等到每个循环结束？

Question

在forEach循环后直接添加回调不起作用.我是node.js的新手,所以任何帮助都会受到赞赏,谢谢.

这是一个Minecraft机器人,记录玩家登录和注销时间.在我从服务器被踢之后我想在尝试重新加入之前结束所有玩家会话但是在下面的代码中即使我使用async.series它仍然不等到第一个功能完成 - 这是由于我的回调的位置？

bot.on('kicked', function(reason) {
  console.log("I got kicked for", reason, "lol");
  var timestamp = getTimestamp();

    async.series([
      function(callback) {
        console.log("logging out all players");
        logoutAllPlayers(timestamp, function(finished) {
          console.log("logged out all players " + finished);
          if (finished) {
            callback();
          }
        });
      },
      function(callback) { //don't execute until previous function has run completely
        //rejoin here
        bot = mineflayer.createBot(options);
        bindlisteners(bot);
      }
    ]);
});

...

回调的正确位置在哪里？

function logoutAllPlayers(timestamp, callback) {
      findOnlinePlayers(function(onlinePlayers) {
          if (onlinePlayers.length > 0) {
              onlinePlayers.forEach(function(player) {
                var playerId = player.id;
                var username = player.username;

                async.waterfall([
                  function(callback) { //add logout event
                    addEvent(playerId, 2, timestamp, function(logoutEventId) {
                      console.log("[" + timestamp + "] " + "Created logout: " + logoutEventId + " for " + username + " (" + playerId +")");
                      callback(null, logoutEventId);
                    });
                  },
                  function(logoutEventId, callback) { //find players current session
                    findSession(playerId, function(sessionId, loginEventId) {
                      console.log("[" + timestamp + "] " + "Found session: " + sessionId +" for " + username + " (" + playerId +")");
                      callback(null, sessionId, loginEventId, logoutEventId); 
                    });
                  },
                  function(sessionId, loginEventId, logoutEventId, callback) { //get timestamps for login and logout events to find the duration of session
                    findEventTimestamp(loginEventId, function(loginTimestamp) {
                      findEventTimestamp(logoutEventId, function(logoutTimestamp) {
                        var difference = diffBetweenTimestamps(loginTimestamp, logoutTimestamp);
                        console.log("[" + timestamp + "] " + "Duration: " + difference + " for " + username);
                        callback(null, sessionId, logoutEventId, difference, callback);
                      }); 
                    });
                  },
                  function(sessionId, logoutEventId, difference, callback) { //end session and update online status
                    endSession(sessionId, logoutEventId, difference, function(callback) {
                      console.log("[" + timestamp + "] " + "Updated session: " + sessionId + " for " + username + " (" + playerId +")");
                      updatenOnlineStatus(playerId, false); 
                    });     
                  }
                ]);
            });
            callback(true);
          }
      });
    }

Answer 1

在logoutAllPlayers,你调用callback(true); 之前您的async.waterfall通话已完成它的步骤.

相反,你应该调用最终的瀑布callback从//end session and update online status,然后改变你的瀑布的最后一行有一个完成回调.

async.waterfall([
  // ...
], function(){
  callback(true);
});