Add the example

Signed-off-by: Gabriele Santomaggio <G.santomaggio@gmail.com>

Author: Gsantomaggio

docs/examples/README.md

@@ -12,4 +12,5 @@
 - [Broadcast](broadcast) - An example of how to use fanout to broadcast messages to multiple auto-deleted queues.
 - [RPC Echo](rpc_echo_server) - An example of how to implement RPC with the AMQP 1.0 client.
 - [SQL stream Filtering](sql_stream_filter) - An example of how to use SQL stream filtering with RabbitMQ Streams.
-- [Web Sockets](web_sockets) - An example of how to use Web Sockets with the AMQP 1.0 client.
+- [Web Sockets](web_sockets) - An example of how to use Web Sockets with the AMQP 1.0 client.
+- [Pre-settled messages](pre_settled) - An example of how to receive pre-settled messages with the AMQP 1.0 client.

docs/examples/pre_settled/pre_settled.go

@@ -0,0 +1,103 @@
+// RabbitMQ AMQP 1.0 Go Client: https://github.com/rabbitmq/rabbitmq-amqp-go-client
+// RabbitMQ AMQP 1.0 documentation: https://www.rabbitmq.com/docs/amqp
+// This example is demonstrating how to consume messages with pre-settled mode enabled.
+// pre-settled is valid only for classic and quorum queues.
+// Pre-settled mode means that messages are considered accepted by the broker as soon as they are delivered to the consumer,
+// without requiring explicit acceptance from the consumer side.
+// This is useful for scenarios where at-most-once delivery semantics are acceptable, and it can improve performance by reducing
+// the overhead of message acknowledgments.
+// Example path:https://github.com/rabbitmq/rabbitmq-amqp-go-client/tree/main/docs/examples/pre_settled/pre_settled.go
+package main
+
+import (
+	"context"
+	"fmt"
+
+	rmq "github.com/rabbitmq/rabbitmq-amqp-go-client/pkg/rabbitmqamqp"
+)
+
+func main() {
+	rmq.Info("Pre-Settled example with AMQP Go AMQP 1.0 Client")
+
+	env := rmq.NewEnvironment("amqp://guest:guest@localhost:5672/", nil)
+	amqpConnection, err := env.NewConnection(context.Background())
+	if err != nil {
+		rmq.Error("Error opening connection", err)
+		return
+	}
+	// create queue for the example
+	_, err = amqpConnection.Management().DeclareQueue(context.TODO(), &rmq.QuorumQueueSpecification{
+		Name: "pre-settled-queue",
+	})
+	if err != nil {
+		rmq.Error("Error declaring queue", err)
+		return
+	}
+	rmq.Info("Queue 'pre-settled-queue' declared")
+
+	// publish some messages to the queue
+	producer, err := amqpConnection.NewPublisher(context.TODO(), &rmq.QueueAddress{
+		Queue: "pre-settled-queue",
+	}, nil)
+	if err != nil {
+		rmq.Error("Error creating producer", err)
+		return
+	}
+	for i := 0; i < 100; i++ {
+		msg := rmq.NewMessage([]byte(fmt.Sprintf("Pre-settled message number %d ", i+1)))
+		_, err := producer.Publish(context.TODO(), msg)
+		if err != nil {
+			rmq.Error("Error publishing message", err)
+			return
+		}
+	}
+
+	// create consumer with pre-settled mode enabled
+
+	consumer, err := amqpConnection.NewConsumer(context.TODO(), "pre-settled-queue", &rmq.ConsumerOptions{
+		PreSettled: true,
+	})
+	if err != nil {
+		rmq.Error("Error creating consumer", err)
+		return
+	}
+	rmq.Info("Consumer created with pre-settled mode enabled")
+
+	for i := 0; i < 100; i++ {
+		dc, err := consumer.Receive(context.TODO())
+		if err != nil {
+			rmq.Error("Error consuming message", err)
+			return
+		}
+		// here we don't need to accept the message
+		// because pre-settled mode is enabled
+		rmq.Info("[Consumer]", "Message received", string(dc.Message().GetData()))
+	}
+
+	// clean up
+	err = consumer.Close(context.TODO())
+	if err != nil {
+		rmq.Error("Error closing consumer", err)
+		return
+	}
+	err = producer.Close(context.TODO())
+	if err != nil {
+		rmq.Error("Error closing producer", err)
+		return
+	}
+	// delete the queue
+	err = amqpConnection.Management().DeleteQueue(context.TODO(), "pre-settled-queue")
+	if err != nil {
+		rmq.Error("Error deleting queue", err)
+		return
+	}
+	rmq.Info("Queue 'pre-settled-queue' deleted")
+
+	err = amqpConnection.Close(context.TODO())
+	if err != nil {
+		rmq.Error("Error closing connection", err)
+		return
+	}
+	rmq.Info("Example finished successfully")
+
+}

pkg/rabbitmqamqp/amqp_types.go

@@ -54,9 +54,7 @@ type IConsumerOptions interface {
 	// preSettled indicates if the consumer should use pre-settled delivery mode.
 	// When enabled, messages arrive already settled from the broker, which makes
 	// settlement from the client with a disposition frame not necessary.
-	// This is the "fire-and-forget" or "at-most-once" mode. It should be faster
-	// but may result in message loss. It is fine for use cases like log streaming
-	// or sensor telemetry.
+	// This is the "fire-and-forget" or "at-most-once" mode.
 	preSettled() bool
 }