Move CLI code to its own file

cli.go

@@ -0,0 +1,98 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/oklog/run"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+func newCLI() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "rekor-sidekick",
+		Short: "Transparency log monitoring and alerting",
+		Run:   runCLI,
+	}
+	cmd.Flags().String("config", "/etc/rekor-sidekick/config.yaml", "Path to configuration file")
+	return cmd
+}
+
+func runCLI(cmd *cobra.Command, args []string) {
+	if err := viper.BindPFlags(cmd.Flags()); err != nil {
+		fmt.Println("Failed to bind command line flags to viper:", err)
+		os.Exit(1)
+	}
+
+	// Environment variable setup
+	viper.SetEnvPrefix(`REKOR_SIDEKICK`)
+	viper.AutomaticEnv()
+
+	// Load config file
+	{
+		f, err := os.Open(viper.GetString("config"))
+		if err != nil {
+			fmt.Println("Failed to open config file:", err)
+			os.Exit(1)
+		}
+		defer f.Close()
+
+		viper.SetConfigType("yaml")
+		if err := viper.ReadConfig(f); err != nil {
+			fmt.Println("Failed to parse config:", err)
+			os.Exit(1)
+		}
+	}
+
+	var c config
+	if err := viper.Unmarshal(&c); err != nil {
+		fmt.Println("Failed to load configuration:", err)
+		os.Exit(1)
+	}
+
+	a, err := newAgent(c)
+	if err != nil {
+		fmt.Println("Failed to initialize agent:", err)
+		os.Exit(1)
+	}
+
+	// This run group manages all the concurrent processes
+	// this command runs. That is the agent and a signal handler
+	// at the moment.
+	var g run.Group
+
+	// Agent process
+	g.Add(a.run, func(error) {
+		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+		defer cancel()
+		a.shutdown(ctx)
+	})
+
+	// Signal handler process
+	{
+		ctx, cancel := context.WithCancel(context.Background())
+		g.Add(func() error {
+			c := make(chan os.Signal, 1)
+			signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
+			select {
+			case sig := <-c:
+				return fmt.Errorf("received signal %s", sig)
+			case <-ctx.Done():
+				return ctx.Err()
+			}
+		}, func(error) {
+			cancel()
+		})
+	}
+
+	// Launch!
+	if err = g.Run(); err != nil {
+		log.Println(err)
+	}
+}

main.go

@@ -1,103 +1,5 @@
 package main
 
-import (
-	"context"
-	"fmt"
-	"log"
-	"os"
-	"os/signal"
-	"syscall"
-	"time"
-
-	"github.com/oklog/run"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-func newCLI() *cobra.Command {
-	cmd := &cobra.Command{
-		Use:   "rekor-sidekick",
-		Short: "Transparency log monitoring and alerting",
-		Run:   runCLI,
-	}
-	cmd.Flags().String("config", "/etc/rekor-sidekick/config.yaml", "Path to configuration file")
-	return cmd
-}
-
-func runCLI(cmd *cobra.Command, args []string) {
-	if err := viper.BindPFlags(cmd.Flags()); err != nil {
-		fmt.Println("Failed to bind command line flags to viper:", err)
-		os.Exit(1)
-	}
-
-	// Environment variable setup
-	viper.SetEnvPrefix(`REKOR_SIDEKICK`)
-	viper.AutomaticEnv()
-
-	// Load config file
-	{
-		f, err := os.Open(viper.GetString("config"))
-		if err != nil {
-			fmt.Println("Failed to open config file:", err)
-			os.Exit(1)
-		}
-		defer f.Close()
-
-		viper.SetConfigType("yaml")
-		if err := viper.ReadConfig(f); err != nil {
-			fmt.Println("Failed to parse config:", err)
-			os.Exit(1)
-		}
-	}
-
-	var c config
-	if err := viper.Unmarshal(&c); err != nil {
-		fmt.Println("Failed to load configuration:", err)
-		os.Exit(1)
-	}
-
-	a, err := newAgent(c)
-	if err != nil {
-		fmt.Println("Failed to initialize agent:", err)
-		os.Exit(1)
-	}
-
-	// This run group manages all the concurrent processes
-	// this command runs. That is the agent and a signal handler
-	// at the moment.
-	var g run.Group
-
-	// Agent process
-	g.Add(a.run, func(error) {
-		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
-		defer cancel()
-		a.shutdown(ctx)
-	})
-
-	// Signal handler process
-	{
-		ctx, cancel := context.WithCancel(context.Background())
-		g.Add(func() error {
-			c := make(chan os.Signal, 1)
-			signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
-			select {
-			case sig := <-c:
-				return fmt.Errorf("received signal %s", sig)
-			case <-ctx.Done():
-				return ctx.Err()
-			}
-		}, func(error) {
-			cancel()
-		})
-	}
-
-	// Launch!
-	if err = g.Run(); err != nil {
-		log.Println(err)
-	}
-
-}
-
 func main() {
 	cmd := newCLI()
 	cmd.Execute()