Dashboard: Stop|Resume worker pools work at runtime

src/dashboard/dashboard.go

@@ -43,6 +43,10 @@ type PageData struct {
 	Stats worker.Statistics
 }
 
+type PoolStop struct {
+	Stop bool `json:"stop"`
+}
+
 func NewDashboard(port uint16, webConf *config.Conf, pool *worker.Pool) *Dashboard {
 	mux := http.NewServeMux()
 	res, err := fs.Sub(resFS, "res")
@@ -52,6 +56,7 @@ func NewDashboard(port uint16, webConf *config.Conf, pool *worker.Pool) *Dashboa
 	}
 
 	mux.Handle("/static/", http.FileServer(http.FS(res)))
+
 	mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
 		template, err := template.ParseFS(res, "*.html")
 		if err != nil {
@@ -62,6 +67,35 @@ func NewDashboard(port uint16, webConf *config.Conf, pool *worker.Pool) *Dashboa
 		template.ExecuteTemplate(w, "index.html", nil)
 	})
 
+	mux.HandleFunc("/stop", func(w http.ResponseWriter, req *http.Request) {
+		var stop PoolStop
+
+		requestBody, err := io.ReadAll(req.Body)
+		if err != nil {
+			http.Error(w, "Failed to read request body", http.StatusInternalServerError)
+			logger.Error("Failed to read stop|resume signal from dashboard request: %s", err)
+			return
+		}
+		defer req.Body.Close()
+
+		err = json.Unmarshal(requestBody, &stop)
+		if err != nil {
+			http.Error(w, "Failed to unmarshal stop|resume signal", http.StatusInternalServerError)
+			logger.Error("Failed to unmarshal stop|resume signal from dashboard UI: %s", err)
+			return
+		}
+
+		if stop.Stop {
+			// stop worker pool
+			pool.Stop()
+			logger.Info("Stopped worker pool via request from dashboard")
+		} else {
+			// resume work
+			pool.Work()
+			logger.Info("Resumed work via request from dashboard")
+		}
+	})
+
 	mux.HandleFunc("/stats", func(w http.ResponseWriter, req *http.Request) {
 		jsonStats, err := json.MarshalIndent(pool.Stats, "", " ")
 		if err != nil {

src/dashboard/res/index.html

@@ -68,6 +68,9 @@ <h2>Statistics</h2>
                     </li>
                 </ol>
             </div>
+
+            <button class="btn btn-primary" id="btn_stop">Stop</button>
+            <button class="btn btn-primary" id="btn_resume" disabled>Resume</button>
         </div>
 
         <div style="height: 3rem;"></div>
@@ -117,6 +120,44 @@ <h2>Configuration</h2>
         let applyConfButton = document.getElementById("config_apply_button");
         let confQuery = document.getElementById("conf_query");
         let confIsRegexp = document.getElementById("conf_is_regexp");
+        let buttonStop = document.getElementById("btn_stop");
+        let buttonResume = document.getElementById("btn_resume");
+
+        buttonStop.addEventListener("click", (event) => {
+            buttonStop.disabled = true;
+            buttonResume.disabled = false;
+
+            // stop worker pool
+            let signal = {
+                "stop": true,
+            };
+
+            fetch("/stop", {
+                method: "POST",
+                headers: {
+                    "Content-type": "application/json",
+                },
+                body: JSON.stringify(signal),
+            });
+        });
+
+        buttonResume.addEventListener("click", (event) => {
+            buttonResume.disabled = true;
+            buttonStop.disabled = false;
+
+            // resume worker pool's work
+            let signal = {
+                "stop": false,
+            };
+
+            fetch("/stop", {
+                method: "POST",
+                headers: {
+                    "Content-type": "application/json",
+                },
+                body: JSON.stringify(signal),
+            });
+        });
 
         applyConfButton.addEventListener("click", (event) => {
             let query = String(confQuery.value);
@@ -139,8 +180,6 @@ <h2>Configuration</h2>
                 },
             };
 
-            console.log(newConf);
-
             fetch("/conf", {
                 method: "POST",
                 headers: {

src/main.go

@@ -39,7 +39,7 @@ import (
 	"unbewohnte/wecr/worker"
 )
 
-const version = "v0.3.3"
+const version = "v0.3.4"
 
 const (
 	configFilename               string = "conf.json"