Graph API to know when email is sent

Question

I am currently sending emails via Graph API using the following code:

var graphClient = GetAuthenticatedGraphClient();
var metadata = JsonSerializer.Deserialize<MyMetadata>(queueItem);

if (metadata is null) throw new InvalidOperationException("Could not convert metadata");
                
await graphClient.Users[metadata.MailboxUsername].Messages[metadata.OutlookPlugInIdentityGUID].Send().Request().PostAsync();

Whilst this works, I have no way of knowing when the email has actually sent. The code that I have considered to check is a while loop like this:

while (isSent == false)
{
    var checkMessage = await graphClient.Users[metadata.MailboxUsername].Messages[metadata.OutlookPlugInIdentityGUID].Request().GetAsync();

    if (checkMessage.IsDraft == false)
    {
        isSent = true;
    }
    else if (noOfAttempts > 50) { throw new Exception("some error message"); }
    
    noOfAttempts += 1;
    await Task.Delay(5000);
}

This is obviously very inefficient and runs the risk of causing Graph to throttle API calls which would potentially cause a performance bottleneck. Is there a cleaner and more efficient way of determining when an email has been successfully sent?

I need to know when the email has been sent so that I can trigger a separate process in sequence.

Thanks in advance!

Answer 1

You can send HTTP request and check the status code of the response.

Example:

var graphClient = GetAuthenticatedGraphClient();
var metadata = JsonSerializer.Deserialize<MyMetadata>(queueItem);

if (metadata is null) throw new InvalidOperationException("Could not convert metadata");
            
var requestUrl = graphClient.Users[metadata.MailboxUsername].Messages[metadata.OutlookPlugInIdentityGUID].Send().Request().RequestUrl;

// Create the request message and add the content.
var hrm = new HttpRequestMessage(HttpMethod.Post, requestUrl);

// Authenticate (add access token) our HttpRequestMessage
await graphClient.AuthenticationProvider.AuthenticateRequestAsync(hrm);

// Send the request and get the response.
var response = await graphClient.HttpProvider.SendAsync(hrm);

if (response.IsSuccessStatusCode)
{
    ...
}
else
    throw new ServiceException(
        new Error
        {
            Code = response.StatusCode.ToString(),
            Message = await response.Content.ReadAsStringAsync()
        });

Resources:

Send HTTP request