First pass of cleanup/refactoring

Also added a bunch of docstrings

1 files changed, 25 insertions, 8 deletions

diff --git a/kafka/util.py b/kafka/util.py
index 6f27637..0623f35 100644
--- a/kafka/util.py
+++ b/kafka/util.py
@@ -1,38 +1,55 @@
+from itertools import groupby
 import struct
 
 def write_int_string(s):
-    return struct.pack('>i%ds' % len(s), len(s), s)
+    if s is None:
+        return struct.pack('>i', -1)
+    else:
+        return struct.pack('>i%ds' % len(s), len(s), s)
 
 def write_short_string(s):
-    return struct.pack('>H%ds' % len(s), len(s), s)
+    if s is None:
+        return struct.pack('>h', -1)
+    else:
+        return struct.pack('>h%ds' % len(s), len(s), s)
 
 def read_short_string(data, cur):
     if len(data) < cur+2:
-        raise IOError("Not enough data left")
-    (strLen,) = struct.unpack('>H', data[cur:cur+2])
+        raise BufferUnderflowError("Not enough data left")
+    (strLen,) = struct.unpack('>h', data[cur:cur+2])
     if strLen == -1:
         return (None, cur+2)
     cur += 2
     if len(data) < cur+strLen:
-        raise IOError("Not enough data left")
+        raise BufferUnderflowError("Not enough data left")
     out = data[cur:cur+strLen]
     return (out, cur+strLen)
 
 def read_int_string(data, cur):
     if len(data) < cur+4:
-        raise IOError("Not enough data left")
+        raise BufferUnderflowError("Not enough data left")
     (strLen,) = struct.unpack('>i', data[cur:cur+4])
     if strLen == -1:
         return (None, cur+4)
     cur += 4
     if len(data) < cur+strLen:
-        raise IOError("Not enough data left")
+        raise BufferUnderflowError("Not enough data left")
     out = data[cur:cur+strLen]
     return (out, cur+strLen)
 
 def relative_unpack(fmt, data, cur):
     size = struct.calcsize(fmt)
     if len(data) < cur+size:
-        raise IOError("Not enough data left")
+        raise BufferUnderflowError("Not enough data left")
     out = struct.unpack(fmt, data[cur:cur+size])
     return (out, cur+size)
+
+def group_list_by_key(l, key):
+    sorted_l = sorted(l, key=key)
+    return list(groupby(sorted_l, key=key))
+
+class BufferUnderflowError(Exception):
+    pass
+
+class ChecksumError(Exception):
+    pass