kafka(ticdc): event router allow hard code topics and set the schema optional in the topic expression (#9755)

cdc/sink/mq/dispatcher/event_router.go

@@ -78,7 +78,7 @@ type EventRouter struct {
 }
 
 // NewEventRouter creates a new EventRouter.
-func NewEventRouter(cfg *config.ReplicaConfig, defaultTopic string) (*EventRouter, error) {
+func NewEventRouter(cfg *config.ReplicaConfig, defaultTopic string, protocol config.Protocol) (*EventRouter, error) {
 	// If an event does not match any dispatching rules in the config file,
 	// it will be dispatched by the default partition dispatcher and
 	// static topic dispatcher because it matches *.* rule.
@@ -103,7 +103,7 @@ func NewEventRouter(cfg *config.ReplicaConfig, defaultTopic string) (*EventRoute
 		}
 
 		d := getPartitionDispatcher(ruleConfig, cfg.EnableOldValue)
-		t, err := getTopicDispatcher(ruleConfig, defaultTopic, cfg.Sink.Protocol)
+		t, err := getTopicDispatcher(ruleConfig.TopicRule, defaultTopic, protocol)
 		if err != nil {
 			return nil, err
 		}
@@ -251,32 +251,31 @@ func getPartitionDispatcher(
 
 // getTopicDispatcher returns the topic dispatcher for a specific topic rule (aka topic expression).
 func getTopicDispatcher(
-	ruleConfig *config.DispatchRule, defaultTopic string, protocol string,
+	rule string, defaultTopic string, protocol config.Protocol,
 ) (topic.Dispatcher, error) {
-	if ruleConfig.TopicRule == "" {
+	if rule == "" {
 		return topic.NewStaticTopicDispatcher(defaultTopic), nil
 	}
 
-	// check if this rule is a valid topic expression
-	topicExpr := topic.Expression(ruleConfig.TopicRule)
-
-	if protocol != "" {
-		p, err := config.ParseSinkProtocolFromString(protocol)
-		if err != nil {
-			return nil, cerror.WrapError(cerror.ErrKafkaInvalidConfig, err)
-		}
+	if topic.IsHardCode(rule) {
+		return topic.NewStaticTopicDispatcher(rule), nil
+	}
 
-		if p == config.ProtocolAvro {
-			err := topicExpr.ValidateForAvro()
-			if err != nil {
-				return nil, err
-			}
-		} else {
-			err := topicExpr.Validate()
-			if err != nil {
-				return nil, err
-			}
-		}
+	// check if this rule is a valid topic expression
+	topicExpr := topic.Expression(rule)
+	err := validateTopicExpression(topicExpr, protocol)
+	if err != nil {
+		return nil, err
 	}
 	return topic.NewDynamicTopicDispatcher(topicExpr), nil
 }
+
+func validateTopicExpression(expr topic.Expression, protocol config.Protocol) error {
+	switch protocol {
+	case config.ProtocolAvro:
+		return expr.ValidateForAvro()
+	default:
+	}
+
+	return expr.Validate()
+}

