Some refactoring to client.py

Author: mattbanister

client.py

@@ -1,25 +1,42 @@
 import requests
 
+
 class DiffbotClient(object):
     def __init__(self):
-        pass
+        self.base_url = "http://api.diffbot.com/"
 
     def request(self, url, token, api, fields=[], version=2):
         """
         Returns a python object containing the requested resource from the diffbot api
         """
         params = {"url": url, "token": token}
-        response = requests.get(self.get_url(api, version), params=params)
+        response = requests.get(self.compose_url(api, version), params=params)
         obj = response.json()
+        obj = self.select_fields_from_response(obj, fields)
+        return obj
+
+    @staticmethod
+    def select_fields_from_response(obj, fields):
+        """
+        Returns the response object with the specified fields or all fields if
+        the fields list is empty
+        """
         if fields:
-            obj = dict( (x, obj[x]) for x in fields)
+            obj = dict((x, obj[x]) for x in fields)
         return obj
 
-    def get_url(self, api, version):
+    def compose_url(self, api, version_number):
         """
         Returns the uri for an endpoint as a string
         """
-        base_url = "http://api.diffbot.com/"
-        version = "v" + str(version)
-        url = base_url + version + "/" + api
+        version = self.format_version_string(version_number)
+        url = self.base_url + version + "/" + api
         return url
+
+    @staticmethod
+    def format_version_string(version_number):
+        """
+        Returns a string representation of the API version
+        """
+        version = "v" + str(version_number)
+        return version