Enable API to get current WebSocket connection number

* Background:

I want to kill gotty main process to release resources if not one use it, so required a method to get current WebSocket connections number

About use it definition:
* open in browser even without any input command. Or without any operation
* have any operations

Signed-off-by: Chenyang Yan <[email protected]>

Author: uddmorningsun

.gitignore

@@ -2,3 +2,4 @@ gotty
 builds
 js/dist
 js/node_modules/*
+.idea/*

server/handlers.go

@@ -8,6 +8,7 @@ import (
 	"log"
 	"net/http"
 	"net/url"
+	"strconv"
 	"sync/atomic"
 
 	"github.com/gorilla/websocket"
@@ -254,3 +255,10 @@ func (server *Server) titleVariables(order []string, varUnits map[string]map[str
 
 	return titleVars
 }
+
+func (server *Server) handleWSCount(c *counter) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json; chatset=utf-8")
+		w.Write([]byte(`{"number":` + strconv.Itoa(c.count()) + `}`))
+	}
+}

server/server.go

@@ -211,6 +211,8 @@ func (server *Server) setupHandlers(ctx context.Context, cancel context.CancelFu
 	siteMux.HandleFunc(pathPrefix+"auth_token.js", server.handleAuthToken)
 	siteMux.HandleFunc(pathPrefix+"config.js", server.handleConfig)
 
+	siteMux.HandleFunc(pathPrefix+"ws_count", server.handleWSCount(counter))
+
 	siteHandler := http.Handler(siteMux)
 
 	if server.options.EnableBasicAuth {