cdc/sink/mq/dispatcher/event_router_test.go

@@ -24,78 +24,112 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestEventRouter(t *testing.T) {
-	t.Parallel()
-
-	d, err := NewEventRouter(config.GetDefaultReplicaConfig(), "test")
-	require.Nil(t, err)
-	require.Equal(t, "test", d.GetDefaultTopic())
-	topicDispatcher, partitionDispatcher := d.matchDispatcher("test", "test")
-	require.IsType(t, &topic.StaticTopicDispatcher{}, topicDispatcher)
-	require.IsType(t, &partition.DefaultDispatcher{}, partitionDispatcher)
-
-	d, err = NewEventRouter(&config.ReplicaConfig{
+func newReplicaConfig4DispatcherTest() *config.ReplicaConfig {
+	return &config.ReplicaConfig{
 		Sink: &config.SinkConfig{
 			DispatchRules: []*config.DispatchRule{
+				// rule-0
 				{
 					Matcher:       []string{"test_default1.*"},
 					PartitionRule: "default",
 				},
+				// rule-1
 				{
 					Matcher:       []string{"test_default2.*"},
 					PartitionRule: "unknown-dispatcher",
 				},
+				// rule-2
 				{
 					Matcher:       []string{"test_table.*"},
 					PartitionRule: "table",
 					TopicRule:     "hello_{schema}_world",
 				},
+				// rule-3
 				{
 					Matcher:       []string{"test_index_value.*"},
 					PartitionRule: "index-value",
 					TopicRule:     "{schema}_world",
 				},
+				// rule-4
 				{
 					Matcher:       []string{"test.*"},
 					PartitionRule: "rowid",
 					TopicRule:     "hello_{schema}",
 				},
+				// rule-5
 				{
 					Matcher:       []string{"*.*", "!*.test"},
 					PartitionRule: "ts",
 					TopicRule:     "{schema}_{table}",
 				},
+				// rule-6: hard code the topic
+				{
+					Matcher:       []string{"hard_code_schema.*"},
+					PartitionRule: "default",
+					TopicRule:     "hard_code_topic",
+				},
 			},
 		},
-	}, "")
-	require.Nil(t, err)
-	topicDispatcher, partitionDispatcher = d.matchDispatcher("test", "table1")
-	require.IsType(t, &topic.DynamicTopicDispatcher{}, topicDispatcher)
-	require.IsType(t, &partition.IndexValueDispatcher{}, partitionDispatcher)
+	}
+}
 
-	topicDispatcher, partitionDispatcher = d.matchDispatcher("sbs", "table2")
-	require.IsType(t, &topic.DynamicTopicDispatcher{}, topicDispatcher)
-	require.IsType(t, &partition.TsDispatcher{}, partitionDispatcher)
+func TestEventRouter(t *testing.T) {
+	t.Parallel()
+
+	replicaConfig := config.GetDefaultReplicaConfig()
+	d, err := NewEventRouter(replicaConfig, "test", config.ProtocolCanalJSON)
+	require.NoError(t, err)
+	require.Equal(t, "test", d.GetDefaultTopic())
 
+	topicDispatcher, partitionDispatcher := d.matchDispatcher("test", "test")
+	require.IsType(t, &topic.StaticTopicDispatcher{}, topicDispatcher)
+	require.IsType(t, &partition.DefaultDispatcher{}, partitionDispatcher)
+
+	actual := topicDispatcher.Substitute("test", "test")
+	require.Equal(t, d.defaultTopic, actual)
+
+	replicaConfig = newReplicaConfig4DispatcherTest()
+	d, err = NewEventRouter(replicaConfig, "", config.ProtocolCanalJSON)
+	require.NoError(t, err)
+
+	// no matched, use the default
 	topicDispatcher, partitionDispatcher = d.matchDispatcher("sbs", "test")
 	require.IsType(t, &topic.StaticTopicDispatcher{}, topicDispatcher)
 	require.IsType(t, &partition.DefaultDispatcher{}, partitionDispatcher)
 
+	// match rule-0
 	topicDispatcher, partitionDispatcher = d.matchDispatcher("test_default1", "test")
 	require.IsType(t, &topic.StaticTopicDispatcher{}, topicDispatcher)
 	require.IsType(t, &partition.DefaultDispatcher{}, partitionDispatcher)
 
+	// match rule-1
 	topicDispatcher, partitionDispatcher = d.matchDispatcher("test_default2", "test")
 	require.IsType(t, &topic.StaticTopicDispatcher{}, topicDispatcher)
 	require.IsType(t, &partition.DefaultDispatcher{}, partitionDispatcher)
 
+	// match rule-2
 	topicDispatcher, partitionDispatcher = d.matchDispatcher("test_table", "test")
 	require.IsType(t, &topic.DynamicTopicDispatcher{}, topicDispatcher)
 	require.IsType(t, &partition.TableDispatcher{}, partitionDispatcher)
 
