initial commit

infrastructure/rabbitmq/publisher.go

@@ -0,0 +1,89 @@
+package rabbitmq
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+
+	"github.com/wagslane/go-rabbitmq"
+
+	"code.icb4dc0.de/prskr/pg_v_man/core/domain"
+	"code.icb4dc0.de/prskr/pg_v_man/core/ports"
+	"code.icb4dc0.de/prskr/pg_v_man/infrastructure/config"
+)
+
+var _ ports.ReplicationEventConsumer = (*PublishingEventConsumer)(nil)
+
+func NewPublishingEventConsumer(ctx context.Context, cfg config.RabbitMQ) (consumer *PublishingEventConsumer, err error) {
+	var dialer net.Dialer
+	conn, err := rabbitmq.NewConn(cfg.ConnectionString, rabbitmq.WithConnectionOptionsLogging, func(options *rabbitmq.ConnectionOptions) {
+		options.Config.Dial = func(network, addr string) (net.Conn, error) {
+			return dialer.DialContext(ctx, network, addr)
+		}
+	})
+	if err != nil {
+		return nil, fmt.Errorf("could not create RabbitMQ connection: %w", err)
+	}
+
+	defer func() {
+		if err != nil {
+			err = errors.Join(err, conn.Close())
+		}
+	}()
+
+	publisherOptions := []func(*rabbitmq.PublisherOptions){
+		rabbitmq.WithPublisherOptionsLogging,
+		rabbitmq.WithPublisherOptionsExchangeName(cfg.Exchange.Name),
+		rabbitmq.WithPublisherOptionsExchangeKind(cfg.Exchange.Kind),
+		rabbitmq.WithPublisherOptionsExchangeDeclare,
+	}
+
+	if cfg.Exchange.Durable {
+		publisherOptions = append(publisherOptions, rabbitmq.WithPublisherOptionsExchangeDurable)
+	}
+
+	publisher, err := rabbitmq.NewPublisher(
+		conn,
+		publisherOptions...,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("could not create RabbitMQ publisher: %w", err)
+	}
+
+	return &PublishingEventConsumer{Conn: conn, Publisher: publisher, Cfg: cfg}, nil
+}
+
+type PublishingEventConsumer struct {
+	Conn      *rabbitmq.Conn
+	Publisher *rabbitmq.Publisher
+	Cfg       config.RabbitMQ
+}
+
+func (p PublishingEventConsumer) OnDataChange(ctx context.Context, ev domain.ReplicationEvent) error {
+	data, err := json.Marshal(ev)
+	if err != nil {
+		return fmt.Errorf("could not marshal event: %w", err)
+	}
+	return p.Publisher.PublishWithContext(
+		ctx, data, []string{p.Cfg.RoutingKey, strings.Join([]string{ev.DBName, ev.Namespace, ev.Relation}, ".")},
+		rabbitmq.WithPublishOptionsContentType("application/json"),
+		rabbitmq.WithPublishOptionsExchange(p.Cfg.Exchange.Name),
+		rabbitmq.WithPublishOptionsCorrelationID(strconv.Itoa(int(ev.TransactionId))),
+		rabbitmq.WithPublishOptionsType(ev.EventType.String()),
+		rabbitmq.WithPublishOptionsHeaders(rabbitmq.Table{
+			"db":        ev.DBName,
+			"namespace": ev.Namespace,
+			"relation":  ev.Relation,
+		}),
+	)
+}
+
+func (p PublishingEventConsumer) Close() error {
+	p.Publisher.Close()
+
+	return p.Conn.Close()
+}