decoder: Add a decoder test case for Fluent Bit V2 format

Signed-off-by: Hiroshi Hatake <hatake@calyptia.com>

Author: cosmo0920

output/decoder_test.go

@@ -33,6 +33,19 @@ var dummyRecord [29]byte = [29]byte{0x92, /* fix array 2 */
 	0x01, /* fix int 1 */
 }
 
+// dummyV2Record should be byte Array, not Slice to be able to Cast c array.
+var dummyV2Record [39]byte = [39]byte{0xdd, /* array 32 */ 0x00, 0x00, 0x00,
+	0x02, /* count of array elements */
+	0xdd,  /* array 32 */ 0x00, 0x00, 0x00,
+	0x02,  /* count of array elements */
+	0xd7, 0x00, 0x64, 0xbe, 0x0e, 0xeb, 0x16, 0x36, 0xe1, 0x28, 0x80, /* 2023/07/24 14:40:59 */
+	0x82,                                           /* fix map 2 */
+	0xa7, 0x63, 0x6f, 0x6d, 0x70, 0x61, 0x63, 0x74, /* fix str 7 "compact" */
+	0xc3,                                           /* true */
+	0xa6, 0x73, 0x63, 0x68, 0x65, 0x6d, 0x61,  /* fix str 6 "schema" */
+	0x01,  /* fix int 1 */
+}
+
 func TestGetRecord(t *testing.T) {
 	dec := NewDecoder(unsafe.Pointer(&dummyRecord), len(dummyRecord))
 	if dec == nil {
@@ -63,3 +76,34 @@ func TestGetRecord(t *testing.T) {
 		t.Errorf(`record["schema"] is not 1 %d`, v)
 	}
 }
+
+func TestGetV2Record(t *testing.T) {
+	dec := NewDecoder(unsafe.Pointer(&dummyV2Record), len(dummyV2Record))
+	if dec == nil {
+		t.Fatal("dec is nil")
+	}
+
+	ret, timestamp, record := GetRecord(dec)
+	if ret < 0 {
+		t.Fatalf("ret is negative: code %v", ret)
+	}
+
+	// test timestamp
+	ts, ok := timestamp.(FLBTime)
+	if !ok {
+		t.Fatalf("cast error. Type is %s", reflect.TypeOf(timestamp))
+	}
+
+	if ts.Unix() != int64(0x64be0eeb) {
+		t.Errorf("ts.Unix() error. given %d", ts.Unix())
+	}
+
+	// test record
+	v, ok := record["schema"].(int64)
+	if !ok {
+		t.Fatalf("cast error. Type is %s", reflect.TypeOf(record["schema"]))
+	}
+	if v != 1 {
+		t.Errorf(`record["schema"] is not 1 %d`, v)
+	}
+}