oklahomer/go-sarah

package main

import (
    "encoding/json"
    "github.com/oklahomer/go-kasumi/logger"
    "github.com/oklahomer/go-sarah/v4"
    "net/http"
    "runtime"
)

// setStatusHandler sets an endpoint that returns current status of go-sarah, its belonging sarah.Bot implementations and sarah.Worker.
//
//    curl -s -XGET   "http://localhost:8080/status" | jq .
//    {
//    "worker": [
//      {
//        "report_time": "2018-06-23T15:22:37.274064679+09:00",
//        "queue_size": 0
//      },
//      {
//        "report_time": "2018-06-23T15:22:47.275251621+09:00",
//        "queue_size": 0
//      },
//      {
//        "report_time": "2018-06-23T15:22:57.272596709+09:00",
//        "queue_size": 0
//      },
//      {
//        "report_time": "2018-06-23T15:23:07.275004281+09:00",
//        "queue_size": 0
//      },
//      {
//        "report_time": "2018-06-23T15:23:17.276197523+09:00",
//        "queue_size": 0
//      }
//    ],
//      "runtime": {
//        "goroutine_count": 115,
//        "cpu_count": 4,
//        "gc_count": 1
//      },
//      "bot_system": {
//        "running": true,
//        "bots": [
//          {
//            "type": "nullBot",
//            "running": true
//          },
//          {
//            "type": "slack",
//            "running": true
//          }
//        ]
//      }
//    }
func setStatusHandler(mux *http.ServeMux, ws *workerStats) {
    mux.HandleFunc("/status", func(writer http.ResponseWriter, request *http.Request) {
        runnerStatus := sarah.CurrentStatus()
        systemStatus := &botSystemStatus{}
        systemStatus.Running = runnerStatus.Running
        for _, b := range runnerStatus.Bots {
            bs := &botStatus{
                BotType: b.Type,
                Running: b.Running,
            }
            systemStatus.Bots = append(systemStatus.Bots, bs)
        }

        var memStats runtime.MemStats
        runtime.ReadMemStats(&memStats)
        status := &status{
            Worker: ws.history(),
            Runtime: &runtimeStatus{
                NumGoroutine: runtime.NumGoroutine(),
                NumCPU:       runtime.NumCPU(),
                NumGC:        memStats.NumGC,
            },
            BotRunner: systemStatus,
        }
        bytes, err := json.Marshal(status)
        if err == nil {
            writer.Header().Set("Content-Type", "application/json")
            _, _ = writer.Write(bytes)
        } else {
            logger.Errorf("Failed to parse json: %+v", err)
            http.Error(writer, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
        }
    })
}

type status struct {
    Worker    []workerStatsElem `json:"worker"`
    Runtime   *runtimeStatus    `json:"runtime"`
    BotRunner *botSystemStatus  `json:"bot_system"`
}

type runtimeStatus struct {
    NumGoroutine int    `json:"goroutine_count"`
    NumCPU       int    `json:"cpu_count"`
    NumGC        uint32 `json:"gc_count"`
}

type botStatus struct {
    BotType sarah.BotType `json:"type"`
    Running bool          `json:"running"`
}

type botSystemStatus struct {
    Running bool         `json:"running"`
    Bots    []*botStatus `json:"bots"`
}