Added UTs

Signed-off-by: Athish Pranav D <[email protected]>

test/plugin/test_in_forward.rb

@@ -508,7 +508,7 @@ def create_driver(conf=base_config)
   end
 
   sub_test_case 'compressed packed forward' do
-    test 'set_compress_to_option' do
+    test 'set_compress_to_option_gzip' do
       @d = d = create_driver
 
       time_i = event_time("2011-01-02 13:14:15 UTC").to_i
@@ -535,6 +535,33 @@ def create_driver(conf=base_config)
       assert_equal events, d.events
     end
 
+    test 'set_compress_to_option_zstd' do
+      @d = d = create_driver
+
+      time_i = event_time("2011-01-02 13:14:15 UTC").to_i
+      events = [
+        ["tag1", time_i, {"a"=>1}],
+        ["tag1", time_i, {"a"=>2}]
+      ]
+
+      # create compressed entries
+      entries = ''
+      events.each do |_tag, _time, record|
+        v = [_time, record].to_msgpack
+        entries << compress(v, type: :zstd)
+      end
+      chunk = ["tag1", entries, { 'compressed' => 'zstd' }].to_msgpack
+
+      d.run do
+        Fluent::MessagePackFactory.msgpack_unpacker.feed_each(chunk) do |obj|
+          option = d.instance.send(:on_message, obj, chunk.size, DUMMY_SOCK)
+          assert_equal 'zstd', option['compressed']
+        end
+      end
+
+      assert_equal events, d.events
+    end
+
     test 'create_CompressedMessagePackEventStream_with_gzip_compress_option' do
       @d = d = create_driver
 
@@ -562,6 +589,34 @@ def create_driver(conf=base_config)
         end
       end
     end
+
+    test 'create_CompressedMessagePackEventStream_with_zstd_compress_option' do
+      @d = d = create_driver
+
+      time_i = event_time("2011-01-02 13:14:15 UTC").to_i
+      events = [
+        ["tag1", time_i, {"a"=>1}],
+        ["tag1", time_i, {"a"=>2}]
+      ]
+
+      # create compressed entries
+      entries = ''
+      events.each do |_tag, _time, record|
+        v = [_time, record].to_msgpack
+        entries << compress(v)
+      end
+      chunk = ["tag1", entries, { 'compressed' => 'zstd' }].to_msgpack
+
+      # check CompressedMessagePackEventStream is created
+      mock(Fluent::CompressedMessagePackEventStream).new(entries, nil, 0, compress: :zstd)
+
+      d.run do
+        Fluent::MessagePackFactory.msgpack_unpacker.feed_each(chunk) do |obj|
+          option = d.instance.send(:on_message, obj, chunk.size, DUMMY_SOCK)
+          assert_equal 'zstd', option['compressed']
+        end
+      end
+    end
   end
 
   sub_test_case 'warning' do