update builder to fix feature gate initialization

CHANGELOG.md

@@ -84,6 +84,10 @@
 - The `featuregates` were not configured from the "--feature-gates" flag on windows service (#5060)
 - Fix Semantic Convention Schema URL definition for 1.5.0 and 1.6.1 versions (#5103)
 
+### 🧰 Bug fixes 🧰
+
+- Fix the use of feature gates within factory initialization. (#4977)
+
 ## v0.47.0 Beta
 
 ### 🛑 Breaking changes 🛑

cmd/builder/internal/builder/templates/main.go.tmpl

@@ -8,32 +8,51 @@ package main
 import (
 	"log"
 
+	"github.com/spf13/cobra"
+
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/service"
+	"go.opentelemetry.io/collector/service/featuregate"
 )
 
 func main() {
-	factories, err := components()
-	if err != nil {
-		log.Fatalf("failed to build components: %v", err)
-	}
-
 	info := component.BuildInfo{
 		Command:     "{{ .Distribution.Name }}",
 		Description: "{{ .Distribution.Description }}",
 		Version:     "{{ .Distribution.Version }}",
 	}
 
-	if err := run(service.CollectorSettings{BuildInfo: info, Factories: factories}); err != nil {
-		log.Fatal(err)
+	if err := run(service.CollectorSettings{BuildInfo: info}); err != nil {
+		log.Fatalf("collector server run finished with error: %v", err)
 	}
 }
 
 func runInteractive(params service.CollectorSettings) error {
-	cmd := service.NewCommand(params)
-	if err := cmd.Execute(); err != nil {
-		log.Fatalf("collector server run finished with error: %v", err)
-	}
+	return newCommand(params).Execute()
+}
 
-	return nil
+func newCommand(params service.CollectorSettings) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:          params.BuildInfo.Command,
+		Version:      params.BuildInfo.Version,
+		SilenceUsage: true,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			featuregate.Apply(featuregate.GetFlags())
+			if params.ConfigProvider == nil {
+				params.ConfigProvider = service.MustNewDefaultConfigProvider(service.GetConfigFlag(), service.GetSetFlag())
+			}
+			var err error
+			params.Factories, err = components()
+			if err != nil {
+				return err
+			}
+			col, err := service.New(params)
+			if err != nil {
+				return err
+			}
+			return col.Run(cmd.Context())
+		},
+	}
+	cmd.Flags().AddGoFlagSet(service.Flags())
+	return cmd
 }

cmd/builder/internal/builder/templates/main_others.go.tmpl

@@ -8,5 +8,27 @@ package main
 import "go.opentelemetry.io/collector/service"
 
 func run(params service.CollectorSettings) error {
-	return runInteractive(params)
-}
+	cmd := &cobra.Command{
+		Use:          params.BuildInfo.Command,
+		Version:      params.BuildInfo.Version,
+		SilenceUsage: true,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			service.ApplyFeatureGateFlags()
+			if params.ConfigProvider == nil {
+				params.ConfigProvider = service.MustNewDefaultConfigProvider(service.GetConfigFlag(), service.GetSetFlag())
+			}
+			var err error
+			params.Factories, err = components()
+			if err != nil {
+				return err
+			}
+			col, err := service.New(params)
+			if err != nil {
+				return err
+			}
+			return col.Run(cmd.Context())
+		},
+	}
+	cmd.Flags().AddGoFlagSet(service.Flags())
+	return cmd.Execute()
+}

cmd/builder/internal/builder/templates/main_windows.go.tmpl

@@ -15,6 +15,11 @@ import (
 )
 
 func run(params service.CollectorSettings) error {
+	// Parse all the flags manually.
+	if err := service.Flags().Parse(os.Args[1:]); err != nil {
+		return err
+	}
+	service.ApplyFeatureGateFlags()
 	if useInteractiveMode, err := checkUseInteractiveMode(); err != nil {
 		return err
 	} else if useInteractiveMode {

cmd/otelcorecol/go.mod

@@ -5,6 +5,7 @@ module go.opentelemetry.io/collector/cmd/otelcorecol
 go 1.17
 
 require (
+	github.com/spf13/cobra v1.4.0
 	github.com/stretchr/testify v1.7.1
 	go.opentelemetry.io/collector v0.48.0
 	golang.org/x/sys v0.0.0-20220114195835-da31bd327af9
@@ -48,7 +49,6 @@ require (
 	github.com/rs/cors v1.8.2 // indirect
 	github.com/shirou/gopsutil/v3 v3.22.2 // indirect
 	github.com/spf13/cast v1.4.1 // indirect
-	github.com/spf13/cobra v1.4.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/tklauser/go-sysconf v0.3.9 // indirect
 	github.com/tklauser/numcpus v0.3.0 // indirect