Microsoft.Graph NuGet ItemAttachment contents

Question

Up until my last update of the Microsoft.Graph NuGet 5.2 package I was able to obtain the contents of message attachments of type ItemAttachment (i.e. emails attached to an email). It wasn't the most elegant method, but it worked.

        public async Task<string?> GetMessageAttachment(string upn, string msgId, string attId)
        {
            // create request url
            var requestUrl = graphClient.Users[upn].Messages[msgId].Attachments[attId].ToGetRequestInformationAppendSegmentToRequestUrl("$value");
            // create request
            var hrm = new HttpRequestMessage(HttpMethod.Get, requestUrl);
            // authenticate request
            await graphClient.AuthenticationProvider.AuthenticateRequestAsync(hrm);
            try
            {
                // send request and read response
                var response = await graphClient.HttpProvider.SendAsync(hrm);
                // read content
                var content = await response.Content.ReadAsStringAsync();
                return content;
            }
            catch (Exception ex)
            {
                throw;
            }
        }

The latest version of the SDK has removed the properties and methods that made this possible. FileAttachment types still work perfectly, but I can't obtain the raw contents of an ItemAttachment any longer. Does anyone have a solution for this? I've spent way too much time searching the internet and forums for the solution and none of them cover the latest SDK package.

Answer 1

You can modify the urlTemplate as another workaround eg the following for me works on 5.2

            var requestInformation = graphServiceClient.Me.Messages["AA..."].Attachments["AA..."].ToGetRequestInformation();
            requestInformation.UrlTemplate = requestInformation.UrlTemplate.Insert(requestInformation.UrlTemplate.Length, "/$value");           
            var attachmentStream = graphServiceClient.RequestAdapter.SendPrimitiveAsync<System.IO.Stream>(requestInformation).GetAwaiter().GetResult();
            using (var fileStream = File.Create("C:\\temp\\attachmentMessage.eml"))
            {
                attachmentStream.Seek(0, SeekOrigin.Begin);
                attachmentStream.CopyTo(fileStream);
            }
            Console.WriteLine("Done");