chore: initial commit

internal/pkg/messaging/kafka.go

@@ -0,0 +1,48 @@
+// Copyright (C) 2024 Declan Teevan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package messaging
+
+import (
+	"context"
+
+	"github.com/twmb/franz-go/pkg/kadm"
+	"github.com/twmb/franz-go/pkg/kgo"
+
+	"github.com/hexolan/stocklet/internal/pkg/config"
+	"github.com/hexolan/stocklet/internal/pkg/errors"
+)
+
+func NewKafkaConn(conf *config.KafkaConfig, opts ...kgo.Opt) (*kgo.Client, error) {
+	opts = append(opts, kgo.SeedBrokers(conf.Brokers...))
+	cl, err := kgo.NewClient(opts...)
+	if err != nil {
+		return nil, errors.WrapServiceError(errors.ErrCodeExtService, "failed to connect to Kafka", err)
+	}
+
+	return cl, nil
+}
+
+func EnsureKafkaTopics(cl *kgo.Client, topics ...string) error {
+	ctx := context.Background()
+	kadmCl := kadm.NewClient(cl)
+
+	_, err := kadmCl.CreateTopics(ctx, -1, -1, nil, topics...)
+	if err != nil {
+		return errors.WrapServiceError(errors.ErrCodeExtService, "failed to create Kafka topics", err)
+	}
+
+	return nil
+}

internal/pkg/messaging/messaging.go

@@ -0,0 +1,93 @@
+// Copyright (C) 2024 Declan Teevan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package messaging
+
+import (
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type ConsumerController interface {
+	Start()
+	Stop()
+}
+
+// Topic Definitions
+const (
+	// Order Topics
+	Order_State_Topic          = "order.state"
+	Order_State_Created_Topic  = Order_State_Topic + ".created"
+	Order_State_Pending_Topic  = Order_State_Topic + ".pending"
+	Order_State_Rejected_Topic = Order_State_Topic + ".rejected"
+	Order_State_Approved_Topic = Order_State_Topic + ".approved"
+
+	// Payment Topics
+	Payment_Balance_Topic          = "payment.balance"
+	Payment_Balance_Created_Topic  = Payment_Balance_Topic + ".created"
+	Payment_Balance_Credited_Topic = Payment_Balance_Topic + ".credited"
+	Payment_Balance_Debited_Topic  = Payment_Balance_Topic + ".debited"
+	Payment_Balance_Closed_Topic   = Payment_Balance_Topic + ".closed"
+
+	Payment_Transaction_Topic          = "payment.transaction"
+	Payment_Transaction_Created_Topic  = Payment_Transaction_Topic + ".created"
+	Payment_Transaction_Reversed_Topic = Payment_Transaction_Topic + ".reversed"
+
+	Payment_Processing_Topic = "payment.processing"
+
+	// Product Topics
+	Product_State_Topic         = "product.state"
+	Product_State_Created_Topic = Product_State_Topic + ".created"
+	Product_State_Deleted_Topic = Product_State_Topic + ".deleted"
+
+	Product_Attribute_Topic       = "product.attr"
+	Product_Attribute_Price_Topic = Product_Attribute_Topic + ".price"
+
+	Product_PriceQuotation_Topic = "product.pricequotation"
+
+	// Shipping Topics
+	Shipping_Shipment_Topic            = "shipping.shipment"
+	Shipping_Shipment_Allocation_Topic = Shipping_Shipment_Topic + ".allocation"
+	Shipping_Shipment_Dispatched_Topic = Shipping_Shipment_Topic + ".dispatched"
+
+	// User Topics
+	User_State_Topic         = "user.state"
+	User_State_Created_Topic = User_State_Topic + ".created"
+	User_State_Deleted_Topic = User_State_Topic + ".deleted"
+
+	User_Attribute_Topic       = "user.attr"
+	User_Attribute_Email_Topic = User_Attribute_Topic + ".email"
+
+	// Warehouse Topics
+	Warehouse_Stock_Topic         = "warehouse.stock"
+	Warehouse_Stock_Created_Topic = Warehouse_Stock_Topic + ".created"
+	Warehouse_Stock_Added_Topic   = Warehouse_Stock_Topic + ".added"
+	Warehouse_Stock_Removed_Topic = Warehouse_Stock_Topic + ".removed"
+
+	Warehouse_Reservation_Topic          = "warehouse.reservation"
+	Warehouse_Reservation_Failed_Topic   = Warehouse_Reservation_Topic + ".failed"
+	Warehouse_Reservation_Reserved_Topic = Warehouse_Reservation_Topic + ".reserved"
+	Warehouse_Reservation_Returned_Topic = Warehouse_Reservation_Topic + ".returned"
+	Warehouse_Reservation_Consumed_Topic = Warehouse_Reservation_Topic + ".consumed"
+)
+
+func MarshalEvent(event protoreflect.ProtoMessage, topic string) ([]byte, string, error) {
+	wireEvent, err := proto.Marshal(event)
+	if err != nil {
+		return []byte{}, "", err
+	}
+
+	return wireEvent, topic, nil
+}