Azure 机器人服务的 Directline 没有响应并被 CORS 策略阻止

Question

我使用了 Microsoft Sample for Bot Services 中的 Bot Services sample。

我调试后，网页没有显示任何东西。这里有我的源代码：

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Web Chat: Minimal bundle with Markdown</title>
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />

    <script src="https://cdn.botframework.com/botframework-webchat/latest/webchat-minimal.js"></script>

    <style>
      html,
      body {
        height: 100%;
      }
      body {
        margin: 0;
      }
      #webchat {
        height: 100%;
        width: 100%;
      }
    </style>
</head>
<body>
<div id="webchat" role="main"></div>
    <script>
      (async function() {
         const res = await fetch('https://csharpbotdw.azurewebsites.net/directline/token', { method: 'POST' });
        const { token } = await res.json();
        const markdownIt = window.markdownit();
        window.WebChat.renderWebChat(
          {
                directLine: window.WebChat.createDirectLine({ token })

          },
          document.getElementById('webchat')
        );
        document.querySelector('#webchat > *').focus();
      })().catch(err => console.error(err));
    </script>
</body>
</html>

只看到错误提示

Access to fetch at 'https://csharpbotdw.azurewebsites.net/directline/token' from origin 'http://localhost:63191' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled. [http://localhost:63191/Test13122019]

Answer 1

您必须在应用程序服务的 CORS 菜单中的已批准来源列表中添加调用域运行您的 csharpbotdw 服务。

Answer 2

显然，您的 Azure 应用服务没有在托管代码的 Azure 应用服务的 CORS 设置中正确配置 CORS。我解决了，你试试看对你有没有帮助。

URL 似乎有问题：https://csharpbotdw.azurewebsites.net/directline/token 您获得了 directLine 令牌。每次我调用这个 URL 我都会得到一个 404 错误，似乎那里没有这样的 API。

如果您尚未在代码中实现此类 API，请在您的 .net Framework 项目中尝试以下代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using System.Web.Http;
using Newtonsoft.Json;

namespace CoreBot.Controllers
{
    [Route("api/token")]
    public class TokenController : ApiController
    {
        public async Task<IHttpActionResult> token()
        {
            var secret = "<your bot channel directline secret>";

            HttpClient client = new HttpClient();

            HttpRequestMessage request = new HttpRequestMessage(
                HttpMethod.Post,
                $"https://directline.botframework.com/v3/directline/tokens/generate");

            request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", secret);

            var userId = $"dl_{Guid.NewGuid()}";

            request.Content = new StringContent(
                Newtonsoft.Json.JsonConvert.SerializeObject(
                    new { User = new { Id = userId } }),
                    Encoding.UTF8,
                    "application/json");

            var response = await client.SendAsync(request);
            string token = String.Empty;

            if (response.IsSuccessStatusCode)
            {
                var body = await response.Content.ReadAsStringAsync();
                token = JsonConvert.DeserializeObject<DirectLineToken>(body).token;
            }

            var config = new ChatConfig()
            {
                token = token,
                userId = userId
            };

            return Ok(config);
        }

    }


    public class DirectLineToken
    {
        public string conversationId { get; set; }
        public string token { get; set; }
        public int expires_in { get; set; }
    }
    public class ChatConfig
    {
        public string token { get; set; }
        public string userId { get; set; }
    }
}

您可以在这里获取机器人频道直线秘密：

要将其集成到您的项目中，请在项目的控制器文件夹下创建一个 TokenController.cs 文件，并将上面的代码粘贴到其中：

并且在将项目发布到 Azure 后，您将能够通过 URL :https://csharpbotdw.azurewebsites.net/api/token by post 方法获取令牌。

本地测试结果：

启用 CORS 并将代码发布到 Azure 后，您可以使用 HTML 代码连接到您的机器人：

    <html xmlns="http://www.w3.org/1999/xhtml">
    <head runat="server">
    <title>Web Chat: Minimal bundle with Markdown</title>
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    
        <script src="https://cdn.botframework.com/botframework-webchat/latest/webchat-minimal.js"></script>
    
        <style>
          html,
          body {
            height: 100%;
          }
          body {
            margin: 0;
          }
          #webchat {
            height: 100%;
            width: 100%;
          }
        </style>
    </head>
    <body>
    <div id="webchat" role="main"></div>
        <script>
          (async function() {
             const res = await fetch('https://csharpbotdw.azurewebsites.net/api/token', { method: 'POST' });
            const { token } = await res.json();
            
            window.WebChat.renderWebChat(
              {
                    directLine: window.WebChat.createDirectLine({ token })
    
              },
              document.getElementById('webchat')
            );
            document.querySelector('#webchat > *').focus();
          })().catch(err => console.error(err));
        </script>
    </body>
    </html>

Azure 机器人服务的 Directline 没有响应并被 CORS 策略阻止

No response from Directline for Azure Bot Services and blocked by CORS policy

azure

cors

direct-line-botframework

azure-bot-service