Merge pull request #4 from bw-hro/integer-input-for-double-properties

Integer input for double properties

Author: bw-hro

include/bw/webthing/property.hpp

@@ -23,24 +23,22 @@ json property_status_message(const Property<T>& property)
     });
 }
 
-
 template<class T>
 json property_value_object(const Property<T>& property)
 {
-
     auto value_as_json = property.get_value() ? json(*property.get_value()) : json();
     return json({{property.get_name(), value_as_json}});
 }
 
-
 class PropertyBase
 {
 public:
 
-	PropertyBase(std::string name, json metadata)
+    PropertyBase(std::string name, json metadata, bool wraps_double)
         : name(name)
         , metadata(metadata)
-	{
+        , wraps_double(wraps_double)
+    {
         if(this->metadata.type() != json::value_t::object)
             throw PropertyError("Only json::object is allowed as meta data.");
 
@@ -74,8 +72,8 @@ class PropertyBase
 
     std::string get_name() const
     {
-		return name;
-	}
+        return name;
+    }
 
     json get_metadata() const
     {
@@ -90,6 +88,9 @@ class PropertyBase
     template<class T> void set_value(T value)
     {
         try{
+           if(wraps_double && !std::is_same_v<T, double>)
+               return set_value(try_static_cast<double>(value));
+
             auto property = dynamic_cast<Property<T>&>(*this);
             property.set_value(value);
         }
@@ -100,10 +101,11 @@ class PropertyBase
     }
 
 protected:
-	std::string name;
+    std::string name;
     std::string href_prefix;
     std::string href;
     json metadata;
+    const bool wraps_double;
 };
 
 typedef std::function<void (json)> PropertyChangedCallback;
@@ -112,16 +114,15 @@ template<class T>
 class Property : public PropertyBase
 {
 public:
-	
-	Property(PropertyChangedCallback changed_callback, std::string name, std::shared_ptr<Value<T>> value, json metadata = json::object())
-		: PropertyBase(name, metadata)
+    Property(PropertyChangedCallback changed_callback, std::string name, std::shared_ptr<Value<T>> value, json metadata = json::object())
+        : PropertyBase(name, metadata, std::is_same_v<T, double>)
         , property_change_callback(changed_callback)
         , value(value)
-	{
+    {
         // Add value change observer to notify the Thing about a property change.
         if(property_change_callback)
             this->value->add_observer([&](auto v){property_change_callback(property_status_message(*this));});
-	}
+    }
 
     // Validate new proptery value before setting it.
     void validate_value(const T& value) const
@@ -164,7 +165,7 @@ class Property : public PropertyBase
     }
 
 private:
-	std::shared_ptr<Value<T>> value;
+    std::shared_ptr<Value<T>> value;
     PropertyChangedCallback property_change_callback;
 };
 

include/bw/webthing/utils.hpp

@@ -261,5 +261,19 @@ struct fix_uuid_scoped
 
 #define FIXED_UUID_SCOPED(uuid) auto fixed_uuid_scope_guard = fix_uuid_scoped(uuid);
 
+// try to static_cast from a type to another, throws std::bad_cast on error
+template<class To, class From>
+inline To try_static_cast(const From& value)
+{
+    try
+    {
+        if constexpr (std::is_convertible_v<From, To>)
+            return static_cast<To>(value);
+    }
+    catch(...)
+    {}
+
+    throw std::bad_cast();
+}
 
 } // bw::webthing

test/unit-test/property_tests.cpp

@@ -116,7 +116,7 @@ TEST_CASE( "Properties can wrap json values", "[property]" )
 
 TEST_CASE( "Properties can only be changed from external when provided values are valid", "[property]" )
 {
-    SECTION( "Number" )
+    SECTION( "Integer" )
     {
         auto val = create_value(666);
         json property_description = {{"type", "integer"}, {"minimum", 555}};
@@ -128,10 +128,34 @@ TEST_CASE( "Properties can only be changed from external when provided values ar
         );
         REQUIRE( *property->get_value<int>() == 666 );
 
+        REQUIRE_THROWS_MATCHES(property->set_value(777.0), PropertyError,
+            MessageContains("value type not matching")
+        );
+        REQUIRE( *property->get_value<int>() == 666 );
+
         property->set_value(1000);
         REQUIRE( *property->get_value<int>() == 1000 );
     }
 
+    SECTION( "Number" )
+    {
+        auto val = create_value(666.0);
+        json property_description = {{"type", "number"}, {"minimum", 555.0}};
+        auto property = create_proptery("writeable-number-prop", val, property_description);
+
+        REQUIRE_THROWS_MATCHES(property->set_value(123.0), PropertyError,
+            MessageContains("Invalid property") &&
+            MessageContains("below minimum of 555")
+        );
+        REQUIRE( *property->get_value<double>() == 666 );
+
+        property->set_value(1000.123);
+        REQUIRE( *property->get_value<double>() == 1000.123 );
+
+        property->set_value(777);
+        REQUIRE( *property->get_value<double>() == 777 );
+    }
+
     SECTION( "String" )
     {
         auto val = create_value(std::string("first-string-value"));

vcpkg-no-ssl.json

@@ -1,6 +1,6 @@
 {
     "name": "webthing-cpp",
-    "version-string": "1.0",
+    "version-string": "1.0.2",
     "dependencies": [
       "catch2",
       "json-schema-validator",

vcpkg-with-ssl.json

@@ -1,6 +1,6 @@
 {
     "name": "webthing-cpp",
-    "version-string": "1.0",
+    "version-string": "1.0.2",
     "dependencies": [
       "catch2",
       "json-schema-validator",

vcpkg.json

@@ -1,6 +1,6 @@
 {
     "name": "webthing-cpp",
-    "version-string": "1.0",
+    "version-string": "1.0.2",
     "dependencies": [
       "catch2",
       "json-schema-validator",