Change Build Topology to accept the routing key and topic (#27)

Original changes by @tobiasjaster in #19

go.mod

@@ -1,4 +1,4 @@
-module github.com/ThreeDotsLabs/watermill-amqp/v2
+module github.com/ThreeDotsLabs/watermill-amqp/v3
 
 go 1.21
 

pkg/amqp/config.go

@@ -32,11 +32,9 @@ func NewDurablePubSubConfig(amqpURI string, generateQueueName QueueNameGenerator
 		Marshaler: DefaultMarshaler{},
 
 		Exchange: ExchangeConfig{
-			GenerateName: func(topic string) string {
-				return topic
-			},
-			Type:    "fanout",
-			Durable: true,
+			GenerateName: GenerateExchangeNameTopicName,
+			Type:         "fanout",
+			Durable:      true,
 		},
 		Queue: QueueConfig{
 			GenerateName: generateQueueName,
@@ -61,13 +59,13 @@ func NewDurablePubSubConfig(amqpURI string, generateQueueName QueueNameGenerator
 	}
 }
 
-// NewNonDurablePubSubConfig creates config for non durable PubSub.
+// NewNonDurablePubSubConfig creates config for non-durable PubSub.
 // generateQueueName is optional, when passing to the publisher.
-// Exchange name is set to the topic name and routing key is empty.
+// Exchange name is set to the topic name and the routing key is empty.
 //
 // IMPORTANT: Watermill's topic is not mapped directly to the AMQP's topic exchange type.
 // It is used to generate exchange name, routing key and queue name, depending on the context.
-// To check how topic is mapped, please check Exchange.GenerateName, Queue.GenerateName and Publish.GenerateRoutingKey.
+// To check how the topic is mapped, please check Exchange.GenerateName, Queue.GenerateName and Publish.GenerateRoutingKey.
 //
 // This config is based on this example: https://www.rabbitmq.com/tutorials/tutorial-three-go.html.
 // This config is not durable, so on the restart of the broker all messages will be lost.
@@ -80,10 +78,8 @@ func NewNonDurablePubSubConfig(amqpURI string, generateQueueName QueueNameGenera
 		Marshaler: DefaultMarshaler{NotPersistentDeliveryMode: true},
 
 		Exchange: ExchangeConfig{
-			GenerateName: func(topic string) string {
-				return topic
-			},
-			Type: "fanout",
+			GenerateName: GenerateExchangeNameTopicName,
+			Type:         "fanout",
 		},
 		Queue: QueueConfig{
 			GenerateName: generateQueueName,
@@ -126,9 +122,7 @@ func NewDurableQueueConfig(amqpURI string) Config {
 		Marshaler: DefaultMarshaler{},
 
 		Exchange: ExchangeConfig{
-			GenerateName: func(topic string) string {
-				return ""
-			},
+			GenerateName: GenerateExchangeNameConstant(""),
 		},
 		Queue: QueueConfig{
 			GenerateName: GenerateQueueNameTopicName,
@@ -153,12 +147,12 @@ func NewDurableQueueConfig(amqpURI string) Config {
 	}
 }
 
-// NewNonDurableQueueConfig creates config for non durable Queue.
+// NewNonDurableQueueConfig creates config for non-durable Queue.
 // Queue name and routing key is set to the topic name by default. Default ("") exchange is used.
 //
 // IMPORTANT: Watermill's topic is not mapped directly to the AMQP's topic exchange type.
 // It is used to generate exchange name, routing key and queue name, depending on the context.
-// To check how topic is mapped, please check Exchange.GenerateName, Queue.GenerateName and Publish.GenerateRoutingKey.
+// To check how the topic is mapped, please check Exchange.GenerateName, Queue.GenerateName and Publish.GenerateRoutingKey.
 //
 // This config is based on this example: https://www.rabbitmq.com/tutorials/tutorial-two-go.html.
 // This config is not durable, so on the restart of the broker all messages will be lost.
@@ -171,9 +165,7 @@ func NewNonDurableQueueConfig(amqpURI string) Config {
 		Marshaler: DefaultMarshaler{NotPersistentDeliveryMode: true},
 
 		Exchange: ExchangeConfig{
-			GenerateName: func(topic string) string {
-				return ""
-			},
+			GenerateName: GenerateExchangeNameConstant(""),
 		},
 		Queue: QueueConfig{
 			GenerateName: GenerateQueueNameTopicName,
@@ -197,6 +189,79 @@ func NewNonDurableQueueConfig(amqpURI string) Config {
 	}
 }
 
