Add enum for TopicPartition offsets

include/cppkafka/topic_partition.h

@@ -40,6 +40,16 @@ namespace cppkafka {
  */
 class TopicPartition {
 public:
+    /**
+     * Special offsets enum
+     */
+    enum Offset {
+        OFFSET_BEGINNING = -2,
+        OFFSET_END = -1,
+        OFFSET_STORED = -1000,
+        OFFSET_INVALID = -1001
+    };
+
     /**
      * Default constructs a topic/partition
      */

tests/topic_partition_list_test.cpp

@@ -13,6 +13,7 @@ TEST_F(TopicPartitionListTest, Conversion) {
     TopicPartitionList list1;
     list1.push_back("foo");
     list1.push_back({ "bar", 2 });
+    list1.push_back({ "asd", 2, TopicPartition::OFFSET_BEGINNING });
 
     TopicPartitionList list2 = convert(convert(list1));