Before you make the config, please upgrade your NexT version to v6.0.6 or greater.

Please note the difference between site config file and theme config file

Go to Leancloud website leancloud.cn and sign up to Leancloud. Then login.
Click 1 to enter the console:
Then click 1 to create an app:
Type your app name in 1 in the pop up window(eg. "test"), then choose 2, which means developer's plan, and then click 3 to create the app:

Create Counter class and enable plugin in NexT

Click 1(app name) to enter the app manage page:
then click 1 to create a class for counter:
Type Counter in the pop up window in 1, check 2, then click 3:
Click 1 to enter the app setting, then click 2:

Paste App ID and App Key to theme config file_config.yml like this:

yml

leancloud_visitors:
  enable: true
  app_id: <<your app id>>
  app_key: <<your app key>>
  # Dependencies: https://github.com/theme-next/hexo-leancloud-counter-security
  security: true
  betterPerformance: false

Set domain whitelist: Click1, then type your domain into 2(protocol, domain and port should be exactly the same):

Deploy web engine to avoid your data being changed illegally

Click 1 -> 2 -> 3 by order
Click1:

In the pop up window, click 1 to choose type Hook, then choosebeforeUpdate in 2, choose Counter in 3. Paste code below into 4, then click 5 to save it:

javascript

var query = new AV.Query("Counter");
if (request.object.updatedKeys.indexOf('time') !== -1) {
    return query.get(request.object.id).then(function (obj) {
        if (obj.get("time") > request.object.get("time")) {
            throw new AV.Cloud.Error('Invalid update!');
        }
        return request.object.save();
    });
}

Click 1 to deploy after the message in the red rect shows up:
Click 1 in the pop up：
Click 1 to close the pop up window after the message in the red rect shows up:

Set access control for your database

Open theme config file_config.yml, set leancloud_visitors: security to true:
yml
```
leancloud_visitors:
  enable: true
  app_id: <<your app id>>
  app_key: <<your app key>>
  # Dependencies: https://github.com/theme-next/hexo-leancloud-counter-security
  security: true
  betterPerformance: false
```
Explaination for betterPerformance: Because the Leancloud developer's plan has limits in requst thread amount and running time, counter number may be very slow to load in some times. If set betterPerformance to true, counter number will be displayed quickly by assuming the request is accepted normally.
Open cmd then switch to root path of site, type commands to install hexo-leancloud-counter-security plugin:
```
npm install hexo-leancloud-counter-security --save
```

Open site config file_config.yml, add those config:

yml

leancloud_counter_security:
  enable_sync: true
  app_id: <<your app id>>
  app_key: <<your app key>
  username:
  password:

Type command:

hexo lc-counter register <<username>> <<password>>

hexo lc-counter r <<username>> <<password>>

Change <<username>> and <<password>> to your own username and password (no need to be the same as leancloud account). They will be used in the hexo deploying.

Open site config file_config.yml, change <<username>> and <<password>>to those you set above:

yml

leancloud_counter_security:
  enable_sync: true
  app_id: <<your app id>>
  app_key: <<your app key>
  username: <<your username>> # will be asked while deploying if be left blank
  password: <<your password>> # recommend to leave it blank for security, will be asked while deploying if be left blank

Add the deployer in the deploy of site config file_config.yml:

yml

deploy:
  - type: git
    repo: // your repo
    ...
  - type: leancloud_counter_security_sync

Return to the Leancloud console. Click 1 -> 2, check if there is a record added in the _User (the img below is using username "admin" for example):
Click 1 -> 2 -> 3 by order:
<del>Click 1(add_fields), then choose 2:</del>Do as below "create" setting(choose the user you create):
click 1(create), then choose 2, type the username in 3, then click 4 -> 5:

Now your page should be similar to this img after finishing the step.
Click 1(delete), then choose 2:

Now the bug is fixed.

See detailed version here: https://leaferx.online/2018/03/16/lc-security-en/

Sign up to Leancloud and create an app

Sign up to Leancloud and create an app

Create Counter class and enable plugin in NexT

Deploy web engine to avoid your data being changed illegally

Set access control for your database