Just encode to bytes if it isn't bytes.

kafka/producer/simple.py

@@ -70,10 +70,12 @@ class SimpleProducer(Producer):
 
     def send_messages(self, topic, *msg):
         if not isinstance(topic, six.binary_type):
-            raise TypeError("topic must be type bytes")
+            topic = topic.encode('utf-8')
 
         partition = self._next_partition(topic)
-        return super(SimpleProducer, self).send_messages(topic, partition, *msg)
+        return super(SimpleProducer, self).send_messages(
+            topic, partition, *msg
+        )
 
     def __repr__(self):
         return '<SimpleProducer batch=%s>' % self.async

test/test_producer.py

@@ -7,6 +7,7 @@ from . import unittest
 
 from kafka.producer.base import Producer
 
+
 class TestKafkaProducer(unittest.TestCase):
     def test_producer_message_types(self):
 
@@ -28,11 +29,14 @@ class TestKafkaProducer(unittest.TestCase):
     def test_topic_message_types(self):
         from kafka.producer.simple import SimpleProducer
 
-        producer = SimpleProducer(MagicMock())
-        topic = "test-topic"
-        partition = 0
+        client = MagicMock()
 
-        def send_message():
-            producer.send_messages(topic, partition, b'hi')
+        def partitions(topic):
+            return [0, 1]
 
-        self.assertRaises(TypeError, send_message)
+        client.get_partition_ids_for_topic = partitions
+
+        producer = SimpleProducer(client, random_start=False)
+        topic = b"test-topic"
+        producer.send_messages(topic, b'hi')
+        assert client.send_produce_request.called