取得權杖以使用精靈應用程式呼叫 Web API

以下範例示範如何在設定 appsettings.json 檔案時定義 Web API 的範圍。 此範例取自 GitHub 上的 .NET 主控台精靈程式碼範例。

{
    "AzureAd": {
        // Same AzureAd section as before.
    },

    "MyWebApi": {
        "BaseUrl": "https://localhost:44372/",
        "RelativePath": "api/TodoList",
        "RequestAppToken": true,
        "Scopes": [ "[Enter here the scopes for your web API]" ]
    }
}

final static String GRAPH_DEFAULT_SCOPE = "https://graph.microsoft.com/.default";

const tokenRequest = {
    scopes: [process.env.GRAPH_ENDPOINT + '.default'], // e.g. 'https://graph.microsoft.com/.default'
};

在 MSAL Python 中，設定檔應類似下列程式碼片段：

{
    "scope": ["https://graph.microsoft.com/.default"],
}

ResourceId = "someAppIDURI";
var scopes = new [] {  ResourceId+"/.default"};

使用 Microsoft.Identity.Web，您就不需要取得權杖。 如從精靈應用程式呼叫 Web API 中所見，您可以使用較高層級的 API。 不過，如果您使用需要權杖的 SDK，下列程式碼片段會示範如何取得此權杖。

using Microsoft.Extensions.DependencyInjection;
using Microsoft.Identity.Abstractions;
using Microsoft.Identity.Web;

// In the Program.cs, acquire a token for your downstream API

var tokenAcquirerFactory = TokenAcquirerFactory.GetDefaultInstance();
ITokenAcquirer acquirer = tokenAcquirerFactory.GetTokenAcquirer();
AcquireTokenResult tokenResult = await acquirer.GetTokenForUserAsync(new[] { "https://graph.microsoft.com/.default" });
string accessToken = tokenResult.AccessToken;

此程式碼擷取自 MSAL JAVA 開發範例。

private static IAuthenticationResult acquireToken() throws Exception {

     // Load token cache from file and initialize token cache aspect. The token cache will have
     // dummy data, so the acquireTokenSilently call will fail.
     TokenCacheAspect tokenCacheAspect = new TokenCacheAspect("sample_cache.json");

     IClientCredential credential = ClientCredentialFactory.createFromSecret(CLIENT_SECRET);
     ConfidentialClientApplication cca =
             ConfidentialClientApplication
                     .builder(CLIENT_ID, credential)
                     .authority(AUTHORITY)
                     .setTokenCacheAccessAspect(tokenCacheAspect)
                     .build();

     IAuthenticationResult result;
     try {
         SilentParameters silentParameters =
                 SilentParameters
                         .builder(SCOPE)
                         .build();

         // try to acquire token silently. This call will fail since the token cache does not
         // have a token for the application you are requesting an access token for
         result = cca.acquireTokenSilently(silentParameters).join();
     } catch (Exception ex) {
         if (ex.getCause() instanceof MsalException) {

             ClientCredentialParameters parameters =
                     ClientCredentialParameters
                             .builder(SCOPE)
                             .build();

             // Try to acquire a token. If successful, you should see
             // the token information printed out to console
             result = cca.acquireToken(parameters).join();
         } else {
             // Handle other exceptions accordingly
             throw ex;
         }
     }
     return result;
 }

以下程式碼片段說明在 MSAL Node 保密用戶端應用程式中取得權杖的方式：

try {
    const authResponse = await cca.acquireTokenByClientCredential(tokenRequest);
    console.log(authResponse.accessToken) // display access token
} catch (error) {
    console.log(error);
}

# The pattern to acquire a token looks like this.
result = None

# First, the code looks up a token from the cache.
# Because we're looking for a token for the current app, not for a user,
# use None for the account parameter.
result = app.acquire_token_silent(config["scope"], account=None)

if not result:
    logging.info("No suitable token exists in cache. Let's get a new one from Azure AD.")
    result = app.acquire_token_for_client(scopes=config["scope"])

if "access_token" in result:
    # Call a protected API with the access token.
    print(result["token_type"])
else:
    print(result.get("error"))
    print(result.get("error_description"))
    print(result.get("correlation_id"))  # You might need this when reporting a bug.

using Microsoft.Identity.Client;

// With client credentials flows, the scope is always of the shape "resource/.default" because the
// application permissions need to be set statically (in the portal or by PowerShell), and then granted by
// a tenant administrator.
string[] scopes = new string[] { "https://graph.microsoft.com/.default" };

AuthenticationResult result = null;
try
{
 result = await app.AcquireTokenForClient(scopes)
                  .ExecuteAsync();
}
catch (MsalUiRequiredException ex)
{
    // The application doesn't have sufficient permissions.
    // - Did you declare enough app permissions during app creation?
    // - Did the tenant admin grant permissions to the application?
}
catch (MsalServiceException ex) when (ex.Message.Contains("AADSTS70011"))
{
    // Invalid scope. The scope has to be in the form "https://resourceurl/.default"
    // Mitigation: Change the scope to be as expected.
}

AcquireTokenForClient 使用應用程式權杖快取

在 MSAL.NET 中，AcquireTokenForClient 會使用應用程式權杖快取。 (所有其他 AcquireTokenXX 方法，都會運用使用者權杖快取。)請勿在呼叫 AcquireTokenSilent 之前呼叫 AcquireTokenForClient，因為 AcquireTokenSilent 會運用使用者權杖快取。 AcquireTokenForClient 會檢查應用程式權杖快取本身，並加以更新。

繼續本案例的下一篇文章：呼叫 Web API。

繼續本案例的下一篇文章：呼叫 Web API。

繼續本案例的下一篇文章：呼叫 Web API。

繼續本案例的下一篇文章：呼叫 Web API。

繼續本案例的下一篇文章：呼叫 Web API。