Dependent Request Extraction VSTS

Sometimes your extraction fails because what you are looking for is returned in a dependent request. Here is a plug-in you can use to scan dependent requests. You can adjust the below example to search the body or headers by changing “string body = e.Response .Headers.ToString();”. In the example the plugin is searching headers only.

        [Description("Extracts Text from the Response of a Dependent Request or any redirect using regex group")]

   public class FindTextInDependentRequestResponse : WebTestRequestPlugin
       Match match;
       public override void PostRequest(object sender, PostRequestEventArgs e)
           //Create a collection of all dependent requests
           WebTestRequestCollection dependents = e.Request.DependentRequests;
          //Gets the request that matches the filter URL and kicks off the postrequest event 
                             .Where (d => d.Url == URLFilter)
                             .Select (d => d)
                             .ForEach(d => {
                                 d.Cache = false;
                                 d.PostRequest += new EventHandler<PostRequestEventArgs>(this.PostDependentRequest);
       public void PostDependentRequest(object sender, PostRequestEventArgs e)
           if (e.ResponseExists)
               string body = e.Response.Headers.ToString();
               match = Regex.Match(body, RegexPattern, RegexOptions.Singleline);
               if (match != Match.Empty)
                   //Set value to equal the matched Regex
                   string value = match.Groups[1].Value;
                   //Add context param and set to value
                   e.WebTest.Context[TargetContextParam] = value;
                   //Add comment that the context param was created and a value was added
                   String.Format("Found Regex and created Param {0}",TargetContextParam)
                   String.Format("Could not find Regex to create Param {0}",TargetContextParam)
       [Description("The name of the context parameter to store the value")]
       public string TargetContextParam { get; set; }
       [Description("The Regex Pattern")]
       public string RegexPattern { get; set; }
       [Description("The url of the target dependent request")]
       public string URLFilter { get; set; }