Structural pattern on location

app/data/__init__.py

@@ -1,21 +1,109 @@
 """app.data"""
+from abc import ABC, abstractmethod
 from ..services.location.csbs import CSBSLocationService
 from ..services.location.jhu import JhuLocationService
 from ..services.location.nyt import NYTLocationService
 
-# Mapping of services to data-sources.
+class DataSourceFactory(ABC):
+    def __init__(self):
+        pass
+
+    @abstractmethod 
+    def getInstance():
+        pass
+
+    @abstractmethod
+    def getService():
+        pass
+
+class JhuFactory(DataSourceFactory):
+    __instance = None
+    __service = None
+
+    def __init__(self):
+        if JhuFactory.__instance != None:
+            raise Exception("Factory is singleton!")
+        elif JhuFactory.__service != None:
+            raise Exception("Service is singleton!")
+        else:
+            JhuFactory.__instance = self
+            JhuFactory.__service = JhuLocationService()
+
+    @staticmethod 
+    def getInstance():
+      if JhuFactory.__instance == None:
+         JhuFactory()
+      return JhuFactory.__instance
+
+    @staticmethod 
+    def getService():
+      if JhuFactory.__service == None:
+         JhuFactory()
+      return JhuFactory.__service
+
+class CSBSFactory(DataSourceFactory):
+    __instance = None
+    __service = None
+
+    def __init__(self):
+        if CSBSFactory.__instance != None:
+            raise Exception("Factory is singleton!")
+        elif CSBSFactory.__service != None:
+            raise Exception("Service is singleton!")
+        else:
+            CSBSFactory.__instance = self
+            CSBSFactory.__service = CSBSLocationService()
+
+    @staticmethod 
+    def getInstance():
+      if CSBSFactory.__instance == None:
+         CSBSFactory()
+      return CSBSFactory.__instance
+
+    @staticmethod 
+    def getService():
+      if CSBSFactory.__service == None:
+         CSBSFactory()
+      return CSBSFactory.__service
+
+class NYTFactory(DataSourceFactory):
+    __instance = None
+    __service = None
+
+    def __init__(self):
+        if NYTFactory.__instance != None:
+            raise Exception("Factory is singleton!")
+        elif NYTFactory.__service != None:
+            raise Exception("Service is singleton!")
+        else:
+            NYTFactory.__instance = self
+            NYTFactory.__service = NYTLocationService()
+
+    @staticmethod 
+    def getInstance():
+      if NYTFactory.__instance == None:
+         NYTFactory()
+      return NYTFactory.__instance
+
+    @staticmethod 
+    def getService():
+      if NYTFactory.__service == None:
+         NYTFactory()
+      return NYTFactory.__service
+
+
+# Mapping of factories to data-sources.
 DATA_SOURCES = {
-    "jhu": JhuLocationService(),
-    "csbs": CSBSLocationService(),
-    "nyt": NYTLocationService(),
+    "jhu": JhuFactory.getInstance(),
+    "csbs": CSBSFactory.getInstance(),
+    "nyt": NYTFactory.getInstance(),
 }
 
-
 def data_source(source):
     """
     Retrieves the provided data-source service.
 
     :returns: The service.
     :rtype: LocationService
     """
-    return DATA_SOURCES.get(source.lower())
+    return DATA_SOURCES.get(source.lower()).getService()

app/location/__init__.py

@@ -74,6 +74,32 @@ def serialize(self):
         }
 
 
+def decoratedSerialize(func, inc_timelines, *args, **kwargs):
+    serialized = func()
+    if kwargs.get("timelines") and inc_timelines:
+        # Whether to include the timelines or not.
+        timelines = kwargs["timelines"]
+        if timelines:
+            serialized.update(
+                {
+                    "timelines": {
+                        # Serialize all the timelines.
+                        key: value.serialize()
+                        for (key, value) in self.timelines.items()
+                    }
+                }
+            )
+
+    if kwargs.get("state"):
+        state = kwargs["state"]
+        serialized.update({"state": state})
+
+    if kwargs.get("county"):
+        county = kwargs["county"]
+        serialized.update({"county": county})
+
+    return serialized
+
 class TimelinedLocation(Location):
     """
     A location with timelines.
@@ -96,29 +122,19 @@ def __init__(self, id, country, province, coordinates, last_updated, timelines):
 
         # Set timelines.
         self.timelines = timelines
+        self.inc_timelines = false
 
     # pylint: disable=arguments-differ
-    def serialize(self, timelines=False):
+    @decoratedSerialize(timelines=self.timelines, inc_timelines=self.inc_timelines)
+    def serialize(self, inc_timelines=false):
         """
         Serializes the location into a dict.
-
-        :param timelines: Whether to include the timelines.
+        :param inc_timelines: Whether to include the timelines.
         :returns: The serialized location.
         :rtype: dict
         """
         serialized = super().serialize()
-
-        # Whether to include the timelines or not.
-        if timelines:
-            serialized.update(
-                {
-                    "timelines": {
-                        # Serialize all the timelines.
-                        key: value.serialize()
-                        for (key, value) in self.timelines.items()
-                    }
-                }
-            )
+        self.inc_timelines = inc_timelines
 
         # Return the serialized location.
         return serialized

app/location/csbs.py

@@ -1,5 +1,6 @@
 """app.locations.csbs.py"""
 from . import Location
+from . import decoratedSerialize
 
 
 class CSBSLocation(Location):
@@ -25,19 +26,16 @@ def __init__(self, id, state, county, coordinates, last_updated, confirmed, deat
         self.state = state
         self.county = county
 
-    def serialize(self, timelines=False):  # pylint: disable=arguments-differ,unused-argument
+    @decoratedSerialize(state=self.state, county=self.county)
+    def serialize(self):  # pylint: disable=arguments-differ,unused-argument
         """
         Serializes the location into a dict.
 
+
         :returns: The serialized location.
         :rtype: dict
         """
         serialized = super().serialize()
 
-        # Update with new fields.
-        serialized.update(
-            {"state": self.state, "county": self.county,}
-        )
-
         # Return the serialized location.
         return serialized

app/location/nyt.py

@@ -1,5 +1,6 @@
 """app.locations.nyt.py"""
 from . import TimelinedLocation
+from . import decoratedSerialize
 
 
 class NYTLocation(TimelinedLocation):
@@ -14,19 +15,14 @@ def __init__(self, id, state, county, coordinates, last_updated, timelines):
         self.state = state
         self.county = county
 
-    def serialize(self, timelines=False):  # pylint: disable=arguments-differ,unused-argument
+    @decoratedSerialize(timelines=self.timelines, state=self.state, county=self.county)
+    def serialize(self, inc_timelines=False):  # pylint: disable=arguments-differ,unused-argument
         """
         Serializes the location into a dict.
-
         :returns: The serialized location.
         :rtype: dict
         """
-        serialized = super().serialize(timelines)
-
-        # Update with new fields.
-        serialized.update(
-            {"state": self.state, "county": self.county,}
-        )
+        serialized = super().serialize(inc_timelines)
 
         # Return the serialized location.
         return serialized