First commit to enable callbacks (ckoepp#25)

TwitterSearch/TwitterSearch.py

@@ -108,6 +108,9 @@ def __init__(self, consumer_key, consumer_secret,
         # statistics
         self.__statistics = [0,0]
 
+        # callback
+        self.__callback = None
+
         # verify
         if "verify" in attr:
             self.authenticate(attr["verify"])
@@ -181,16 +184,23 @@ def check_http_status(self, http_status):
             raise TwitterSearchException(http_status,
                                          self.exceptions[http_status])
 
-    def search_tweets_iterable(self, order):
+    def search_tweets_iterable(self, order, callback=None):
         """ Returns itself and queries the Twitter API. Is called when using \
         an instance of this class as iterable. \
         See `Basic usage <basic_usage.html>`_ for examples
 
         :param order: An instance of TwitterOrder class \
         (e.g. TwitterSearchOrder or TwitterUserOrder)
+        :param callback: Function to be called after a new page \
+        is queried from the Twitter API
         :returns: Itself using ``self`` keyword
         """
 
+        if callback:
+            if not callable(callback):
+                raise TwitterSearchException(1018)
+            self.__callback = callback
+
         self.search_tweets(order)
         return self
 
@@ -242,6 +252,10 @@ def send_search(self, url):
         self.__statistics[0] += 1
         self.__statistics[1] += seen_tweets
 
+        # call callback if available
+        if self.__callback:
+            self.__callback(self)
+
         # if we've seen the correct amount of tweets there may be some more
         # using IDs to request more results
         # (former versions used page parameter)

TwitterSearch/TwitterSearchException.py

@@ -30,6 +30,7 @@ class TwitterSearchException(Exception):
         1015: 'No keywords given',
         1016: 'Invalid dict',
         1017: 'Invalid argument: need either a user ID or a screen-name',
+        1018: 'Not a callable function',
     }
 
     def __init__(self, code, msg=None):