StringList names){
+        GWSYNCHRONIZED(mainLock);
+        return api->getBoatDataValues(names);
+    }
     virtual ~TaskApi(){};
 };
 

src/main.cpp

@@ -339,6 +339,15 @@ public:
   virtual GwLog* getLogger(){
     return &logger;
   }
+  virtual GwApi::ValueMap getBoatDataValues(GwApi::StringList names){
+    std::map<String,double> rt;
+    for (auto it=names.begin();it!= names.end();it++){
+      if (boatData.isValid(*it)){
+        rt[*it]=boatData.getDoubleValue(*it,0);
+      }
+    }
+    return rt;
+  }
   virtual GwBoatData *getBoatData(){
     return &boatData;
   }
@@ -357,8 +366,8 @@ bool delayedRestart(){
     vTaskDelete(NULL);
   },"reset",1000,&logger,0,NULL) == pdPASS;
 }
-
-GwUserCode userCodeHandler(new ApiImpl(MIN_USER_TASK),&mainLock);
+ApiImpl *apiImpl=new ApiImpl(MIN_USER_TASK);
+GwUserCode userCodeHandler(apiImpl,&mainLock);
 
 #define JSON_OK "{\"status\":\"OK\"}"