Use cobra for tools

tools/asynqmon/cmd/root.go

@@ -0,0 +1,76 @@
+package cmd
+
+import (
+	"fmt"
+	"github.com/spf13/cobra"
+	"os"
+
+	homedir "github.com/mitchellh/go-homedir"
+	"github.com/spf13/viper"
+)
+
+var cfgFile string
+
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
+	Use:   "asynqmon",
+	Short: "A monitoring tool for asynq queues",
+	Long: `TODO(hibiken): A longer description that spans multiple lines and likely contains
+examples and usage of using your application. For example:
+
+Cobra is a CLI library for Go that empowers applications.
+This application is a tool to generate the needed files
+to quickly create a Cobra application.`,
+	// Uncomment the following line if your bare application
+	// has an action associated with it:
+	//	Run: func(cmd *cobra.Command, args []string) { },
+}
+
+// Execute adds all child commands to the root command and sets flags appropriately.
+// This is called by main.main(). It only needs to happen once to the rootCmd.
+func Execute() {
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func init() {
+	cobra.OnInitialize(initConfig)
+
+	// Here you will define your flags and configuration settings.
+	// Cobra supports persistent flags, which, if defined here,
+	// will be global for your application.
+
+	rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.asynqmon.yaml)")
+
+	// Cobra also supports local flags, which will only run
+	// when this action is called directly.
+	rootCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+}
+
+// initConfig reads in config file and ENV variables if set.
+func initConfig() {
+	if cfgFile != "" {
+		// Use config file from the flag.
+		viper.SetConfigFile(cfgFile)
+	} else {
+		// Find home directory.
+		home, err := homedir.Dir()
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+
+		// Search config in home directory with name ".asynqmon" (without extension).
+		viper.AddConfigPath(home)
+		viper.SetConfigName(".asynqmon")
+	}
+
+	viper.AutomaticEnv() // read in environment variables that match
+
+	// If a config file is found, read it in.
+	if err := viper.ReadInConfig(); err == nil {
+		fmt.Println("Using config file:", viper.ConfigFileUsed())
+	}
+}

tools/asynqmon/cmd/stats.go

@@ -0,0 +1,66 @@
+package cmd
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strings"
+	"text/tabwriter"
+
+	"github.com/go-redis/redis/v7"
+	"github.com/hibiken/asynq/internal/rdb"
+	"github.com/spf13/cobra"
+)
+
+// statsCmd represents the stats command
+var statsCmd = &cobra.Command{
+	Use:   "stats",
+	Short: "Shows current state of the queues",
+	Long: `Stats command shows the number of tasks in each queue at that instant.
+
+To monitor the queues continuously, it's recommended that you run this
+command in conjunction with the watch command.
+
+Example: watch -n 5 asynqmon stats`,
+	Run: func(cmd *cobra.Command, args []string) {
+		stats(cmd, args)
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(statsCmd)
+
+	// Here you will define your flags and configuration settings.
+
+	// Cobra supports Persistent Flags which will work for this command
+	// and all subcommands, e.g.:
+	// statsCmd.PersistentFlags().String("foo", "", "A help for foo")
+
+	// Cobra supports local flags which will only run when this command
+	// is called directly, e.g.:
+	// statsCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+}
+
+func stats(cmd *cobra.Command, args []string) {
+	c := redis.NewClient(&redis.Options{
+		Addr: "localhost:6379",
+		DB:   2,
+	})
+	r := rdb.NewRDB(c)
+
+	stats, err := r.CurrentStats()
+	if err != nil {
+		log.Fatal(err)
+	}
+	printStats(stats)
+	fmt.Println()
+}
+
+func printStats(s *rdb.Stats) {
+	format := strings.Repeat("%v\t", 5) + "\n"
+	tw := new(tabwriter.Writer).Init(os.Stdout, 0, 8, 2, ' ', 0)
+	fmt.Fprintf(tw, format, "Enqueued", "InProgress", "Scheduled", "Retry", "Dead")
+	fmt.Fprintf(tw, format, "--------", "----------", "---------", "-----", "----")
+	fmt.Fprintf(tw, format, s.Enqueued, s.InProgress, s.Scheduled, s.Retry, s.Dead)
+	tw.Flush()
+}

tools/asynqmon/main.go

@@ -1,38 +1,7 @@
 package main
 
-import (
-	"fmt"
-	"log"
-	"os"
-	"strings"
-	"text/tabwriter"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-)
-
-// Example usage: watch -n5 asynqmon
+import "github.com/hibiken/asynq/tools/asynqmon/cmd"
 
 func main() {
-	c := redis.NewClient(&redis.Options{
-		Addr: "localhost:6379",
-		DB:   2,
-	})
-	r := rdb.NewRDB(c)
-
-	stats, err := r.CurrentStats()
-	if err != nil {
-		log.Fatal(err)
-	}
-	printStats(stats)
-	fmt.Println()
-}
-
-func printStats(s *rdb.Stats) {
-	format := strings.Repeat("%v\t", 5) + "\n"
-	tw := new(tabwriter.Writer).Init(os.Stdout, 0, 8, 2, ' ', 0)
-	fmt.Fprintf(tw, format, "Enqueued", "InProgress", "Scheduled", "Retry", "Dead")
-	fmt.Fprintf(tw, format, "--------", "----------", "---------", "-----", "----")
-	fmt.Fprintf(tw, format, s.Enqueued, s.InProgress, s.Scheduled, s.Retry, s.Dead)
-	tw.Flush()
+	cmd.Execute()
 }