Builder pattern applied to data sources

app/data/__init__.py

@@ -2,6 +2,7 @@
 from ..services.location.csbs import CSBSLocationService
 from ..services.location.jhu import JhuLocationService
 from ..services.location.nyt import NYTLocationService
+from abc import ABCMeta, abstractmethod
 
 # Mapping of services to data-sources.
 DATA_SOURCES = {
@@ -10,7 +11,6 @@
     "nyt": NYTLocationService(),
 }
 
-
 def data_source(source):
     """
     Retrieves the provided data-source service.
@@ -19,3 +19,44 @@ def data_source(source):
     :rtype: LocationService
     """
     return DATA_SOURCES.get(source.lower())
+
+
+class LocationAssembler:
+    """The Director"""
+    builder = None
+
+    def setBuilder(self,builder):
+        self.builder = builder
+
+    def getSource(self):
+        product = LocationSource()
+        source = self.builder.getDataSource()
+        product.setDataSource(source)
+
+class LocationSource:
+    """The Product"""
+    def __init__(self):
+        self.datasource = None
+
+    def setDataSource(self, dataSource):
+        self.dataSource = dataSource
+
+class LocationSourceBuilder(metaclass=ABCMeta):
+    """The Interface"""
+    @abstractmethod
+    def getDataSource(self): pass
+
+class JHUBuilder(LocationSourceBuilder):
+    """The Concrete Builder"""
+    def getDataSource(self):
+        return DATA_SOURCES.get("jhu")
+
+class CSBSBuilder(LocationSourceBuilder):
+    """The Concrete Builder"""
+    def getDataSource(self):
+        return DATA_SOURCES.get("csbs")
+
+class NYTBuilder(LocationSourceBuilder):
+    """The Concrete Builder"""
+    def getDataSource(self):
+        return DATA_SOURCES.get("nyt")