如何通过Webhooks在Azure Function中获取SharePoint列表附件

我们有一个包含大型PDF附件的SharePoint列表，已配置Azure Webhook以在列表发生变更时通知Azure Function App，希望能够检查并解析PDF附件。

我开发经验尚浅，已参考微软官方示例完成代码实现，测试中Azure Function已成功触发事件：

Monitor Invocation:

目前实现的代码基本与示例一致，主要功能为输出日志信息，但我找不到使用SharePoint列表获取附件的详细实现场景示例。

是否可以通过以下代码读取请求体获取附件数据？

var content = await new StreamReader(req.Body).ReadToEndAsync();

完整代码上下文：

#r "Newtonsoft.Json"
using System.Net;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using Newtonsoft.Json;

public static async Task<IActionResult> Run(HttpRequest req,
  ICollector<string> outputQueueItem, ILogger log)
{
  log.LogInformation($"Webhook was triggered!");

  // Grab the validationToken URL parameter
  string validationToken = req.Query["validationtoken"];

  // If a validation token is present, we need to respond within 5 seconds by
  // returning the given validation token. This only happens when a new
  // webhook is being added
  if (validationToken != null)
  {
    log.LogInformation($"Validation token {validationToken} received");
    return (ActionResult)new OkObjectResult(validationToken);
  }

  log.LogInformation($"SharePoint triggered our webhook...great :-)");
  //Is the attachment available via the content variable?
  var content = await new StreamReader(req.Body).ReadToEndAsync();
  log.LogInformation($"Received following payload: {content}");

  var notifications = JsonConvert.DeserializeObject<ResponseModel<NotificationModel>>(content).Value;
  log.LogInformation($"Found {notifications.Count} notifications");

  if (notifications.Count > 0)
  {
    log.LogInformation($"Processing notifications...");
    foreach(var notification in notifications)
    {
      // add message to the queue
      string message = JsonConvert.SerializeObject(notification);
      log.LogInformation($"Before adding a message to the queue. Message content: {message}");
      outputQueueItem.Add(message);
      log.LogInformation($"Message added :-)");
    }
  }

  // if we get here we assume the request was well received
  return (ActionResult)new OkObjectResult($"Added to queue");
}

// supporting classes
public class ResponseModel<T>
{
  [JsonProperty(PropertyName = "value")]
  public List<T> Value { get; set; }
}

public class NotificationModel
{
  [JsonProperty(PropertyName = "subscriptionId")]
  public string SubscriptionId { get; set; }

  [JsonProperty(PropertyName = "clientState")]
  public string ClientState { get; set; }

  [JsonProperty(PropertyName = "expirationDateTime")]
  public DateTime ExpirationDateTime { get; set; }

  [JsonProperty(PropertyName = "resource")]
  public string Resource { get; set; }

  [JsonProperty(PropertyName = "tenantId")]
  public string TenantId { get; set; }

  [JsonProperty(PropertyName = "siteUrl")]
  public string SiteUrl { get; set; }

  [JsonProperty(PropertyName = "webId")]
  public string WebId { get; set; }
}

public class SubscriptionModel
{
  [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
  public string Id { get; set; }

  [JsonProperty(PropertyName = "clientState", NullValueHandling = NullValueHandling.Ignore)]
  public string ClientState { get; set; }

  [JsonProperty(PropertyName = "expirationDateTime")]
  public DateTime ExpirationDateTime { get; set; }

  [JsonProperty(PropertyName = "notificationUrl")]
  public string NotificationUrl {get;set;}

  [JsonProperty(PropertyName = "resource", NullValueHandling = NullValueHandling.Ignore)]
  public string Resource { get; set; }
}

我尝试对Azure门户中运行的代码进行远程调试，以查看HttpRequest和StreamReader对象，但遇到诸多问题未能成功。

感谢您的帮助。

内容的提问来源于stack exchange，提问作者Tikhon