A TDS Post Deploy Step for sending Slack notifications

SendSlackMessagePostDeployAction.cs

using HedgehogDevelopment.SitecoreProject.PackageInstallPostProcessor.Contracts;
using System;
using System.Collections.Specialized;
using System.ComponentModel;
using System.IO;
using System.Net;
using System.Web;
using System.Xml.Linq;

namespace MyProject.PostDeployActions
{
  [Serializable]
  [Description("Sends a Slack notification message after a successful deployment.\nSpecify a 'webhookUrl' and 'payload' parameter in query string notation below.")]
  public class SendSlackMessagePostDeployAction : IPostDeployAction
  {
    public void RunPostDeployAction(XDocument deployedItems, IPostDeployActionHost host, string parameter)
    {
      NameValueCollection parameters = HttpUtility.ParseQueryString(parameter ?? string.Empty);

      Uri webhookUrl;
      if (!Uri.TryCreate(parameters["webhookUrl"], UriKind.Absolute, out webhookUrl))
      {
        host.LogMessage("[SendSlackMessagePostDeployAction] 'webHookUrl' parameter is required.");
        return;
      }

      string payload = parameters["payload"];
      if (string.IsNullOrWhiteSpace(payload))
      {
        host.LogMessage("[SendSlackMessagePostDeployAction] 'payload' parameter is required.");
        return;
      }

      InvokeWebhookForUrl(webhookUrl, payload);

      host.LogMessage("[SendSlackMessagePostDeployAction] Post deploy action completed successfully.");
    }

    private static void InvokeWebhookForUrl(Uri webhookUrl, string payload)
    {
      var request = (HttpWebRequest)WebRequest.Create(webhookUrl);

      request.ContentType = "application/json";
      request.Method = "POST";

      using (var streamWriter = new StreamWriter(request.GetRequestStream()))
      {
        streamWriter.Write(payload);
      }

      var response = (HttpWebResponse)request.GetResponse();
      var stream = response.GetResponseStream();
      if (stream != null)
      {
        using (var streamReader = new StreamReader(stream))
        {
          streamReader.ReadToEnd();
        }
      }
    }
  }
}