+// NewDurableTopicConfig creates config for topic exchange for durable Queue.
+// Queue name and Exchange are set to the parameters.
+func NewDurableTopicConfig(amqpURI string, exchange string, queue string) Config {
+	return Config{
+		Connection: ConnectionConfig{
+			AmqpURI: amqpURI,
+		},
+
+		Marshaler: DefaultMarshaler{},
+
+		Exchange: ExchangeConfig{
+			GenerateName: GenerateExchangeNameConstant(exchange),
+			Type:         "topic",
+		},
+		Queue: QueueConfig{
+			GenerateName: GenerateQueueNameConstant(queue),
+			Durable:      true,
+		},
+		QueueBind: QueueBindConfig{
+			GenerateRoutingKey: func(topic string) string {
+				return topic
+			},
+		},
+		Publish: PublishConfig{
+			GenerateRoutingKey: func(topic string) string {
+				return topic
+			},
+		},
+		Consume: ConsumeConfig{
+			Qos: QosConfig{
+				PrefetchCount: 1,
+			},
+		},
+		TopologyBuilder: &DefaultTopologyBuilder{},
+	}
+}
+
+// NewNonDurableTopicConfig creates config for topic exchange for non-durable Queue.
+// Queue name and Exchange are set to the parameters.
+func NewNonDurableTopicConfig(amqpURI string, exchange string, queue string) Config {
+	return Config{
+		Connection: ConnectionConfig{
+			AmqpURI: amqpURI,
+		},
+
+		Marshaler: DefaultMarshaler{NotPersistentDeliveryMode: true},
+
+		Exchange: ExchangeConfig{
+			GenerateName: GenerateExchangeNameConstant(exchange),
+			Type:         "topic",
+		},
+		Queue: QueueConfig{
+			GenerateName: GenerateQueueNameConstant(queue),
+		},
+		QueueBind: QueueBindConfig{
+			GenerateRoutingKey: func(topic string) string {
+				return topic
+			},
+		},
+		Publish: PublishConfig{
+			GenerateRoutingKey: func(topic string) string {
+				return topic
+			},
+		},
+		Consume: ConsumeConfig{
+			Qos: QosConfig{
+				PrefetchCount: 1,
+			},
+		},
+		TopologyBuilder: &DefaultTopologyBuilder{},
+	}
+}
+
 type Config struct {
 	Connection ConnectionConfig
 
@@ -275,6 +340,21 @@ type ConnectionConfig struct {
 	Reconnect *ReconnectConfig
 }
 
+// QueueNameGenerator generates QueueName based on the topic.
+type ExchangeNameGenerator func(topic string) string
+
+// GenerateExchangeNameTopicName generates exchangeName equal to the topic.
+func GenerateExchangeNameTopicName(topic string) string {
+	return topic
+}
+
+// GenerateExchangeNameConstant generates exchangeName equal to exchangeName.
+func GenerateExchangeNameConstant(exchangeName string) ExchangeNameGenerator {
+	return func(topic string) string {
+		return exchangeName
+	}
+}
+
 // Config descriptions are based on descriptions from: https://github.com/streadway/amqp
 // Copyright (c) 2012, Sean Treadway, SoundCloud Ltd.
 // BSD 2-Clause "Simplified" License
@@ -287,7 +367,7 @@ type ExchangeConfig struct {
 	// "amq." if the passive option is set, or the exchange already exists.  Names can
 	// consist of a non-empty sequence of letters, digits, hyphen, underscore,
 	// period, or colon.
-	GenerateName func(topic string) string
+	GenerateName ExchangeNameGenerator
 
 	// Each exchange belongs to one of a set of exchange kinds/types implemented by
 	// the server. The exchange types define the functionality of the exchange - i.e.
@@ -352,7 +432,7 @@ func GenerateQueueNameTopicNameWithSuffix(suffix string) QueueNameGenerator {
 }
 
 type QueueConfig struct {
-	// GenerateRoutingKey is generated based on the topic provided for Subscribe.
+	// GenerateName generates the queue name based on the topic provided for Publish or Subscribe method.
 	GenerateName QueueNameGenerator
 
 	// Durable and Non-Auto-Deleted queues will survive server restarts and remain
@@ -377,12 +457,12 @@ type QueueConfig struct {
 	// delete a queue with the same name.
 	Exclusive bool
 
