cmd: pass context through args

as suggested in [#360], we should be closer to idiomatic go where rather
than passing context via structs, we make use of 1st-arg for ctx.

see https://pkg.go.dev/context for more details

[#360]: #360 (comment)

Signed-off-by: Ciro S. Costa <ciroscosta@vmware.com>

cmd/cartographer/main.go

@@ -40,7 +40,6 @@ func init() {
 
 func main() {
 	ctx, cancel := context.WithCancel(context.Background())
-
 	defer cancel()
 
 	loggerOpt, err := logger.SetLogLevel(verbosity)
@@ -51,11 +50,10 @@ func main() {
 	cmd := root.Command{
 		Port:    port,
 		CertDir: certDir,
-		Context: ctx,
 		Logger:  zap.New(zap.UseDevMode(devMode), loggerOpt),
 	}
 
-	if err = cmd.Execute(); err != nil {
+	if err = cmd.Execute(ctx); err != nil {
 		panic(err)
 	}
 }

pkg/registrar/registrar.go

@@ -312,7 +312,7 @@ func registerRunnableController(mgr manager.Manager) error {
 	return nil
 }
 
-func IndexResources(mgr manager.Manager, ctx context.Context) error {
+func IndexResources(ctx context.Context, mgr manager.Manager) error {
 	fieldIndexer := mgr.GetFieldIndexer()
 
 	if err := indexSupplyChains(ctx, fieldIndexer); err != nil {

pkg/root/root.go

@@ -32,11 +32,10 @@ import (
 type Command struct {
 	Port    int
 	CertDir string
-	Context context.Context
 	Logger  logr.Logger
 }
 
-func (cmd *Command) Execute() error {
+func (cmd *Command) Execute(ctx context.Context) error {
 	log.SetLogger(cmd.Logger)
 	l := log.Log.WithName("cartographer")
 
@@ -65,7 +64,7 @@ func (cmd *Command) Execute() error {
 		return fmt.Errorf("register controllers: %w", err)
 	}
 
-	if err := registrar.IndexResources(mgr, cmd.Context); err != nil {
+	if err := registrar.IndexResources(ctx, mgr); err != nil {
 		return fmt.Errorf("index resources: %w", err)
 	}
 
@@ -109,7 +108,7 @@ func (cmd *Command) Execute() error {
 		}
 	}
 
-	if err := mgr.Start(cmd.Context); err != nil {
+	if err := mgr.Start(ctx); err != nil {
 		return fmt.Errorf("manager start: %w", err)
 	}