Feature/keycloak auth configuration

.gitignore

@@ -28,3 +28,4 @@
 go.work
 
 # End of https://www.toptal.com/developers/gitignore/api/go,dotenv
+.gocache

README.md

@@ -6,7 +6,9 @@ It uses **PostgreSQL** as the database, **RabbitMQ** for asynchronous communicat
 ## 🚀 Features
 
 - Management of **companies** (`companies`)
-- Management of **users** (`users`)
+- Management of **users** (`users-company`)
+- Lookup of company users by **Keycloak ID**
+- Global **CORS** support with `OPTIONS` preflight handling
 - Publishing RabbitMQ events (`CompanyCreated`, `UserCreated`)
 - Modular and extensible microservice architecture
 - Persistence via PostgreSQL
@@ -19,10 +21,13 @@ It uses **PostgreSQL** as the database, **RabbitMQ** for asynchronous communicat
 ├── config/
 │   └── config.go       # Configuration & env loading
 ├── internal/
-│   ├── customer/
-│   │ ├── company/      # "Company" business logic
-│   │ └── user/         # "User" business logic
+│   ├── company/        # "Company" business logic
+│   ├── user/           # "User" business logic
 │   └── event/          # RabbitMQ publishing
+├── docs/
+│   ├── API.md          # Route-by-route API reference
+│   └── available-keycloak-users-contract.md
+│                      # Proposed dropdown contract for frontend integration
 ├── routes/
 │   └── route.go        # Application routes
 ├── docker-compose.yml  # Full stack (Go + Postgres + RabbitMQ)
@@ -45,6 +50,8 @@ Create a `.env` file at the root of the project and fill in the variables:
 cp .env.example .env
 ```
 
+The service only needs database and RabbitMQ configuration from `.env`.
+
 ## 🐳 Running the project
 
 From the root of the project:
@@ -57,31 +64,62 @@ docker compose up --build
 
 📋 API (via Postman, curl, etc.)
 
-| Method | Endpoint               | Description                       |
-| ------ | ---------------------- | --------------------------------- |
-| POST   | `/companies`           | Create a company                  |
-| GET    | `/companies/:id`       | Retrieve a company                |
-| POST   | `/companies/:id/users` | Create a user linked to a company |
-| GET    | `/users/:id`           | Retrieve a user                   |
+| Method | Endpoint | Description |
+| ------ | -------- | ----------- |
+| GET | `/health` | Health check |
+| POST | `/companies` | Create a company |
+| GET | `/companies` | List companies |
+| GET | `/companies/:id` | Retrieve a company |
+| PUT | `/companies/:id` | Update a company |
+| DELETE | `/companies/:id` | Delete a company |
+| POST | `/companies/:id/users-company` | Create a user linked to a company |
+| GET | `/companies/:id/users-company` | List users linked to a company |
+| GET | `/users-company/keycloak/:keycloak_id` | Retrieve a user by Keycloak ID |
+| GET | `/users-company/keycloak/:keycloak_id/role` | Retrieve only the user role by Keycloak ID |
+| GET | `/users-company/keycloak/:keycloak_id/company-id` | Retrieve only the company ID by Keycloak ID |
+| GET | `/users-company/:id` | Retrieve a user |
+| PUT | `/users-company/:id` | Update a user |
+| DELETE | `/users-company/:id` | Delete a user |
+
+Full route-by-route documentation with direct URLs and `curl` examples is available in [`docs/API.md`](docs/API.md).
+
+The proposed backend contract for the frontend "available Keycloak users" dropdown is documented in [`docs/available-keycloak-users-contract.md`](docs/available-keycloak-users-contract.md).
+
+## 🌐 CORS
 
-> Sample CURLs are available in each resource-specific `repository`.
+The API exposes global CORS headers for browser clients:
+
+- `Access-Control-Allow-Origin: *`
+- `Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS`
+- `Access-Control-Allow-Headers: Origin, Content-Type, Accept, Authorization`
+- `OPTIONS` preflight requests return `204 No Content`
 
 ## 🗄️ Accessing PostgreSQL
 
 From your terminal:
 
 ```bash
-psql -h localhost -p 5433 -U user -d customers
+psql -h localhost -p 5434 -U user -d customer_service_db
 ```
 
 Then:
 