+	// match rule-4
 	topicDispatcher, partitionDispatcher = d.matchDispatcher("test_index_value", "test")
 	require.IsType(t, &topic.DynamicTopicDispatcher{}, topicDispatcher)
 	require.IsType(t, &partition.IndexValueDispatcher{}, partitionDispatcher)
+
+	// match rule-4
+	topicDispatcher, partitionDispatcher = d.matchDispatcher("test", "table1")
+	require.IsType(t, &topic.DynamicTopicDispatcher{}, topicDispatcher)
+	require.IsType(t, &partition.IndexValueDispatcher{}, partitionDispatcher)
+
+	topicDispatcher, partitionDispatcher = d.matchDispatcher("sbs", "table2")
+	require.IsType(t, &topic.DynamicTopicDispatcher{}, topicDispatcher)
+	require.IsType(t, &partition.TsDispatcher{}, partitionDispatcher)
+
+	// match rule-6
+	topicDispatcher, partitionDispatcher = d.matchDispatcher("hard_code_schema", "test")
+	require.IsType(t, &topic.StaticTopicDispatcher{}, topicDispatcher)
+	require.IsType(t, &partition.DefaultDispatcher{}, partitionDispatcher)
 }
 
 func TestGetActiveTopics(t *testing.T) {
@@ -134,7 +168,7 @@ func TestGetActiveTopics(t *testing.T) {
 				},
 			},
 		},
-	}, "test")
+	}, "test", config.ProtocolCanalJSON)
 	require.Nil(t, err)
 	names := []model.TableName{
 		{Schema: "test_default1", Table: "table"},
@@ -184,7 +218,7 @@ func TestGetTopicForRowChange(t *testing.T) {
 				},
 			},
 		},
-	}, "test")
+	}, "test", config.ProtocolCanalJSON)
 	require.Nil(t, err)
 
 	topicName := d.GetTopicForRowChange(&model.RowChangedEvent{
@@ -245,7 +279,7 @@ func TestGetPartitionForRowChange(t *testing.T) {
 				},
 			},
 		},
-	}, "test")
+	}, "test", config.ProtocolCanalJSON)
 	require.Nil(t, err)
 
 	p := d.GetPartitionForRowChange(&model.RowChangedEvent{
@@ -313,7 +347,7 @@ func TestGetDLLDispatchRuleByProtocol(t *testing.T) {
 				},
 			},
 		},
-	}, "test")
+	}, "test", config.ProtocolCanalJSON)
 	require.Nil(t, err)
 
 	tests := []struct {
@@ -374,7 +408,7 @@ func TestGetTopicForDDL(t *testing.T) {
 				},
 			},
 		},
-	}, "test")
+	}, "test", config.ProtocolCanalJSON)
 	require.Nil(t, err)
 
 	tests := []struct {

cdc/sink/mq/dispatcher/topic/dispatcher.go

@@ -23,28 +23,28 @@ type Dispatcher interface {
 	Substitute(schema, table string) string
 }
 
-// StaticTopicDispatcher is a topic dispatcher which dispatches rows and ddls to the default topic.
+// StaticTopicDispatcher is a topic dispatcher which dispatches rows and DDL to the specific topic.
 type StaticTopicDispatcher struct {
-	defaultTopic string
+	topic string
 }
 
 // NewStaticTopicDispatcher returns a StaticTopicDispatcher.
 func NewStaticTopicDispatcher(defaultTopic string) *StaticTopicDispatcher {
 	return &StaticTopicDispatcher{
-		defaultTopic: defaultTopic,
+		topic: defaultTopic,
 	}
 }
 
 // Substitute converts schema/table name in a topic expression to kafka topic name.
 func (s *StaticTopicDispatcher) Substitute(schema, table string) string {
-	return s.defaultTopic
+	return s.topic
 }
 
 func (s *StaticTopicDispatcher) String() string {
-	return s.defaultTopic
+	return s.topic
 }
 
-// DynamicTopicDispatcher is a topic dispatcher which dispatches rows and ddls
+// DynamicTopicDispatcher is a topic dispatcher which dispatches rows and DDLs
 // dynamically to the target topics.
 type DynamicTopicDispatcher struct {
 	expression Expression

cdc/sink/mq/dispatcher/topic/dispatcher_test.go

@@ -29,7 +29,8 @@ func TestDynamicTopicDispatcherForSchema(t *testing.T) {
 
 	topicExpr := Expression("hello_{schema}_world")
 	err := topicExpr.Validate()
-	require.Nil(t, err)
+	require.NoError(t, err)
+
 	testCase := []struct {
 		schema      string
 		table       string
@@ -68,7 +69,8 @@ func TestDynamicTopicDispatcherForTable(t *testing.T) {
 
 	topicExpr := Expression("{schema}_{table}")
 	err := topicExpr.Validate()
-	require.Nil(t, err)
+	require.NoError(t, err)
+
 	testCases := []struct {
 		schema        string
 		table         string

