Support JSON data type (#118)

* Support JSON column type

* Add test case for JSON null

decoder.go

@@ -153,6 +153,17 @@ func DecodeColumn(column spanner.GenericColumnValue) (string, error) {
 				}
 				decoded = append(decoded, fmt.Sprintf("[%s]", strings.Join(columns, ", ")))
 			}
+		case sppb.TypeCode_JSON:
+			var vs []spanner.NullJSON
+			if err := column.Decode(&vs); err != nil {
+				return "", err
+			}
+			if vs == nil {
+				return "NULL", nil
+			}
+			for _, v := range vs {
+				decoded = append(decoded, nullJSONToString(v))
+			}
 		}
 		return fmt.Sprintf("[%s]", strings.Join(decoded, ", ")), nil
 	case sppb.TypeCode_BOOL:
@@ -203,6 +214,12 @@ func DecodeColumn(column spanner.GenericColumnValue) (string, error) {
 			return "", err
 		}
 		return nullDateToString(v), nil
+	case sppb.TypeCode_JSON:
+		var v spanner.NullJSON
+		if err := column.Decode(&v); err != nil {
+			return "", err
+		}
+		return nullJSONToString(v), nil
 	default:
 		return fmt.Sprintf("%s", column.Value), nil
 	}
@@ -273,3 +290,11 @@ func nullDateToString(v spanner.NullDate) string {
 		return "NULL"
 	}
 }
+
+func nullJSONToString(v spanner.NullJSON) string {
+	if v.Valid {
+		return v.String()
+	} else {
+		return "NULL"
+	}
+}

decoder_test.go

@@ -68,6 +68,10 @@ func equalStringSlice(a []string, b []string) bool {
 	return true
 }
 
+type jsonMessage struct {
+	Msg string `json:"msg"`
+}
+
 func TestDecodeColumn(t *testing.T) {
 	tests := []struct {
 		desc  string
@@ -115,6 +119,16 @@ func TestDecodeColumn(t *testing.T) {
 			value: civil.DateOf(time.Unix(1516676400, 0)),
 			want:  "2018-01-23",
 		},
+		{
+			desc:  "json",
+			value: spanner.NullJSON{Value: jsonMessage{Msg: "foo"}, Valid: true},
+			want:  `{"msg":"foo"}`,
+		},
+		{
+			desc:  "json null is not NULL",
+			value: spanner.NullJSON{Value: nil, Valid: true},
+			want:  `null`,
+		},
 
 		// nullable
 		{
@@ -157,6 +171,11 @@ func TestDecodeColumn(t *testing.T) {
 			value: spanner.NullDate{Date: civil.DateOf(time.Unix(0, 0)), Valid: false},
 			want:  "NULL",
 		},
+		{
+			desc:  "null json",
+			value: spanner.NullJSON{Value: nil, Valid: false},
+			want:  "NULL",
+		},
 
 		// array non-nullable
 		{
@@ -221,6 +240,14 @@ func TestDecodeColumn(t *testing.T) {
 			},
 			want: "[[10, Hello], [20, NULL]]",
 		},
+		{
+			desc: "array json",
+			value: []spanner.NullJSON{
+				{Value: jsonMessage{Msg: "foo"}, Valid: true},
+				{Value: jsonMessage{Msg: "bar"}, Valid: true},
+			},
+			want: `[{"msg":"foo"}, {"msg":"bar"}]`,
+		},
 
 		// array nullable
 		{
@@ -263,6 +290,11 @@ func TestDecodeColumn(t *testing.T) {
 			value: []civil.Date(nil),
 			want:  "NULL",
 		},
+		{
+			desc:  "null array json",
+			value: []spanner.NullJSON(nil),
+			want:  "NULL",
+		},
 	}
 
 	for _, test := range tests {

go.mod

@@ -3,16 +3,22 @@ module github.com/cloudspannerecosystem/spanner-cli
 go 1.13
 
 require (
-	cloud.google.com/go v0.79.0
-	cloud.google.com/go/spanner v1.17.0
+	cloud.google.com/go v0.93.3
+	cloud.google.com/go/spanner v1.25.0
 	github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e
-	github.com/google/go-cmp v0.5.5
+	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
+	github.com/google/go-cmp v0.5.6
+	github.com/googleapis/gax-go/v2 v2.1.0 // indirect
 	github.com/jessevdk/go-flags v1.4.0
 	github.com/mattn/go-runewidth v0.0.8 // indirect
 	github.com/olekukonko/tablewriter v0.0.4
 	github.com/xlab/treeprint v1.0.1-0.20200715141336-10e0bc383e01
-	google.golang.org/api v0.43.0
-	google.golang.org/genproto v0.0.0-20210331142528-b7513248f0ba
-	google.golang.org/grpc v1.36.1
-	google.golang.org/protobuf v1.26.0
+	golang.org/x/net v0.0.0-20210825183410-e898025ed96a // indirect
+	golang.org/x/oauth2 v0.0.0-20210819190943-2bc19b11175f // indirect
+	golang.org/x/sys v0.0.0-20210823070655-63515b42dcdf // indirect
+	golang.org/x/text v0.3.7 // indirect
+	google.golang.org/api v0.54.0
+	google.golang.org/genproto v0.0.0-20210830153122-0bac4d21c8ea
+	google.golang.org/grpc v1.40.0
+	google.golang.org/protobuf v1.27.1
 )