improve test and add changelog note

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+
+#### Unreleased
+
+Improvements:
+- Enabled producing with zstd compression
+  ([1574](https://github.com/Shopify/sarama/pull/1574))
+
+Known Issues:
+- Consuming zstd topics doesn't work right now
+
 #### Version 1.25.0 (2020-01-13)
 
 New Features:

zstd_test.go

@@ -12,18 +12,40 @@ func TestSaramaZSTD(t *testing.T) {
 	cfg.Producer.Retry.Max = 0
 	cfg.Producer.Compression = CompressionZSTD
 	cfg.Version = V2_1_0_0
+	kafkaHome := []string{"localhost:9092"}
+	topic := "my-zstd-topic"
 
-	producer, err := NewSyncProducer([]string{"localhost:9092"}, cfg)
+	admin, err := NewClusterAdmin(kafkaHome, cfg)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_ = admin.DeleteTopic(topic)
+	err = admin.CreateTopic(topic, &TopicDetail{NumPartitions: 1, ReplicationFactor: 1}, false)
+	if err.Error() != "kafka server: Topic with this name already exists. - Topic 'my-zstd-topic' already exists." {
+		t.Fatal(err)
+	}
+	defer func() {
+		if err := admin.Close(); err != nil {
+			t.Error(err)
+		}
+	}()
+
+	// producer
+	producer, err := NewSyncProducer(kafkaHome, cfg)
+	defer func() {
+		if err := producer.Close(); err != nil {
+			t.Error(err)
+		}
+	}()
 	if err != nil {
 		t.Fatalf("NewSyncProducer failed: %v", err)
 	}
 	_, _, err = producer.SendMessage(
 		&ProducerMessage{
-			Topic: "my-topic",
+			Topic: topic,
 			Value: StringEncoder("hello world!"),
 		})
 	if err != nil {
 		t.Errorf("TEST:   sending message failed: %v\n", err)
 	}
-	_ = producer.Close()
 }