在 C# 中使用 httpClient 时出现未经授权的 401 错误

Question

我正在使用 httpClient 调用受 Azure AAD 保护的 WebApi。 我调用 MSAL 库来获取令牌并设置标头，如下所示。

        private async void SetHeaders(HttpClient HttpClientObj)
        {
            IConfidentialClientApplication app;
            app = ConfidentialClientApplicationBuilder.Create(_configurationSettings.TestAppClientId)
                                    .WithClientSecret(_configurationSettings.TestAppClientSecret)
                                    .WithAuthority(new Uri(_configurationSettings.TestAppInstance + _configurationSettings.TestAppTenantId))
                                    .Build();

            AuthenticationResult result = null;

            IEnumerable<string> scopes = new List<string>() { _configurationSettings.TestAppAuthScope };
            try
            {
                result = await app.AcquireTokenForClient(scopes)
                                  .ExecuteAsync();
            }
            catch (MsalServiceException ex)
            {
                _logger.LogError("Exception Message: {ex}");
            }

            var defaultRequestHeaders = HttpClientObj.DefaultRequestHeaders;
            defaultRequestHeaders.Clear();

            if (defaultRequestHeaders.Accept == null || !defaultRequestHeaders.Accept.Any(m => m.MediaType == "application/json"))
            {
                HttpClientObj.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
            }

            try
            {
                defaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", result.AccessToken);
            }
            catch (Exception ex)
            {
                _logger.LogError("Exception Message: {ex}");
            }
        }

        private async Task<HttpResponseMessage> CallTestAppAPIToGetDataAsync(string testAppUri)
        {
                HttpResponseMessage response = null;

                HttpClient testHttpClientObj = new HttpClient();
                SetHeaders(testHttpClientObj);

                response = await testHttpClientObj.GetAsync(requestUri: gridstateUri);

                return response;
        }

我在 httpClientObj 调用 API 的行中添加了一个断点，我可以看到具有正确值的授权令牌。 当我尝试在邮递员中使用相同的标记访问相同的 uri 时，它工作正常，但在这里它给出了 401 Unauthorized。

                response = await testHttpClientObj.GetAsync(requestUri: gridstateUri);

Answer 1

您已将

SetHeaders

方法声明为

async

并使用 await

inside

，因此请尝试通过将声明更改为

async Task

来修复您的代码

private async Task SetHeaders(HttpClient HttpClientObj)
{
    ...
}

然后通过

await SetHeaders(testHttpClientObj)

等待此方法的结果，否则程序将继续而不等待任务完成