-	// When noWait is true, the queue will assume to be declared on the server.  A
-	// channel exception will arrive if the conditions are met for existing queues
+	// When NoWait is true, the queue is assumed to be declared on the server.
+	// A channel exception will arrive if the conditions are met for existing queues
 	// or attempting to modify an existing queue from a different connection.
 	NoWait bool
 
-	// Optional amqpe.Table of arguments that are specific to the server's implementation of
+	// Optional amqp.Table of arguments that are specific to the server's implementation of
 	// the queue can be sent for queue types that require extra parameters.
 	Arguments amqp.Table
 }
@@ -391,6 +471,7 @@ type QueueConfig struct {
 // be routed to the queue when the publishing routing key matches the binding
 // routing key.
 type QueueBindConfig struct {
+	// GenerateRoutingKey generates the routing key based on the topic provided Subscribe.
 	GenerateRoutingKey func(topic string) string
 
 	// When noWait is false and the queue could not be bound, the channel will be
@@ -403,7 +484,7 @@ type QueueBindConfig struct {
 }
 
 type PublishConfig struct {
-	// GenerateRoutingKey is generated based on the topic provided for Publish.
+	// GenerateRoutingKey generates the routing key based on the topic provided for Publish.
 	GenerateRoutingKey func(topic string) string
 
 	// Publishings can be undeliverable when the mandatory flag is true and no queue is
@@ -464,7 +545,7 @@ type ConsumeConfig struct {
 	Arguments amqp.Table
 }
 
-// Qos controls how many messages or how many bytes the server will try to keep on
+// QosConfig controls how many messages or how many bytes the server will try to keep on
 // the network for consumers before receiving delivery acks.  The intent of Qos is
 // to make sure the network buffers stay full between the server and client.
 type QosConfig struct {

pkg/amqp/correlatingmarshaler_test.go

@@ -4,7 +4,7 @@ import (
 	"testing"
 
 	"github.com/ThreeDotsLabs/watermill"
-	"github.com/ThreeDotsLabs/watermill-amqp/v2/pkg/amqp"
+	"github.com/ThreeDotsLabs/watermill-amqp/v3/pkg/amqp"
 	"github.com/ThreeDotsLabs/watermill/message"
 	stdAmqp "github.com/rabbitmq/amqp091-go"
 	"github.com/stretchr/testify/assert"

pkg/amqp/doc.go

@@ -7,7 +7,7 @@
 // - TLS support
 // - Publish Transactions support (optional, can be enabled in config)
 //
-// Nomenclature
+// # Nomenclature
 //
 // Unfortunately, Watermill's nomenclature is not fully compatible with AMQP's nomenclature.
 // Depending of the configuration, topic can be mapped to exchange name, routing key and queue name.

pkg/amqp/marshaler_test.go

@@ -4,7 +4,7 @@ import (
 	"testing"
 
 	"github.com/ThreeDotsLabs/watermill"
-	"github.com/ThreeDotsLabs/watermill-amqp/v2/pkg/amqp"
+	"github.com/ThreeDotsLabs/watermill-amqp/v3/pkg/amqp"
 	"github.com/ThreeDotsLabs/watermill/message"
 	stdAmqp "github.com/rabbitmq/amqp091-go"
 	"github.com/stretchr/testify/assert"

pkg/amqp/pubsub_reconnect_test.go

@@ -1,3 +1,4 @@
+//go:build reconnect
 // +build reconnect
 
 package amqp_test

pkg/amqp/pubsub_stress_test.go

@@ -1,3 +1,4 @@
+//go:build stress
 // +build stress
 
 package amqp_test

pkg/amqp/pubsub_test.go

@@ -9,7 +9,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/ThreeDotsLabs/watermill"
-	"github.com/ThreeDotsLabs/watermill-amqp/v2/pkg/amqp"
+	"github.com/ThreeDotsLabs/watermill-amqp/v3/pkg/amqp"
 	"github.com/ThreeDotsLabs/watermill/message"
 	"github.com/ThreeDotsLabs/watermill/pubsub/tests"
 )

pkg/amqp/subscriber.go

@@ -100,7 +100,7 @@ func NewSubscriberWithConnection(config Config, logger watermill.LoggerAdapter,
 
