raise ValueError on protocol encode/decode errors

kafka/protocol/types.py

@@ -1,52 +1,63 @@
 from __future__ import absolute_import
 
-from struct import pack, unpack
+from struct import pack, unpack, error
 
 from .abstract import AbstractType
 
 
+def _pack(f, value):
+    try:
+        return pack(f, value)
+    except error:
+        raise ValueError(error)
+
+
+def _unpack(f, data):
+    try:
+        (value,) = unpack(f, data)
+        return value
+    except error:
+        raise ValueError(error)
+
+
 class Int8(AbstractType):
     @classmethod
     def encode(cls, value):
-        return pack('>b', value)
+        return _pack('>b', value)
 
     @classmethod
     def decode(cls, data):
-        (value,) = unpack('>b', data.read(1))
-        return value
+        return _unpack('>b', data.read(1))
 
 
 class Int16(AbstractType):
     @classmethod
     def encode(cls, value):
-        return pack('>h', value)
+        return _pack('>h', value)
 
     @classmethod
     def decode(cls, data):
-        (value,) = unpack('>h', data.read(2))
-        return value
+        return _unpack('>h', data.read(2))
 
 
 class Int32(AbstractType):
     @classmethod
     def encode(cls, value):
-        return pack('>i', value)
+        return _pack('>i', value)
 
     @classmethod
     def decode(cls, data):
-        (value,) = unpack('>i', data.read(4))
-        return value
+        return _unpack('>i', data.read(4))
 
 
 class Int64(AbstractType):
     @classmethod
     def encode(cls, value):
-        return pack('>q', value)
+        return _pack('>q', value)
 
     @classmethod
     def decode(cls, data):
-        (value,) = unpack('>q', data.read(8))
-        return value
+        return _unpack('>q', data.read(8))
 
 
 class String(AbstractType):
@@ -63,7 +74,10 @@ class String(AbstractType):
         length = Int16.decode(data)
         if length < 0:
             return None
-        return data.read(length).decode(self.encoding)
+        value = data.read(length)
+        if len(value) != length:
+            raise ValueError('Buffer underrun decoding string')
+        return value.decode(self.encoding)
 
 
 class Bytes(AbstractType):
@@ -79,7 +93,10 @@ class Bytes(AbstractType):
         length = Int32.decode(data)
         if length < 0:
             return None
-        return data.read(length)
+        value = data.read(length)
+        if len(value) != length:
+            raise ValueError('Buffer underrun decoding Bytes')
+        return value
 
 
 class Schema(AbstractType):