{"id":5911,"date":"2015-09-06T07:44:02","date_gmt":"2015-09-06T07:44:02","guid":{"rendered":"https:\/\/blogs.msdn.microsoft.com\/webdev\/2015\/09\/06\/integrating-with-slack-using-asp-net-webhooks-preview\/"},"modified":"2023-09-19T11:25:42","modified_gmt":"2023-09-19T18:25:42","slug":"integrating-with-slack-using-asp-net-webhooks-preview","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/dotnet\/integrating-with-slack-using-asp-net-webhooks-preview\/","title":{"rendered":"Integrating with Slack Using ASP.NET WebHooks Preview"},"content":{"rendered":"

In the blog Introducing Microsoft ASP.NET WebHooks Preview<\/a>, we gave an overview of how to work with Microsoft ASP.NET WebHooks. Slack<\/a> provides an interesting model where you can set up a WebHook to be fired when a certain trigger word is used in one of their messaging channels. In addition, it is possible for the WebHook to send data back<\/em> to the channel which is very useful. For example, if you have a trigger word AskMe:<\/strong> then you can get the WebHook to respond like this:<\/p>\n

\"SlackChannelMini\"<\/a><\/p>\n

WebHook Configuration<\/h3>\n

To setup Slack WebHooks<\/a> you need a Slack account. Then you configure the WebHook using what they call an Integration<\/strong> as follows:<\/p>\n

\"SlackIntegrations\"<\/a><\/p>\n

Pick the Outgoing WebHooks integration, <\/strong>select Add Outgoing WebHooks Integration<\/strong> and look for the fields Trigger Words<\/strong>, URLs<\/strong>, and Token<\/strong>. Fill in whatever trigger words and WebHook URI, and copy the Token<\/strong> for use later. The URI must have the form https:\/\/<host>\/api\/webhooks\/incoming\/slack<\/strong><\/b><\/p>\n

\"SlackWebHookConfiguration\"<\/a><\/p>\n

Configuring Receiver<\/h3>\n

The last part is to configure the WebHook receiver. After having installed the Microsoft.AspNet.WebHooks.Receivers.Slack<\/a><\/b> Nuget package into your ASP.NET application, this happens exactly like show in the blog Introducing Microsoft ASP.NET WebHooks Preview<\/a>:<\/p>\n

The first part of the configuration is done in WebApiConfig.cs<\/strong> where you add line 17 like this:<\/p>\n