 ```sql
 \dt -- List tables
 SELECT * FROM companies;
-SELECT * FROM users;
+SELECT * FROM user_companies;
 ```
 
+## Create User
+Please run this create for adding your keycloak account to an admin account.
+```bash
+curl -X POST http://localhost:8080/companies/1/users-company \
+  -H "Content-Type: application/json" \
+  -d '{
+    "id_auth_kc": "08d697a6-8b89-40fc-aaf3-bdaaa65e0ae4",
+    "role": "admin"
+  }'
+```
 ## 🧹 Cleanup
 
 To stop and remove containers:

cmd/main.go

@@ -18,7 +18,10 @@ import (
 )
 
 func main() {
-	cfg := config.LoadConfig()
+	cfg, err := config.LoadConfig()
+	if err != nil {
+		log.Fatal("Invalid configuration:", err)
+	}
 
 	// PostgreSQL connection
 	log.Println("Connecting to Postgres with DSN:", cfg.PostgresDSN())
@@ -76,6 +79,7 @@ func main() {
 
 	// Router
 	r := gin.Default()
+	r.Use(routes.WithConfig(cfg), routes.CORSMiddleware())
 
 	// Fetch trusted proxies from .env
 	proxies := os.Getenv("TRUSTED_PROXIES")

config/config.go

@@ -2,8 +2,8 @@ package config
 
 import (
 	"fmt"
-	"log"
 	"os"
+	"strings"
 )
 
 type Config struct {
@@ -14,7 +14,7 @@ type Config struct {
 	RabbitMQ   string
 }
 
-func LoadConfig() *Config {
+func LoadConfig() (*Config, error) {
 	cfg := &Config{
 		DBHost:     os.Getenv("DB_HOST"),
 		DBUser:     os.Getenv("DB_USER"),
@@ -23,11 +23,29 @@ func LoadConfig() *Config {
 		RabbitMQ:   os.Getenv("RABBITMQ_HOST"),
 	}
 
-	if cfg.DBHost == "" || cfg.DBUser == "" || cfg.DBPassword == "" || cfg.DBName == "" || cfg.RabbitMQ == "" {
-		log.Fatal("Missing required environment variables")
+	var missing []string
+	requiredValues := []struct {
+		name  string
+		value string
+	}{
+		{name: "DB_HOST", value: cfg.DBHost},
+		{name: "DB_USER", value: cfg.DBUser},
+		{name: "DB_PASSWORD", value: cfg.DBPassword},
+		{name: "DB_NAME", value: cfg.DBName},
+		{name: "RABBITMQ_HOST", value: cfg.RabbitMQ},
 	}
 
-	return cfg
+	for _, item := range requiredValues {
+		if item.value == "" {
+			missing = append(missing, item.name)
+		}
+	}
+
+	if len(missing) > 0 {
+		return nil, fmt.Errorf("missing required environment variables: %s", strings.Join(missing, ", "))
+	}
+
+	return cfg, nil
 }
 
 func (c *Config) PostgresDSN() string {

config/config_test.go

@@ -0,0 +1,39 @@
+package config
+
+import (
+	"strings"
+	"testing"
+)
+
+func setRequiredEnv(t *testing.T) {
+	t.Helper()
+
+	t.Setenv("DB_HOST", "localhost")
+	t.Setenv("DB_USER", "user")
+	t.Setenv("DB_PASSWORD", "secret")
+	t.Setenv("DB_NAME", "customer_service_db")
+	t.Setenv("RABBITMQ_HOST", "rabbitmq")
+}
+
+func TestLoadConfig_Success(t *testing.T) {
+	setRequiredEnv(t)
+
+	_, err := LoadConfig()
+	if err != nil {
+		t.Fatalf("LoadConfig returned error: %v", err)
+	}
+}
+
+func TestLoadConfig_MissingRequiredEnv(t *testing.T) {
+	setRequiredEnv(t)
+	t.Setenv("RABBITMQ_HOST", "")
+
+	_, err := LoadConfig()
+	if err == nil {
+		t.Fatal("expected LoadConfig to fail when a required env var is missing")
+	}
+
+	if !strings.Contains(err.Error(), "RABBITMQ_HOST") {
+		t.Fatalf("expected error to mention RABBITMQ_HOST, got %v", err)
+	}
+}

docker-compose.yml

@@ -5,11 +5,11 @@ services:
     env_file:
       - .env
     ports:
-      - "5433:5432"
+      - "5434:5432"
     volumes:
       - ./scripts:/docker-entrypoint-initdb.d
     healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U $POSTGRES_USER"]
+      test: ["CMD-SHELL", "pg_isready -U $POSTGRES_USER -d $POSTGRES_DB"]
       interval: 5s
       timeout: 5s
       retries: 5