feat(config): implement default configurations for common dependencies

Author: yarlson

pkg/config/config.go

@@ -100,28 +100,57 @@ type Dependency struct {
 	Container *Container `yaml:"container"`
 }
 
-// UnmarshalYAML is a custom unmarshaler that lets you handle both string and map forms.
+// getDefaultConfig retrieves a copy of the default config (if present),
+// then applies the provided version to the Image.
+func getDefaultConfig(baseName, version string) (*Dependency, bool) {
+	baseName = strings.ToLower(baseName)
+	dep, found := defaultConfigs[baseName]
+	if !found {
+		return nil, false
+	}
+	parts := strings.Split(dep.Image, ":")
+	if len(parts) == 2 {
+		dep.Image = parts[0] + ":" + version
+	} else {
+		dep.Image += ":" + version
+	}
+	return &dep, true
+}
+
+// UnmarshalYAML is a custom unmarshaler that lets you handle both string-based
+// and map-based dependencies.
 func (d *Dependency) UnmarshalYAML(node *yaml.Node) error {
 	switch node.Tag {
 	case "!!str":
 		// If the node is just a string (e.g. "postgres:16"), parse it.
-		// You can define your own logic here: how to set Name vs. Image, etc.
-		// For instance, if you want Name = the first part, and Image = the entire string:
 		value := node.Value
 		parts := strings.SplitN(value, ":", 2)
-		if len(parts) > 1 {
-			d.Name = parts[0]
-			d.Image = value // e.g. "postgres:16"
+
+		if len(parts) == 2 {
+			// We have a base name + version
+			base, version := parts[0], parts[1]
+			if defaultDep, ok := getDefaultConfig(base, version); ok {
+				*d = *defaultDep
+			} else {
+				// fallback for unknown base (e.g., "foobar:1.0")
+				d.Name = base
+				d.Image = value
+			}
 		} else {
-			// If there's no colon, define your fallback:
-			// e.g. "postgres" => use "postgres" for both Name and Image
-			d.Name = value
-			d.Image = value
+			// Only a base name (e.g., "redis")
+			base := parts[0]
+			if defaultDep, ok := getDefaultConfig(base, "latest"); ok {
+				*d = *defaultDep
+			} else {
+				// fallback for unknown base (e.g., "foobar")
+				d.Name = base
+				d.Image = base
+			}
 		}
 		return nil
 
 	case "!!map":
-		// If the node is a map, just decode into the struct in the usual way.
+		// If the node is a map, decode into the struct in the usual way.
 		type dependencyAlias Dependency
 		var tmp dependencyAlias
 		if err := node.Decode(&tmp); err != nil {

pkg/config/config_test.go

@@ -294,7 +294,7 @@ dependencies:
 	// Dependency #2: "redis"
 	// No colon, so we fall back to same name and image
 	assert.Equal(suite.T(), "redis", config.Dependencies[1].Name)
-	assert.Equal(suite.T(), "redis", config.Dependencies[1].Image)
+	assert.Equal(suite.T(), "redis:latest", config.Dependencies[1].Image)
 }
 
 func (suite *ConfigTestSuite) TestParseConfig_MixedDependencies() {
@@ -339,5 +339,5 @@ dependencies:
 	// Dependency #3: "elasticsearch" (no colon)
 	// We expect same name / image
 	assert.Equal(suite.T(), "elasticsearch", config.Dependencies[2].Name)
-	assert.Equal(suite.T(), "elasticsearch", config.Dependencies[2].Image)
+	assert.Equal(suite.T(), "elasticsearch:latest", config.Dependencies[2].Image)
 }

pkg/config/default_configs.go

@@ -0,0 +1,86 @@
+package config
+
+// defaultConfigs holds "base name" → default configuration
+// (image, ports, volumes, environment variables, container settings, etc.).
+var defaultConfigs = map[string]Dependency{
+	"mysql": {
+		Name:    "mysql",
+		Image:   "mysql:latest",
+		Ports:   []int{3306},
+		Volumes: []string{"mysql_data:/var/lib/mysql"},
+		Env: []string{
+			"MYSQL_ROOT_PASSWORD=production-secret",
+		},
+	},
+	"postgres": {
+		Name:    "postgres",
+		Image:   "postgres:latest",
+		Ports:   []int{5432},
+		Volumes: []string{"postgres_data:/var/lib/postgresql/data"},
+		Env: []string{
+			"POSTGRES_PASSWORD=production-secret",
+		},
+	},
+	"postgresql": {
+		Name:    "postgres",
+		Image:   "postgres:latest",
+		Ports:   []int{5432},
+		Volumes: []string{"postgres_data:/var/lib/postgresql/data"},
+		Env: []string{
+			"POSTGRES_PASSWORD=production-secret",
+		},
+	},
+	"elasticsearch": {
+		Name:    "elasticsearch",
+		Image:   "elasticsearch:latest",
+		Ports:   []int{9200, 9300},
+		Volumes: []string{"es_data:/usr/share/elasticsearch/data"},
+		Env: []string{
+			"discovery.type=single-node",
+		},
+		Container: &Container{
+			ULimits: []ULimit{
+				{
+					Name: "nofile",
+					Soft: 65535,
+					Hard: 65535,
+				},
+			},
+		},
+	},
+	"mongodb": {
+		Name:    "mongodb",
+		Image:   "mongo:latest",
+		Ports:   []int{27017},
+		Volumes: []string{"mongo_data:/data/db"},
+		Env: []string{
+			"MONGO_INITDB_ROOT_USERNAME=root",
+			"MONGO_INITDB_ROOT_PASSWORD=production-secret",
+		},
+	},
+	"redis": {
+		Name:    "redis",
+		Image:   "redis:latest",
+		Ports:   []int{6379},
+		Volumes: []string{"redis_data:/data"},
+	},
+	"memcached": {
+		Name:  "memcached",
+		Image: "memcached:latest",
+		Ports: []int{11211},
+	},
+	"rabbitmq": {
+		Name:  "rabbitmq",
+		Image: "rabbitmq:latest",
+		Ports: []int{5672, 15672}, // main + management
+		Container: &Container{
+			ULimits: []ULimit{
+				{
+					Name: "nofile",
+					Soft: 65535,
+					Hard: 65535,
+				},
+			},
+		},
+	},
+}