1 files changed, 14 insertions, 52 deletions
diff --git a/synapse/util/__init__.py b/synapse/util/__init__.py
index 756d8ffa32..fc11e26623 100644
--- a/synapse/util/__init__.py
+++ b/synapse/util/__init__.py
@@ -13,7 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.api.errors import SynapseError
 from synapse.util.logcontext import PreserveLoggingContext
 
 from twisted.internet import defer, reactor, task
@@ -21,12 +20,9 @@ from twisted.internet import defer, reactor, task
 import time
 import logging
 
-logger = logging.getLogger(__name__)
-
+from itertools import islice
 
-class DeferredTimedOutError(SynapseError):
-    def __init__(self):
-        super(DeferredTimedOutError, self).__init__(504, "Timed out")
+logger = logging.getLogger(__name__)
 
 
 def unwrapFirstError(failure):
@@ -86,52 +82,18 @@ class Clock(object):
             if not ignore_errs:
                 raise
 
-    def time_bound_deferred(self, given_deferred, time_out):
-        if given_deferred.called:
-            return given_deferred
-
-        ret_deferred = defer.Deferred()
-
-        def timed_out_fn():
-            e = DeferredTimedOutError()
-
-            try:
-                ret_deferred.errback(e)
-            except Exception:
-                pass
-
-            try:
-                given_deferred.cancel()
-            except Exception:
-                pass
 
-        timer = None
+def batch_iter(iterable, size):
+    """batch an iterable up into tuples with a maximum size
 
-        def cancel(res):
-            try:
-                self.cancel_call_later(timer)
-            except Exception:
-                pass
-            return res
+    Args:
+        iterable (iterable): the iterable to slice
+        size (int): the maximum batch size
 
-        ret_deferred.addBoth(cancel)
-
-        def success(res):
-            try:
-                ret_deferred.callback(res)
-            except Exception:
-                pass
-
-            return res
-
-        def err(res):
-            try:
-                ret_deferred.errback(res)
-            except Exception:
-                pass
-
-        given_deferred.addCallbacks(callback=success, errback=err)
-
-        timer = self.call_later(time_out, timed_out_fn)
-
-        return ret_deferred
+    Returns:
+        an iterator over the chunks
+    """
+    # make sure we can deal with iterables like lists too
+    sourceiter = iter(iterable)
+    # call islice until it returns an empty tuple
+    return iter(lambda: tuple(islice(sourceiter, size)), ())