循环不适用于间隔

Question

我正在使用 Firebase 和 Twitter API 创建一个 Twitter 机器人来取消关注非活动帐户。

这是 Nodejs 代码：

// Get the screen_names in `to_unfollow` table
firebase.database().ref("to_unfollow/" + settings.PERSON_TWITTER_HANDLE).on("value", function(snapshot) {

// Functional Loop
var i = 0;
function timedLoop() { // unFollows the user after every `x` seconds

      /*=============================================>>>>>
      = Thing to be done =
      ===============================================>>>>>*/

        function snapshotToArray(snapshot) { // This function converts the Snapshot data into an array
            var returnArr = [];

            snapshot.forEach(function(childSnapshot) {
                var item = childSnapshot.val();
                item.key = childSnapshot.key;

                returnArr.push(item);
            });

            return returnArr;
        };

        var screen_name_to_unfollow = snapshotToArray(snapshot)[i].key;

        console.log(screen_name_to_unfollow);

      /*= End of Thing to be done =*/
      /*=============================================<<<<<*/

      // Increase value of variable `i` by 1. (Increment)
      i++;

      // How many times to loop
      if(i < 5000) {
          setTimeout( timedLoop, 1000*20 ); // timedLoop();
      }

  }

  timedLoop(); // Run the loop

});

在这里，我的循环运行良好。 screen_name_to_unfollow 变量每 20 秒登录一次控制台。

---

但是当我添加执行代码以取消关注人员时，循环工作......但不是有时间间隔。它只是不断取消关注人。

我的代码看起来是这样的：

// Get the screen_names in `to_unfollow` table
firebase.database().ref("to_unfollow/" + settings.PERSON_TWITTER_HANDLE).on("value", function(snapshot) {

// Functional Loop
var i = 0;
function timedLoop() { // unFollows the user after every `x` seconds

      /*=============================================>>>>>
      = Thing to be done =
      ===============================================>>>>>*/

        function snapshotToArray(snapshot) { // This function converts the Snapshot data into an array
            var returnArr = [];

            snapshot.forEach(function(childSnapshot) {
                var item = childSnapshot.val();
                item.key = childSnapshot.key;

                returnArr.push(item);
            });

            return returnArr;
        };

        var screen_name_to_unfollow = snapshotToArray(snapshot)[i].key;

        console.log(screen_name_to_unfollow);

        // UnFollow
        T.post('friendships/destroy', { screen_name: screen_name_to_unfollow },  function (err, data, response) {
          console.log('T.Post', new Date());
          if(!err){
            console.log(settings.PERSON_NICKNAME + " follower " + screen_name_to_unfollow + " unfollowed.");

            // Create an `unfollowed` table and insert the screen_name there
            firebase.database().ref("unfollowed").child(settings.PERSON_TWITTER_HANDLE).update({
              [screen_name_to_unfollow]: {
                connection: "unfollowed"
              }
            });

            // Delete the screen_name from `to_unfollow` table
            firebase.database().ref("to_unfollow/" + settings.PERSON_TWITTER_HANDLE).child(screen_name_to_unfollow).remove();

          } else{
            console.log(err);
          }
        });

      /*= End of Thing to be done =*/
      /*=============================================<<<<<*/

      // Increase value of variable `i` by 1. (Increment)
      i++;

      // How many times to loop
      if(i < 5000) {
          setTimeout( timedLoop, 1000*20 ); // timedLoop();
      }

  }

  timedLoop(); // Run the loop

});

在终端中，您可以看到间隔没有解决。

T.Post 2018-05-31T02:11:27.234Z
Wesbos follower AnnSaid unfollowed.
T.Post 2018-05-31T02:11:27.914Z
Wesbos follower AnnyShivang unfollowed.
T.Post 2018-05-31T02:11:28.865Z
Wesbos follower AntJanus unfollowed.
T.Post 2018-05-31T02:11:29.888Z
Wesbos follower AnthonyCatonPR unfollowed.
T.Post 2018-05-31T02:11:30.975Z
Wesbos follower AppleLaa unfollowed.
T.Post 2018-05-31T02:11:31.733Z
Wesbos follower AsyrafDuyshart unfollowed.

在这种情况下我该怎么做才能使循环像以前一样工作？我希望每 20 秒后取消关注少数不活动的 Twitter 帐户，因为我不想陷入速率限制.

提前致谢 :-)

Answer 1

问题是 firebase 的 .on 侦听器，每次 T.post 结束时都会被调用，因为您要从 to_unfollow/ 中删除。

因此，每次T.post 结束时，您都会创建一个额外的setTimeout 循环，如果您让该代码运行几分钟，您将向 twitter 执行数千个请求。

改用.once 可以解决您的问题。并且在取消关注快照中的所有用户之后，您应该请求另一个设置为 firebase。