Token Authentication

---

Overview

When a user initializes ZEGO MiniGameEngine SDK, the ZEGO server checks whether the user has the permissions to use the mini-game service based on the token in the user request. This process is called token-based authentication. Token-based authentication prevents risks caused by insufficient permissions or improper operations.

How it works

Before you initialize ZEGO MiniGameEngine SDK, your server needs to generate a token. The ZEGO server checks whether the user is a legitimate user based on the token in the user request.

The following figure shows how to perform token-based authentication during initialization.

1. A client applies for a token.
2. The developer server generates a token and returns the token to the client.
3. The client initializes ZEGO MiniGameEngine SDK with the token.
4. ZEGO MiniGameEngine SDK automatically sends the token to the ZEGO server for authentication.
5. The ZEGO server returns the authentication result to ZEGO MiniGameEngine SDK.
6. ZEGO MiniGameEngine SDK returns the authentication result to the client. If the client is not authorized, the initialization fails.

Prerequisites

Before you perform token-based authentication, make sure that ZEGO MiniGameEngine SDK is integrated with the project. For more information, see Integrate the SDK.

Procedure

The following section describes how to generate a token on your server, configure the token by using ZEGO MiniGameEngine SDK, and handle an expired token.

1. Generate a token

1.1 Obtain the values of the AppID and ServerSecret parameters

Log in to the ZEGO console and create a project. Obtain the values of the AppID and ServerSecret parameters that are required to connect to the mini-game service. Then, contact ZEGO business staff to activate the mini-game service.

1.2 Generate a token on your server

For ease of use, ZEGO provides the open source zego_server_assistant plug-in on GitHub and Gitee. The plug-in supports multiple programming languages, such as Go, C++, Java, Python, PHP, .NET, and Node.js. You can deploy the plug-in on your server to generate a token.

Take Go language as an example, you can do the following steps to generate a Token：

1. go get github.com/ZEGOCLOUD/zego_server_assistant
2. import "github.com/ZEGOCLOUD/zego_server_assistant/token/go/src/token04"
3. Call the GenerateToken04 method to generate a Token.

The following code shows how to generate a user identity Token:

package main

import (
    "fmt"
    "github.com/ZEGOCLOUD/zego_server_assistant/token/go/src/token04"
)

/*
Sample code for generating a user identity Token: 
*/

func main() {
    var appId uint32 = <Your AppId>   // The application ID that you obtain after you create a project in the ZEGO console. The value is of the UINT32 type.
    userId := <Your userID>  // The user ID that you specify. The value is of the STRING type.
    secret := <ServerSecret>  // The secret key that you obtain after you create a project in the ZEGO console. The value is a string of 32 bytes.
    var effectiveTimeInSeconds int64 = <Your token effectiveTime> // The validity period of the token. The value is of the INT64 type. Unit: seconds.
    var payload string = ""

    token, err := token04.GenerateToken04(appId, userId, serverSecret, effectiveTimeInSeconds, payload)
    if err != nil {
        fmt.Println(err)
        return
    }
    fmt.Println(token)
}

2. Configure the token

Pass in the token when you call the init operation to initialize ZEGO MiniGameEngine SDK.

// Initialize ZEGO Express SDK. Otherwise, you cannot receive the callback of the `init` operation.

// Initialize ZEGO MiniGameEngine SDK.
ZegoGameUserInfo *userInfo = [[ZegoGameUserInfo alloc] init];
// After you create a project in the [ZEGO console] (https://console.zego.im/), you can obtain the application ID from the project information. Append an "L" to the application ID. Example: 1234567890L.
long appID = 12345678L; 
NSString *token = @"your token"; // The token that your server generates.
userInfo.userID = @"your user ID"; // The custom user ID.
userInfo.userName = @"your user name"; // The custom username.
userInfo.avatar = @"your user avatar"; // The URL of the user avatar.
[ZegoMiniGameEngine.sharedEngine init:appID token:token userInfo:userInfo callBack:^(NSInteger errorCode2) {

}];

3. Update the token

The SDK sends a notification by using the onTokenWillExpire callback 30 seconds before the token expires.

After you receive the callback, you need to obtain a new token from your server and update the token by calling the updateToken operation provided by the SDK.

// Obtain a notification indicating that the token expires after 30 seconds.
- (void)onTokenWillExpire {
    // Updates the token.
    [ZegoMiniGameEngine.sharedEngine updateToken:@"The new token"];
}