\n
\n
   1:<\/span> public<\/span> static<\/span> class<\/span> WebApiConfig<\/pre>\n
<\/p>\n
   2:<\/span> {<\/pre>\n
<\/p>\n
   3:<\/span>     public<\/span> static<\/span> void<\/span> Register(HttpConfiguration config)<\/pre>\n
<\/p>\n
   4:<\/span>     {<\/pre>\n
<\/p>\n
   5:<\/span>         \/\/ Web API configuration and services<\/span><\/pre>\n
<\/p>\n
   6:<\/span>  <\/pre>\n
<\/p>\n
   7:<\/span>         \/\/ Web API routes<\/span><\/pre>\n
<\/p>\n
   8:<\/span>         config.MapHttpAttributeRoutes();<\/pre>\n
<\/p>\n
   9:<\/span>  <\/pre>\n
<\/p>\n
  10:<\/span>         config.Routes.MapHttpRoute(<\/pre>\n
<\/p>\n
  11:<\/span>             name: "DefaultApi"<\/span>,<\/pre>\n
<\/p>\n
  12:<\/span>             routeTemplate: "api\/{controller}\/{id}"<\/span>,<\/pre>\n
<\/p>\n
  13:<\/span>             defaults: new<\/span> { id = RouteParameter.Optional }<\/pre>\n
<\/p>\n
  14:<\/span>         );<\/pre>\n
<\/p>\n
  15:<\/span>  <\/pre>\n
<\/p>\n
  16:<\/span>         \/\/ Load Slack receiver<\/span><\/pre>\n
<\/p>\n
  17:<\/span>         config.InitializeReceiveSlackWebHooks();<\/pre>\n
<\/p>\n
  18:<\/span>     }<\/pre>\n
<\/p>\n
  19:<\/span> }<\/pre>\n
<\/div>\n<\/div>\n
The second part is to set the secret token so that it can be verified by the receiver. This is done by setting the MS_WebHookReceiverSecret_Slack<\/strong> app setting for your Web Application to the value of the secret Token obtained from before. As stated in the blog Introducing Microsoft ASP.NET WebHooks Preview<\/a>, the preferred way to do this is to set it in the Azure Portal:<\/p>\n
\"AzureAppSettings\"<\/a><\/p>\n
Defining a Handler<\/h3>\n
Slack sends WebHook data in the form of HTML Form data so we read it as a NameValueCollection<\/strong>. Further, as the Slack WebHook can return data, we use the Response<\/strong> property on the WebHookHandlerContext<\/strong> to define the data we want to return. The SlackResponse<\/strong> is just a helper formatting the response as expected by Slack.<\/p>\n
\n
\n
   1:<\/span> public<\/span> class<\/span> SlackWebHookHandler : WebHookHandler<\/pre>\n
<\/p>\n
   2:<\/span> {<\/pre>\n
<\/p>\n
   3:<\/span>     public<\/span> override<\/span> Task ExecuteAsync(string<\/span> generator, WebHookHandlerContext context)<\/pre>\n
<\/p>\n
   4:<\/span>     {<\/pre>\n
<\/p>\n
   5:<\/span>         NameValueCollection nvc;<\/pre>\n
<\/p>\n
   6:<\/span>         if<\/span> (context.TryGetData<NameValueCollection>(out<\/span> nvc))<\/pre>\n
<\/p>\n
   7:<\/span>         {<\/pre>\n
<\/p>\n
   8:<\/span>             string<\/span> question = nvc["subtext"<\/span>];<\/pre>\n
<\/p>\n
   9:<\/span>             string<\/span> msg = string<\/span>.Format("The answer to '{0}' is '{1}'."<\/span>, question, "Often"<\/span>);<\/pre>\n
<\/p>\n
  10:<\/span>             SlackResponse reply = new<\/span> SlackResponse(msg);<\/pre>\n
<\/p>\n
  11:<\/span>             context.Response = context.Request.CreateResponse(reply);<\/pre>\n
<\/p>\n
  12:<\/span>         }<\/pre>\n
<\/p>\n
  13:<\/span>         return<\/span> Task.FromResult(true<\/span>);<\/pre>\n
<\/p>\n
  14:<\/span>     }<\/pre>\n
<\/p>\n
  15:<\/span> }<\/pre>\n
<\/div>\n<\/div>\n
Trying it Out<\/h3>\n
Once deployed, we are ready to try this out: In a Slack channel write something like this AskMe: You there?<\/strong> You should now be called in your handler and see a response on the Slack channel like this:<\/p>\n
\"SlackChannel\"<\/a><\/p>\n
This should hopefully be enough to get you started receiving WebHooks from Slack using ASP.NET WebHooks Preview.<\/p>\n
Have fun!<\/p>\n
Henrik<\/p>\n","protected":false},"excerpt":{"rendered":"
In the blog Introducing Microsoft ASP.NET WebHooks Preview, we gave an overview of how to work with Microsoft ASP.NET WebHooks. Slack provides an interesting model where you can set up a WebHook to be fired when a certain trigger word is used in one of their messaging channels. In addition, it is possible for the […]<\/p>\n","protected":false},"author":403,"featured_media":58792,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[197],"tags":[34,7505,7506],"class_list":["post-5911","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-aspnet","tag-asp-net-web-api","tag-asp-net-webhooks","tag-webhooks"],"acf":[],"blog_post_summary":"
In the blog Introducing Microsoft ASP.NET WebHooks Preview, we gave an overview of how to work with Microsoft ASP.NET WebHooks. Slack provides an interesting model where you can set up a WebHook to be fired when a certain trigger word is used in one of their messaging channels. In addition, it is possible for the […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/posts\/5911","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/users\/403"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/comments?post=5911"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/posts\/5911\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/media\/58792"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/media?parent=5911"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/categories?post=5911"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/dotnet\/wp-json\/wp\/v2\/tags?post=5911"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}