Realize the function that the same account can push each other when logging in on different devices

Statement one

If you want to implement the function of the same account logging in on different devices, you can refer to the following steps to set it up:

1. Store user login status : After the user logs in successfully, send a request to the server to store the user login status. You can use token or session to achieve this function.

2. Device Identification : Assign a unique identifier (such as a UUID) to each device so you can identify which device is logged into the account.

3. Check login status : When a user logs in on a device, the server needs to check the login status of the account. If the account has already logged in to other devices, the server needs to set the login status of other devices to invalid.

4. Notify the removed device : the server can send a notification to the removed device, informing the device that the user account has been logged in on other devices. After receiving the notification, the removed device needs to perform a logout operation, so that the user cannot continue to use the account on the device.

5. Update login status : When a user logs out of an account on a device, the server needs to set the login status of the device to invalid.

In this way, you have realized the function that the same account can push each other when logging in on different devices. Please note that this feature requires you to do corresponding processing on the server side.

Statement two

In order to realize the function that the same account can push each other when logging in on different devices, the following methods can be used:

1. Record the user's login status: record the user's login status on the server side, for example, use a cache or database table to save the user's login information, including user ID, login time, login IP and other information.

2. Check login status: When a user is logged in on another device, first check whether the user is already logged in on another device. If you have already logged in, you can mark the previous login status as invalid and prompt the user to log in on other devices.

3. Implement a login timeout mechanism: In order to prevent the user from directly closing the browser or application and causing the login status to remain, a login timeout mechanism can be implemented, such as setting a fixed time (such as 30 minutes) to indicate the user's login validity period. If the user logs in again within the validity period, update the user's login status and update the validity period time.

4. Realize the logout function: In order to facilitate the user to switch between different devices, a logout function can be implemented, allowing the user to actively choose to log out from the current device. When the user chooses to log out, the corresponding login status will be marked as invalid, and the user needs to log in again to access the account.

It should be noted that this implementation method may cause some user experience problems. For example, if the user forgets to log out after logging in on one device, and then logs in on another device, the previous login status will be invalidated, thereby affecting the user's operations. Therefore, it is necessary to weigh the pros and cons of the implementation and find a balance between user experience and security.

Statement three

This function can be achieved through the following steps:

1. Maintain a login device list and save all device information logged in by each account, such as device number, login time, etc.

2. For each login request, check whether the account is logged in on other devices. If so, you need to judge whether it needs to be topped off. It can be set according to business rules. For example, if there is no operation for more than N minutes, it can be blocked, or if the number of devices exceeds M, the earliest logged-in device will be blocked.

3. If other devices need to be removed, push a logout notification to other devices and remove these devices from the list of logged-in devices.

4. The current login device is added to the login device list, and information such as login time is stored.

5. Periodically clean up the login device list and remove devices that have not been logged in for a long time.

The specific implementation can be:

1. The login device list can be stored using a hash table, the key is the account ID, and the value is the device list.

2. When logging in, compare the current time with the login time of other devices in the list to determine whether the top-down condition is met. If so, call the interface to notify other devices to log out and remove it from the list.

3. Add the current device to the list, including device number, login timestamp and other information.

4. The background timer periodically scans the list to remove devices that have not logged in for more than the specified number of days.

5. In order to push the logout notification, each device needs to provide information such as the device number or Channel required for push when logging in. After the background login is successful, it will be recorded and used for subsequent pushes.

This solution requires the management and maintenance of a unified login device list in the background, and requires the device to have a push channel to facilitate the implementation of logout notifications in the background. The specific business will customize the TOP times or time rules according to the needs.