添加依赖项

在应用的 build.gradle 文件中，添加以下 Credential Manager 依赖项：

Kotlin

dependencies {
    implementation("androidx.credentials:credentials:1.7.0-alpha02")
    implementation("androidx.credentials:credentials-play-services-auth:1.7.0-alpha02")
}

Groovy

dependencies {
    implementation "androidx.credentials:credentials:1.7.0-alpha02"
    implementation "androidx.credentials:credentials-play-services-auth:1.7.0-alpha02"
}

初始化 Credential Manager

使用应用或 activity 上下文创建 CredentialManager 对象。

// Use your app or activity context to instantiate a client instance of
// CredentialManager.
private val credentialManager = CredentialManager.create(context)

构建数字凭证请求

如需请求经过验证的电子邮件地址，请构建包含 GetDigitalCredentialOption 的 GetCredentialRequest。此选项需要一个格式为 OpenID 可验证演示 (OpenID4VP) 请求的 requestJson 字符串。

OpenID4VP 请求 JSON 必须遵循特定结构。当前提供商支持具有外部 "digital": {"requests": [...]} 封装容器的 JSON 结构。

    val nonce = generateSecureRandomNonce()

    // This request follows the OpenID4VP spec
    val openId4vpRequest = """
{
  "requests": [
    {
      "protocol": "openid4vp-v1-unsigned",
      "data": {
        "response_type": "vp_token",
        "response_mode": "dc_api",
        "nonce": "$nonce",
        "dcql_query": {
          "credentials": [
            {
              "id": "user_info_query",
              "format": "dc+sd-jwt",
               "meta": { 
                  "vct_values": ["UserInfoCredential"] 
               },
              "claims": [ 
                {"path": ["email"]}, 
                {"path": ["name"]},  
                {"path": ["given_name"]},
                {"path": ["family_name"]},
                {"path": ["picture"]},
                {"path": ["hd"]},
                {"path": ["email_verified"]}
              ]
            }
          ]
        }
      }
    }
  ]
}
"""

    val getDigitalCredentialOption = GetDigitalCredentialOption(requestJson = openId4vpRequest)
    val request = GetCredentialRequest(listOf(getDigitalCredentialOption))

接下来，将 openId4vpRequest JSON 封装在 GetDigitalCredentialOption 中，创建 GetCredentialRequest，然后调用 getCredential()。

向用户显示请求

使用 Credential Manager 内置界面向用户显示请求。

try {
    // Requesting Digital Credential from user...
    val result = credentialManager.getCredential(activity, request)

    when (val credential = result.credential) {
        is DigitalCredential -> {
            val responseJsonString = credential.credentialJson

            // Successfully received digital credential response.

            // Next, parse this response and send it to your server.
            // ...
        }

        else -> {
            // handle Unexpected State() - Up to the developer
        }
    }
} catch (e: Exception) {
    // handle exceptions - Up to the developer
}

在客户端上解析响应

收到响应后，您可以在客户端上执行初步解析。 这对于立即更新界面非常有用，例如显示用户的姓名。

以下代码提取了原始的选择性披露 JWT (SD-JWT)，并使用辅助程序对其声明进行解码。

// 1. Parse the outer JSON wrapper to get the `vp_token`
val responseData = JSONObject(responseJsonString)
val vpToken = responseData.getJSONObject("vp_token")

// 2. Extract the raw SD-JWT string
val credentialId = vpToken.keys().next()
val rawSdJwt = vpToken.getJSONArray(credentialId).getString(0)

// 3. Use your parser to get the verified claims
// Server-side validation/parsing is highly recommended.

// Assumes a local parser like the one in our SdJwtParser.kt sample
val claims = SdJwtParser.parse(rawSdJwt)
Log.d("TAG", "Parsed Claims: ${claims.toString(2)}")

// 4. Create your VerifiedUserInfo object with REAL data
val userInfo = VerifiedUserInfo(
    email = claims.getString("email"),
    displayName = claims.optString("name", claims.getString("email"))
)

处理响应

Credential Manager API 将返回 DigitalCredential 响应。

以下示例展示了原始 responseJsonString 的外观，以及在解析内部 SD-JWT 后声明的外观，其中您还会获得其他元数据以及经过验证的电子邮件地址：

/*
// Example of the raw JSON response from credential.credentialJson:
{
  "vp_token": {
    // This key matches the 'id' you set in your dcql_query
    "user_info_query": [
      // The SD-JWT string (Issuer JWT ~ Disclosures ~ Key Binding JWT)
      "eyJhbGciOiJ...~WyI...IiwgImVtYWlsIiwgInVzZXJAZXhhbXBsZS5jb20iXQ~...~eyJhbGciOiJ..."
    ]
  }
}

// Example of the parsed and verified claims from the SD-JWT on your server:
{
  "cnf": {
    "jwk": {..}
  },
  "exp": 1775688222,
  "iat": 1775083422,
  "iss": "https://verifiablecredentials-pa.googleapis.com",
  "vct": "UserInfoCredential",
  "email": "jane.doe.246745@gmail.com",
  "email_verified": true,
  "given_name": "Jane",
  "family_name": "Doe",
  "name": "Jane Doe",
  "picture": "http://example.com/janedoe/me.jpg",
  "hd": ""
}
 */

账号创建的服务器端验证

为了进行验证，您的应用必须将完整的 responseJsonString 发送到您的服务器以进行加密验证，然后才能创建账号或让用户登录。

服务器上的验证必须实现以下目标：

  • 验证签发者：确保 iss（签发者）字段与 https://verifiablecredentials-pa.googleapis.com 一致。
  • 验证签名：使用 https://verifiablecredentials-pa.googleapis.com/.well-known/vc-public-jwks 提供的公钥 (JWK) 检查 SD-JWT 的签名。

为确保完全安全，请务必验证 nonce 以防范重放攻击。

try {
    // Send the raw credential response and the original nonce to your server.
    // Your server must validate the response. createAccountWithVerifiedCredentials
    // is a custom implementation per each RP for server side verification and account creation.
    val serverResponse = createAccountWithVerifiedCredentials(responseJsonString, nonce)

    // Server returns the new account info (e.g., email, name)
    val claims = JSONObject(serverResponse.json)

    val userInfo = VerifiedUserInfo(
        email = claims.getString("email"),
        displayName = claims.optString("name", claims.getString("email"))
    )

    // handle response - Up to the developer
} catch (e: Exception) {
    // handle exceptions - Up to the developer
}

在预配账号后，建议您立即为该账号创建通行密钥，虽然这是可选步骤，但我们强烈建议您执行。这样可以为用户提供一种安全的无密码登录方法。此流程与标准通行密钥注册流程完全相同。

为了让该流程在 WebView 上正常运行，开发者应实现 JavaScript 桥接 (JS Bridge) 以方便移交。此桥接器允许 WebView 向原生应用发出信号，然后原生应用可以对 Credential Manager API 执行实际调用。