Sample Webapi to trigger TFS rest services & post HTTP calls - tfs

Question

I have been working on a requirement, i.e. when a bug is created/inprogress in TFS post a HTTP call to Slack (third party collaboration tool).
When a bug is closed post one more HTTP call to Slack.
I had implemented TFS server side plugin, unfortunately we don't have complete access to TFS and cannot implement. So, planning to implement Webapi and host it (say in Docker container) and whenever bug created / closed event happens in TFS it should post HTTP call.
I have created a simple console app with a method and it's working fine.
any sample code or thoughts to convert it to web api?
if I host, can it monitor TFS events and posts some HTTP calls?
public class GetWI
{
static void Main(string[] args)
{
GetWI ex = new GetWI();
ex.GetWorkItemsByWiql();
}
public void GetWorkItemsByWiql()
{
string _personalAccessToken = "xxxx";
string _credentials = Convert.ToBase64String(System.Text.ASCIIEncoding.ASCII.GetBytes(string.Format("{0}:{1}", "", _personalAccessToken)));
//this is needed because we want to create a project scoped query
string project = "Agileportfolio";
//create wiql object
var wiql = new
{
query = "Select [State], [Title] " +
"From WorkItems " +
"Where [Work Item Type] = 'Bug' " +
"And [System.TeamProject] = '" + project + "' " +
"And [System.State] = 'New' " +
"Order By [State] Asc, [Changed Date] Desc"
};
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("https://test.visualstudio.com");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", _credentials);
//serialize the wiql object into a json string
var postValue = new StringContent(JsonConvert.SerializeObject(wiql), Encoding.UTF8, "application/json"); //mediaType needs to be application/json for a post call
var method = new HttpMethod("POST");
var httpRequestMessage = new HttpRequestMessage(method, "https://abrahamdhanyaraj.visualstudio.com/_apis/wit/wiql?api-version=2.2") { Content = postValue };
var httpResponseMessage = client.SendAsync(httpRequestMessage).Result;
if (httpResponseMessage.IsSuccessStatusCode)
{
WorkItemQueryResult workItemQueryResult = httpResponseMessage.Content.ReadAsAsync<WorkItemQueryResult>().Result;
//now that we have a bunch of work items, build a list of id's so we can get details
var builder = new System.Text.StringBuilder();
foreach (var item in workItemQueryResult.WorkItems)
{
builder.Append(item.Id.ToString()).Append(",");
}
//clean up string of id's
string ids = builder.ToString().TrimEnd(new char[] { ',' });
HttpResponseMessage getWorkItemsHttpResponse = client.GetAsync("_apis/wit/workitems?ids=" + ids + "&fields=System.Id,System.Title,System.State&asOf=" + workItemQueryResult.AsOf + "&api-version=2.2").Result;
if (getWorkItemsHttpResponse.IsSuccessStatusCode)
{
var result = getWorkItemsHttpResponse.Content.ReadAsStringAsync().Result;
//Read title
}
}
// Create Channel
string name = "xyzz3";
var payload = new
{
token = "xoxp-291239704800-292962676087-297314229698-a80e720d98e443c8afb0c4cb2c09e745",
name = "xyzz3",
};
var serializedPayload = JsonConvert.SerializeObject(payload);
var response = client.PostAsync("https://slack.com/api/channels.create" + "?token=test&name=" + name + "&pretty=1",
new StringContent(serializedPayload, Encoding.UTF8, "application/json")).Result;
if (response.IsSuccessStatusCode)
{
dynamic content = JsonConvert.DeserializeObject(
response.Content.ReadAsStringAsync()
.Result);
}
}
}

Answer 1

I use wcf service to listen events from TFS. You may find my project here: https://github.com/ashamrai/tfevents
For wcf service:
Update your ServiceName.svc file and add:
Factory="System.ServiceModel.Activation.WebServiceHostFactory"
Create web method to use json:
[OperationContract]
[WebInvoke(Method = "POST", RequestFormat = WebMessageFormat.Json, BodyStyle = WebMessageBodyStyle.Bare)]
void WorkItemChangedEvent(Stream EventData);
Convert stream with Newtonsoft.Json to get information about event and work item:
StreamReader _reader = new StreamReader(pEventData, Encoding.UTF8);
string _eventStr = _reader.ReadToEnd();
WorkItemEventCore _wieventcorre = JsonConvert.DeserializeObject(_eventStr);
Then you have to create the subscription with url "http://host:port/service.svc/webmethod": https://learn.microsoft.com/en-us/vsts/service-hooks/services/webhooks

Answer 2

Instead of using a query and manually polling Visual Studio Team Services (VSTS), you can use a concept called WebHooks. You configure a WebHook in VSTS to listen for events and send these to a public endpoint. One event type is for Work Items. The endpoint can be any type of public endpoint, for example an Azure Function.
If the only thing you want to do is post the events to Slack, it's even easier because that's a standard integration point: Slack with VSTS.
This is much easier then using a server side plugin or writing your own Web API.