adding hex conversion to Bytes column

cqlengine/columns.py

@@ -195,6 +195,11 @@ class Column(object):
 class Bytes(Column):
     db_type = 'blob'
 
+    def to_database(self, value):
+        val = super(Bytes, self).to_database(value)
+        if val is None: return
+        return val.encode('hex')
+
 class Ascii(Column):
     db_type = 'ascii'
 

cqlengine/tests/columns/test_value_io.py

@@ -77,6 +77,12 @@ class BaseColumnIOTest(BaseCassEngTestCase):
             #delete
             self._generated_model.filter(pkey=pkey).delete()
 
+class TestBlobIO(BaseColumnIOTest):
+
+    column = columns.Bytes
+    pkey_val = 'blake', uuid4().bytes
+    data_val = 'eggleston', uuid4().bytes
+
 class TestTextIO(BaseColumnIOTest):
 
     column = columns.Text