refactor: added default plugins and check before loading

pkg/generator/generator.go

@@ -14,14 +14,15 @@ import (
 	"github.com/nikolalohinski/gonja/v2/exec"
 )
 
-type Mappings map[string]any
-type FileMap map[string][]byte
-type FileList [][]byte
-type Template []byte
+type (
+	Mappings map[string]any
+	FileMap  map[string][]byte
+	FileList [][]byte
+	Template []byte
 
 	// Generator interface used to define how files are created. Plugins can
 	// be created entirely independent of the main driver program.
-type Generator interface {
+	Generator interface {
 		GetName() string
 		GetVersion() string
 		GetDescription() string
@@ -29,14 +30,30 @@ type Generator interface {
 	}
 
 	// Params defined and used by the "generate" subcommand.
-type Params struct {
+	Params struct {
 		Args          []string
-	Generators    map[string]Generator
 		TemplatePaths []string
 		PluginPath    string
 		Target        string
 		Verbose       bool
 	}
+)
+
+var DefaultGenerators = createDefaultGenerators()
+
+func createDefaultGenerators() map[string]Generator {
+	var (
+		generatorMap = map[string]Generator{}
+		generators   = []Generator{
+			&Conman{}, &DHCPd{}, &DNSMasq{}, &Hostfile{},
+			&Powerman{}, &Syslog{}, &Warewulf{},
+		}
+	)
+	for _, g := range generators {
+		generatorMap[g.GetName()] = g
+	}
+	return generatorMap
+}
 
 // Converts the file outputs from map[string][]byte to map[string]string.
 func ConvertContentsToString(f FileMap) map[string]string {
@@ -397,6 +414,10 @@ func GenerateWithTarget(config *configurator.Config, params Params) (FileMap, er
 			configurator.WithAccessToken(config.AccessToken),
 			configurator.WithCertPoolFile(config.CertPath),
 		)
+		target    configurator.Target
+		generator Generator
+		err       error
+		ok        bool
 	)
 
 	// check if a target is supplied
@@ -405,7 +426,7 @@ func GenerateWithTarget(config *configurator.Config, params Params) (FileMap, er
 	}
 
 	// load target information from config
-	target, ok := config.Targets[params.Target]
+	target, ok = config.Targets[params.Target]
 	if !ok {
 		return nil, fmt.Errorf("target not found in config")
 	}
@@ -415,11 +436,15 @@ func GenerateWithTarget(config *configurator.Config, params Params) (FileMap, er
 		target.PluginPath = params.PluginPath
 	}
 
-	// only load the plugin needed for this target
-	generator, err := LoadPlugin(target.PluginPath)
+	// check if generator is built-in first before loading
+	generator, ok = DefaultGenerators[params.Target]
+	if !ok {
+		// only load the plugin needed for this target if we don't find default
+		generator, err = LoadPlugin(target.PluginPath)
 		if err != nil {
 			return nil, fmt.Errorf("failed to load plugin: %w", err)
 		}
+	}
 
 	// run the generator plugin from target passed
 	return generator.Generate(