 // Subscribe consumes messages from AMQP broker.
 //
-// Watermill's topic in Subscribe is not mapped to AMQP's topic, but depending on configuration it can be mapped
+// Watermill's topic in Subscribe is not mapped to AMQP's topic, but depending on configuration, it can be mapped
 // to exchange, queue or routing key.
 // For detailed description of nomenclature mapping, please check "Nomenclature" paragraph in doc.go file.
 func (s *Subscriber) Subscribe(ctx context.Context, topic string) (<-chan *message.Message, error) {
@@ -122,7 +122,17 @@ func (s *Subscriber) Subscribe(ctx context.Context, topic string) (<-chan *messa
 	exchangeName := s.config.Exchange.GenerateName(topic)
 	logFields["amqp_exchange_name"] = exchangeName
 
-	if err := s.prepareConsume(queueName, exchangeName, logFields); err != nil {
+	routingKey := s.config.QueueBind.GenerateRoutingKey(topic)
+	logFields["amqp_routing_key"] = routingKey
+
+	params := BuildTopologyParams{
+		Topic:        topic,
+		QueueName:    queueName,
+		ExchangeName: exchangeName,
+		RoutingKey:   routingKey,
+	}
+
+	if err := s.prepareConsume(params, logFields); err != nil {
 		return nil, errors.Wrap(err, "failed to prepare consume")
 	}
 
@@ -137,7 +147,7 @@ func (s *Subscriber) Subscribe(ctx context.Context, topic string) (<-chan *messa
 			s.subscriberWaitGroup.Done()
 		}()
 
-	reconnecting := false
+		reconnecting := false
 	ReconnectLoop:
 		for {
 			s.logger.Debug("Waiting for s.connected or s.closing in ReconnectLoop", logFields)
@@ -155,7 +165,7 @@ func (s *Subscriber) Subscribe(ctx context.Context, topic string) (<-chan *messa
 			}
 
 			if reconnecting {
-				if err := s.prepareConsume(queueName, exchangeName, logFields); err != nil {
+				if err := s.prepareConsume(params, logFields); err != nil {
 					s.logger.Error("Failed to prepare consume", err, logFields)
 				}
 			}
@@ -164,7 +174,7 @@ func (s *Subscriber) Subscribe(ctx context.Context, topic string) (<-chan *messa
 			case <-s.connected:
 				s.logger.Debug("Connection established in ReconnectLoop", logFields)
 				// runSubscriber blocks until connection fails or Close() is called
-				s.runSubscriber(ctx, out, queueName, exchangeName, logFields)
+				s.runSubscriber(ctx, out, queueName, logFields)
 			case <-s.closing:
 				s.logger.Debug("Stopping ReconnectLoop (closing)", logFields)
 				break ReconnectLoop
@@ -199,17 +209,27 @@ func (s *Subscriber) SubscribeInitialize(topic string) (err error) {
 	exchangeName := s.config.Exchange.GenerateName(topic)
 	logFields["amqp_exchange_name"] = exchangeName
 
+	routingKey := s.config.QueueBind.GenerateRoutingKey(topic)
+	logFields["amqp_routing_key"] = routingKey
+
 	s.logger.Info("Initializing subscribe", logFields)
 
-	return errors.Wrap(s.prepareConsume(queueName, exchangeName, logFields), "failed to prepare consume")
+	params := BuildTopologyParams{
+		Topic:        topic,
+		QueueName:    queueName,
+		ExchangeName: exchangeName,
+		RoutingKey:   routingKey,
+	}
+
+	return errors.Wrap(s.prepareConsume(params, logFields), "failed to prepare consume")
 }
 
 // Close closes all subscriptions with their output channels.
 func (s *Subscriber) Close() error {
 	return s.closeSubscriber()
 }
 
-func (s *Subscriber) prepareConsume(queueName string, exchangeName string, logFields watermill.LogFields) (err error) {
+func (s *Subscriber) prepareConsume(params BuildTopologyParams, logFields watermill.LogFields) (err error) {
 	channel, err := s.openSubscribeChannel(logFields)
 	if err != nil {
 		return err
@@ -220,7 +240,7 @@ func (s *Subscriber) prepareConsume(queueName string, exchangeName string, logFi
 		}
 	}()
 
-	if err = s.config.TopologyBuilder.BuildTopology(channel, queueName, exchangeName, s.config, s.logger); err != nil {
+	if err = s.config.TopologyBuilder.BuildTopology(channel, params, s.config, s.logger); err != nil {
 		return err
 	}
 
@@ -233,7 +253,6 @@ func (s *Subscriber) runSubscriber(
 	ctx context.Context,
 	out chan *message.Message,
 	queueName string,
-	exchangeName string,
 	logFields watermill.LogFields,
 ) {
 	channel, err := s.openSubscribeChannel(logFields)