cdc/sink/mq/dispatcher/topic/expression.go

@@ -20,9 +20,12 @@ import (
 )
 
 var (
+	// hardCodeTopicNameRe is used to match a topic name which is hard code in the config
+	hardCodeTopicNameRe = regexp.MustCompile(`^([A-Za-z0-9\._\-]+)$`)
+
 	// topicNameRE is used to match a valid topic expression
 	topicNameRE = regexp.MustCompile(
-		`^[A-Za-z0-9\._\-]*\{schema\}([A-Za-z0-9\._\-]*\{table\})?[A-Za-z0-9\._\-]*$`,
+		`^[A-Za-z0-9\._\-]*(\{schema\})?([A-Za-z0-9\._\-]*\{table\})?[A-Za-z0-9\._\-]*$`,
 	)
 	// kafkaForbidRE is used to reject the characters which are forbidden in kafka topic name
 	kafkaForbidRE = regexp.MustCompile(`[^a-zA-Z0-9\._\-]`)
@@ -48,13 +51,14 @@ const kafkaTopicNameMaxLength = 249
 type Expression string
 
 // Validate checks whether a kafka topic name is valid or not.
+// return true if the expression is hard coded.
 func (e Expression) Validate() error {
 	// validate the topic expression
-	if ok := topicNameRE.MatchString(string(e)); !ok {
-		return errors.ErrKafkaInvalidTopicExpression.GenWithStackByArgs()
+	if ok := topicNameRE.MatchString(string(e)); ok {
+		return nil
 	}
 
-	return nil
+	return errors.ErrKafkaInvalidTopicExpression.GenWithStackByArgs()
 }
 
 // ValidateForAvro checks whether topic pattern is {schema}_{table}, the only allowed
@@ -94,3 +98,8 @@ func (e Expression) Substitute(schema, table string) string {
 		return topicName
 	}
 }
+
+// IsHardCode checks whether a topic name is hard code or not.
+func IsHardCode(topicName string) bool {
+	return hardCodeTopicNameRe.MatchString(topicName)
+}

cdc/sink/mq/dispatcher/topic/expression_test.go

@@ -227,6 +227,30 @@ func TestSubstituteTopicExpression(t *testing.T) {
 	}
 }
 
+func TestSchemaOptional(t *testing.T) {
+	expression := "prefix_{table}"
+	topicExpr := Expression(expression)
+	err := topicExpr.Validate()
+	require.NoError(t, err)
+
+	schemaName := "test"
+	tableName := "table1"
+	topicName := topicExpr.Substitute(schemaName, tableName)
+	require.Equal(t, topicName, "prefix_table1")
+}
+
+func TestTableOptional(t *testing.T) {
+	expression := "prefix_{schema}"
+	topicExpr := Expression(expression)
+	err := topicExpr.Validate()
+	require.NoError(t, err)
+
+	schemaName := "test"
+	tableName := "abc"
+	topicName := topicExpr.Substitute(schemaName, tableName)
+	require.Equal(t, topicName, "prefix_test")
+}
+
 // cmd: go test -run='^$' -bench '^(BenchmarkSubstitute)$' github.com/pingcap/tiflow/cdc/sink/dispatcher/topic
 // goos: linux
 // goarch: amd64

cdc/sink/mq/mq.go

@@ -76,7 +76,7 @@ func newMqSink(
 		return nil, cerror.WrapError(cerror.ErrKafkaInvalidConfig, err)
 	}
 
-	eventRouter, err := dispatcher.NewEventRouter(replicaConfig, defaultTopic)
+	eventRouter, err := dispatcher.NewEventRouter(replicaConfig, defaultTopic, encoderConfig.Protocol)
 	if err != nil {
 		return nil, errors.Trace(err)
 	}

cdc/sinkv2/ddlsink/mq/kafka_ddl_sink.go

@@ -108,7 +108,7 @@ func NewKafkaDDLSink(
 		return nil, errors.Trace(err)
 	}
 
-	eventRouter, err := dispatcher.NewEventRouter(replicaConfig, topic)
+	eventRouter, err := dispatcher.NewEventRouter(replicaConfig, topic, protocol)
 	if err != nil {
 		return nil, errors.Trace(err)
 	}