getting/setting configuration values from python works

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>

include/Configuration.h

@@ -161,7 +161,7 @@ class Configuration
 /// Return the value of a boolean key from the configuration
 bool get_config_bool(configuration_keys key);
 double get_config_double(configuration_keys key);
-rapidjson::Document get_config_as_json();
+void get_config_as_json(rapidjson::Document &doc);
 /// Get values in the configuration based as json data in string format
 std::string get_config_as_json_string();
 
@@ -173,7 +173,7 @@ void set_config_bool(configuration_keys key, bool val);
 void set_config_double(configuration_keys key, double val);
 void set_config_string(configuration_keys key, std::string val);
 /// Set values in the configuration based on a json file
-void set_config_json(rapidjson::Document & doc);
+void set_config_json(rapidjson::Document &doc);
 void set_config_as_json_string(std::string &s);
 }
 

src/Configuration.cpp

@@ -16,7 +16,7 @@ std::string config_key_to_string(configuration_keys keys)
     }
     // Back to a warning again
     #pragma GCC diagnostic warning "-Wswitch"
-    throw ValueError();
+    throw ValueError();// will never get here, just to make compiler happy
 }; 
 
 /// Go from string to enum key
@@ -44,21 +44,17 @@ double get_config_double(configuration_keys key){
 std::string get_config_string(configuration_keys key){ 
     return static_cast<std::string>(config.get_item(key)); 
 }
-rapidjson::Document get_config_as_json(){
-    // Init the rapidjson doc
-    rapidjson::Document doc;
-    doc.SetObject();
-    
+void get_config_as_json(rapidjson::Document &doc){
     // Get the items
     std::map<configuration_keys, ConfigurationItem> items = config.get_items();
     for (std::map<configuration_keys, ConfigurationItem>::iterator it = items.begin(); it != items.end(); ++it){
         it->second.add_to_json(doc, doc);
     }
-    // Convert to string
-    return doc;
 }
 std::string get_config_as_json_string(){
-    rapidjson::Document doc = get_config_as_json();
+    rapidjson::Document doc;
+    doc.SetObject();
+    get_config_as_json(doc);
     return cpjson::to_string(doc);
 }
 void set_config_as_json(rapidjson::Value &val){

wrappers/Python/CoolProp/CoolProp.pxd

@@ -18,6 +18,10 @@ cdef extern from "CoolPropTools.h" namespace "CoolProp":
 cdef extern from "Backends/Helmholtz/MixtureParameters.h" namespace "CoolProp":
     string _get_mixture_binary_pair_data "CoolProp::get_mixture_binary_pair_data"(const string CAS1, const string CAS2, const string key) except +
     
+cdef extern from "Configuration.h" namespace "CoolProp":    
+    string _get_config_as_json_string "CoolProp::get_config_as_json_string"() except +
+    void _set_config_as_json_string "CoolProp::set_config_as_json_string"(string) except +
+    
 cdef extern from "DataStructures.h" namespace "CoolProp":    
     string _get_parameter_information "CoolProp::get_parameter_information"(int, string) except +
     int _get_parameter_index "CoolProp::get_parameter_index"(string) except +

wrappers/Python/CoolProp/CoolProp.pyx

@@ -117,6 +117,12 @@ def set_reference_state(string FluidName, *args):
 #     else:
 #         return val
 
+cpdef string get_config_as_json_string():
+    return _get_config_as_json_string()
+
+cpdef set_config_as_json_string(string s):
+    _set_config_as_json_string(s)
+    
 cpdef int get_parameter_index(string key):
     return _get_parameter_index(key)