Add config for toobusy middleware

With very low CPU frequency or bad IO situation, as well as not-loaded
JS CodiMD happens to present unneeded "I'm busy"-messages to users.

This patch allows to configure the lag. The default is taken from the
libray but set in our own default configs.

Signed-off-by: Sheogorath <sheogorath@shivering-isles.com>

lib/config/default.js

@@ -56,6 +56,8 @@ module.exports = {
   // socket.io
   heartbeatInterval: 5000,
   heartbeatTimeout: 10000,
+  // too busy timeout
+  tooBusyLag: 70,
   // document
   documentMaxLength: 100000,
   // image upload setting, available options are imgur/s3/filesystem/azure/lutim

lib/config/environment.js

@@ -33,6 +33,7 @@ module.exports = {
   dbURL: process.env.CMD_DB_URL,
   sessionSecret: process.env.CMD_SESSION_SECRET,
   sessionLife: toIntegerConfig(process.env.CMD_SESSION_LIFE),
+  tooBusyLag: toIntegerConfig(process.env.CMD_TOOBUSY_LAG),
   imageUploadType: process.env.CMD_IMAGE_UPLOAD_TYPE,
   imgur: {
     clientID: process.env.CMD_IMGUR_CLIENTID

lib/web/middleware/tooBusy.js

@@ -2,7 +2,11 @@
 
 const toobusy = require('toobusy-js')
 
+
 const response = require('../../response')
+const config = require('../../config')
+
+toobusy.maxLag(config.tooBusyLag)
 
 module.exports = function (req, res, next) {
   if (toobusy()) {