Software Architecture in Go: Extensibility - Part 5

Enable build tags and docker args to support Redis.

https://youtu.be/Wb24mcqNGD4

.github/workflows/ci.yml

@@ -10,10 +10,11 @@ jobs:
         uses: actions/setup-go@v5
         with:
           go-version: 1.23.x
+          check-latest: true
           cache: true
           cache-dependency-path: |
             **/go.sum
-            internal/tool/go.sum
+            internal/tools/go.sum
       - name: Lint
         run: make lint
       - name: Make Docker images

.golangci.yml

@@ -52,8 +52,6 @@ linters-settings:
     ignorePackageGlobs:
       - github.com/MarioCarrion/todo-api/*
 issues:
-  exclude:
-    - "NewMessageBrokerPublisher redeclared in this block" # build tags: `redis`, `rabbitmq` or `kafka`
   exclude-rules:
     # All tests
     - path: _test\.go

Makefile

@@ -68,3 +68,4 @@ test:
 docker:
 	docker compose -f compose.yml -f compose.kafka.yml build
 	docker compose -f compose.yml -f compose.rabbitmq.yml build
+	docker compose -f compose.yml -f compose.redis.yml build

README.md

@@ -120,13 +120,14 @@ In no particular order:
 
 ## Running project locally using Docker Compose
 
-Originally added as part of [Building Microservices In Go: Containerization with Docker](https://youtu.be/u_ayzie9pAQ), `docker compose` has evolved and with it the way to run everything locally. Make sure you are running a recent version of Docker Compose. The configuration in this repository and the instructions below are known to work:
+Originally added as part of [Building Microservices In Go: Containerization with Docker](https://youtu.be/u_ayzie9pAQ), `docker compose` has evolved and with it the way to run everything locally. Make sure you are running a recent version of Docker Compose. The configuration in this repository and the instructions below are known to work for at least the following versions:
 
 * Engine: **27.4.0**, and
 * Compose: **v2.31.0-desktop.2**
 
-This project takes advantage of [Go's build constrains](https://pkg.go.dev/go/build) and [Docker's arguments](https://docs.docker.com/reference/dockerfile/#arg) to build and run the [rest-server](cmd/rest-server) using any of the following types of message broker:
+This project takes advantage of [Go's build constrains](https://pkg.go.dev/go/build) and [Docker's arguments](https://docs.docker.com/reference/dockerfile/#arg) to build the ElasticSearch indexers and to run the [rest-server](cmd/rest-server) using any of the following types of message broker:
 
+* Redis (**default one**)
 * RabbitMQ
 * Kafka
 
@@ -138,22 +139,25 @@ docker compose -f compose.yml -f compose.<type>.yml <command>
 
 Where:
 
-* `<type>`: Indicates what message broker to use. Currently there are two supported values: `rabbitmq` and `kafka`; those effectively match the compose filename itself.
+* `<type>`: Indicates what message broker to use, and effectively match the compose filename itself. The three supported values are:
+    1. `rabbitmq`,
+    1. `kafka`, and
+    1. `redis` (default value when building the `rest-server` binary).
 * `<command>`: Indicates the docker compose command to use.
 
-For example to build images using RabbitMQ as the message broker you would do:
+For example to build images using RabbitMQ as the message broker you execute:
 
 ```
 docker compose -f compose.yml -f compose.rabbitmq.yml build
 ```
 
-Then to start the containers you would do:
+Then to start the containers you execute:
 
 ```
 docker compose -f compose.yml -f compose.rabbitmq.yml up
 ```
 
-Once you `up` all the containers you can access the Swagger UI at http://127.0.0.1:9234/static/swagger-ui/ .
+Once you all the containers are `up` you can access the Swagger UI at http://127.0.0.1:9234/static/swagger-ui/ .
 
 ## Diagrams
 

cmd/rest-server/kafka.go

@@ -1,4 +1,4 @@
-//go:build !rabbitmq
+//go:build kafka
 
 package main
 

cmd/rest-server/redis.go

@@ -0,0 +1,46 @@
+//go:build !kafka && !rabbitmq
+
+package main
+
+import (
+	"github.com/go-redis/redis/v8"
+
+	cmdinternal "github.com/MarioCarrion/todo-api/cmd/internal"
+	"github.com/MarioCarrion/todo-api/internal"
+	"github.com/MarioCarrion/todo-api/internal/envvar"
+	internalredis "github.com/MarioCarrion/todo-api/internal/redis"
+	"github.com/MarioCarrion/todo-api/internal/service"
+)
+
+// RedisMessageBroker represents Redis as a Message Broker.
+type RedisMessageBroker struct {
+	client    *redis.Client
+	publisher service.TaskMessageBrokerPublisher
+}
+
+// NewMessageBrokerPublisher initializes a new Redis Broker.
+func NewMessageBrokerPublisher(conf *envvar.Configuration) (MessageBrokerPublisher, error) { //nolint: ireturn
+	producer, err := cmdinternal.NewRedis(conf)
+	if err != nil {
+		return nil, internal.WrapErrorf(err, internal.ErrorCodeUnknown, "internal.NewRedis")
+	}
+
+	return &RedisMessageBroker{
+		client:    producer,
+		publisher: internalredis.NewTask(producer),
+	}, nil
+}
+
+// Publisher returns the Redis broker.
+func (m *RedisMessageBroker) Publisher() service.TaskMessageBrokerPublisher { //nolint: ireturn
+	return m.publisher
+}
+
+// Close closes the broker.
+func (m *RedisMessageBroker) Close() error {
+	if err := m.client.Close(); err != nil {
+		return internal.WrapErrorf(err, internal.ErrorCodeUnknown, "producer.Close")
+	}
+
+	return nil
+}

compose.redis.yml

@@ -0,0 +1,33 @@
+services:
+  rest-server-redis:
+    extends:
+      file: compose.common.yml
+      service: rest-server-common
+    build:
+      args:
+        TAG: redis
+    environment:
+      REDIS_HOST: redis:6379
+    depends_on:
+      redis:
+        condition: service_healthy
+  elasticsearch-indexer-redis:
+    extends:
+      file: compose.common.yml
+      service: elasticsearch-indexer-common
+    build:
+      dockerfile: ./dockerfiles/elasticsearch-indexer-redis.Dockerfile
+    environment:
+      REDIS_HOST: redis:6379
+    depends_on:
+      redis:
+        condition: service_healthy
+  redis:
+    image: redis:7.0.9-alpine3.17
+    ports:
+      - 6379:6379
+    healthcheck:
+      test: ["CMD-SHELL", "redis-cli ping || exit 1"]
+      interval: 20s
+      timeout: 1s
+      retries: 5