Add workers command to asynqmon

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- `asynqmon workers` was added to list all running workers information
+
 ## [0.4.0] - 2020-02-13
 
 ### Changed

internal/rdb/rdb.go

@@ -372,6 +372,7 @@ func (r *RDB) forwardSingle(src, dst string) error {
 var writeProcessInfoCmd = redis.NewScript(`
 redis.call("SETEX", KEYS[1], ARGV[2], ARGV[3])
 redis.call("ZADD", KEYS[2], ARGV[1], KEYS[1])
+redis.call("DEL", KEYS[3])
 for i = 4, table.getn(ARGV)-1, 2 do
 	redis.call("HSET", KEYS[3], ARGV[i], ARGV[i+1])
 end

tools/asynqmon/cmd/workers.go

@@ -0,0 +1,75 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"sort"
+
+	"github.com/go-redis/redis/v7"
+	"github.com/hibiken/asynq/internal/rdb"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+// workersCmd represents the workers command
+var workersCmd = &cobra.Command{
+	Use:   "workers",
+	Short: "Shows all running workers information",
+	Long: `Workers (asynqmon workers) will show all running workers information.
+
+The command shows the follwoing for each worker:
+* Process in which the worker is running
+* ID of the task worker is processing
+* Type of the task worker is processing
+* Payload of the task worker is processing
+* Queue that the task was pulled from.
+* Time the worker started processing the task`,
+	Args: cobra.NoArgs,
+	Run:  workers,
+}
+
+func init() {
+	rootCmd.AddCommand(workersCmd)
+}
+
+func workers(cmd *cobra.Command, args []string) {
+	r := rdb.NewRDB(redis.NewClient(&redis.Options{
+		Addr:     viper.GetString("uri"),
+		DB:       viper.GetInt("db"),
+		Password: viper.GetString("password"),
+	}))
+
+	workers, err := r.ListWorkers()
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	if len(workers) == 0 {
+		fmt.Println("No workers")
+		return
+	}
+
+	// sort by started timestamp or ID.
+	sort.Slice(workers, func(i, j int) bool {
+		x, y := workers[i], workers[j]
+		if x.Started != y.Started {
+			return x.Started.Before(y.Started)
+		}
+		return x.ID.String() < y.ID.String()
+	})
+
+	cols := []string{"Process", "ID", "Type", "Payload", "Queue", "Started"}
+	printRows := func(w io.Writer, tmpl string) {
+		for _, wk := range workers {
+			fmt.Fprintf(w, tmpl,
+				fmt.Sprintf("%s:%d", wk.Host, wk.PID), wk.ID, wk.Type, wk.Payload, wk.Queue, timeAgo(wk.Started))
+		}
+	}
+	printTable(cols, printRows)
+}