Why does a request to a conversation thread reply fail with a C# HttpClient, but the same call suceeds with curl or Graph Explorer?

David Senk 0

I'm completely lost. I've resorted to just calling curl from C# as this is completely non-sensical to me. I started with using the Graph SDK, which I had multiple issues with, and I also received a "Not Found" error when trying to use graphClient.Groups[groupId].Threads[ThreadId].PostAsync(body) My current code looks like this:


var token =  await GetUserTokenAsync(); //gets the latest token from the GraphClient

using (var client = new HttpClient())
{
    client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
    using (var content = new StringContent(body))
    {
        content.Headers.ContentType = new MediaTypeHeaderValue("application/json");

        var postUrl = new UriBuilder($"https://graph.microsoft.com/v1.0/groups/{groupId}/threads/{threadId}/reply").ToString();

        var resp = await client.PostAsync(postUrl, content);

        if (!resp.IsSuccessStatusCode)
        {
            //same Url and body
            Console.WriteLine($"Error: Unable to post reply to group {groupId} thread {threadId}. The server said {await resp.Content.ReadAsStringAsync()}");
            String curlCommand = $"curl -i -X POST -H \"Authorization: Bearer {token}\" -H \"Content-Type: application/json\" -d '{body}' \"https://graph.microsoft.com/v1.0/groups/{groupId}/threads/{threadId}/reply\"";
            Console.WriteLine($"Try this with curl: {curlCommand}");
        }
    }
}

and when I run the generated curl command... it works? Exact same url, exact same token, exact same content type... but curl works, and HttpClient doesn't? What in the world am I missing?

Michael Taylor 56,861 Reputation points

2024-01-17T19:29:39.22+00:00
Please provide us the detailed response of the call. Within that information is the "why is it failing" part. The status code and actual response is critical.

Off the top of my head:

You are not correctly using HttpClient or DefaultRequestHeaders so if this is being called a lot or across threads then it will start failing. You create HttpClient once and reuse it for the life of the app. You should only set DefaultRequestHeaders when you are initializing the client. After that the headers must remain unchanged. To add per-request headers you have to create an HttpResponseMessage.

The url should be set as part of the HttpClient setup and just the resource information be passed as part of the request itself.

Note that what app is calling this and what version of the framework will impact how setup should occur. If you're using the Graph SDK then it provides wrapper types for credentials and clients so you shouldn't really be doing any of this. You only need the raw HttpClient, authentication and URL stuff if you're doing this manually. You can read more about how to use the SDK here.

David Senk 0

The HTTP Status code is 404, and the response message from Graph is:

{"error":{"code":"ErrorItemNotFound","message":"The specified object was not found in the store., Item not found."}}

I did this because the Graph SDK was not working. The Graph SDK was reporting NotFoundExceptions, and it said the HTTP Status Code was 400. I did this deliberately to try and see what the actual message was from the server (that is, seemingly, impossible to get out of the Graph SDK). The original code was more or less a simple call to graphClient.Groups[groupId].Threads[ThreadId].PostAsync(body)

public static async Task PostReplyToGroupThread(String groupId, String threadId, String reply)
{
    var body = new ReplyPostRequestBody()
    {
        Post = new Post
        {
            Body = new ItemBody
            {
                ContentType = BodyType.Text,
                Content = reply
            }
        }
    };

    await _userClient.Groups[groupId].Threads[threadId].Reply.PostAsync(body);
}

I understand that it is best practice to reuse the HttpClient, I tried to make the test case as "minimal" as possible. I did not want a possible issue to be with the HttpClient itself, so all of the setup for the HttpClient is right here. This will throw a 404 error on the very first call, so it is not "too many" HttpClient's being created. I have a breakpoint on this line of code:

var resp = await client.PostAsync(postUrl, content);

then step forward and read the response from the HttpClient. It will 404 from C#, then, using the "generated" curl command, I run that in another terminal... and it works. With all of that being said, I have done additional testing. With the following code, it works through the entire data set I currently have, and successfully posts all replies to the threads. It's ugly, but it seems that the issue is related to the timing between the creation of the conversation thread, and when replies are posted to it. Sometimes you can post replies right away. Other times, it takes up to 2 minutes before replies work. The data set I tested I had about ~10 requests (out of ~2000) make it to the "60 second" retry.

var token =  await GetUserTokenAsync();

using (var client = new HttpClient())
{
    client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
    using (var content = new StringContent(body, Encoding.UTF8, "application/json"))
    {
        var postUrl = $"https://graph.microsoft.com/v1.0/groups/{groupId}/threads/{threadId}/reply";

        var resp = await client.PostAsync(postUrl, content);

        if (resp.StatusCode == HttpStatusCode.NotFound)
        {
            Console.WriteLine("Info: Retrying post-reply (after 15 seconds), Graph returned 404...");
            await Task.Delay(TimeSpan.FromSeconds(15));
            resp = await client.PostAsync(postUrl, content);
        }

        if (resp.StatusCode == HttpStatusCode.NotFound)
        {
            Console.WriteLine("Info: Graph still says this doesn't exist. Waiting 45 more seconds and trying again...");
            await Task.Delay(TimeSpan.FromSeconds(45));
            resp = await client.PostAsync(postUrl, content);
        }

        if (resp.StatusCode == HttpStatusCode.NotFound)
        {
            Console.WriteLine("Info: Graph is really sure that this doesn't exist, but we'll try again in 60 seconds...");
            await Task.Delay(TimeSpan.FromSeconds(60));
            resp = await client.PostAsync(postUrl, content);
        }

        if (!resp.IsSuccessStatusCode)
        {
            //with my latest testing in a data set of ~2000 posts, this path never happened again.
            Console.WriteLine($"Error: Unable to post reply to group {groupId} thread {threadId}. The server said {await resp.Content.ReadAsStringAsync()}");
            String curlCommand = $"curl -i -X POST -H \"Authorization: Bearer {token}\" -H \"Content-Type: application/json\" -d '{body}' \"{postUrl}\"";
            Console.WriteLine($"Try this with curl: {curlCommand}");
        }

        Console.WriteLine("Posted!");
    }
}

Apparently, in my testing, I mostly got lucky, that the time between C# having a 404, and the time it took me to use curl/Graph Explorer to send the request, it would no longer 404. I could... possibly switch back to using the Graph SDK for this; however, the Graph SDK throws exceptions, and exceptions are expensive. I am most likely going to keep my manual request via HttpClient, but, I will use the shared HttpClient like I'm supposed to... Is there a documented time to wait in between creating a conversation thread and posting replies to it? Believe me, I would have much rather preferred not to do all of this manual effort. It would be great if the Graph SDK wasn't so "opaque" in the errors returned. A "status code" of 400, and a Microsoft.Kiota.OdataException, with no way to see what the server actually said, and what the request body actually was, is completely useless.

Michael Taylor 56,861 Reputation points

2024-01-17T22:21:44.51+00:00

I don't know that there is a delay in creating a conversation. The documented API returns 201 with the conversation object and its ID. That would seem to indicate it is created before the call returns. As such you should be able to use the returned data to immediately make additional calls. You might need to get the Azure team support to identify what is going wrong and why it might be delayed. Alternatively, if the blip is small, then you could simply retry until it succeeds after a create. But that depends on the context in which you're creating and trying to add to the conversation.

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Why does a request to a conversation thread reply fail with a C# HttpClient, but the same call suceeds with curl or Graph Explorer?

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