Скачать или смотреть The Correct Way to Implement Fire and Forget Async Method Calls

Discover how to efficiently implement fire and forget async method calls in ASP.NET Core, ensuring you never lose critical tasks such as sending emails.
---
This video is based on the question https://stackoverflow.com/q/64626369/ asked by the user 'Mohammad Akbari' ( https://stackoverflow.com/u/1890983/ ) and on the answer https://stackoverflow.com/a/64806282/ provided by the user 'Stephen Cleary' ( https://stackoverflow.com/u/263693/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Correct way to implement fire and forget async method call

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
The Correct Way to Implement Fire and Forget Async Method Calls

In the world of web development, asynchronous programming is key to creating responsive applications. However, when it comes to operations like sending emails, which primarily lean on queuing systems, many developers grapple with how to implement this from an async perspective, especially when adopting a fire and forget approach.

In this post, we will explore the nuances of making network calls, particularly when sending emails without waiting for a response. Do we use methods with Task.Run, or do we let them run freely? Let's break it down step by step.

The Problem with Sending Emails Asynchronously

In many projects, the common requirement is to send emails in response to user actions. However, when sending an email, we often do not want to wait for that operation to complete, given that most email services operate using background queues. This raises an important question:

How can we execute the email sending process asynchronously without blocking our main thread?

Understanding Email Sending Mechanism

Most email providers function using a queueing system. When you send a request to send an email:

The request is placed into a queue.

The email provider then processes these requests in the background.

Thus, an API like SendEmailAsync is essentially saying, "please accept my request to send this email," rather than promising immediate delivery.

Comparing the Two Methods

In the context of implementing a fire and forget functionality, let's analyze two approached methods.

Method 1: Using await SendAsync with Task.Run

[[See Video to Reveal this Text or Code Snippet]]

Pros:

By using Task.Run, we can run background tasks without blocking the main thread.

Cons:

Still awaits "SendAsync", which is unnecessary for true fire-and-forget behavior.

The method provides little guarantee that the task will not be lost during the process.

Method 2: Not Awaiting SendAsync

[[See Video to Reveal this Text or Code Snippet]]

Pros:

This method truly represents fire and forget, as it does not await the SendAsync method.

Cons:

If SendAsync fails or encounters an error, there is no way to capture that. The user would never know if the email was attempted or not.

A Better Approach

While both methods show the ability to send emails asynchronously, neither is ideal for ensuring that you will not lose requests. Instead of implementing fire-and-forget directly, consider the following:

Always Await the Email Sending: This ensures that the process is tracked, and any errors encountered can be logged or addressed appropriately.

[[See Video to Reveal this Text or Code Snippet]]

When to Use Fire-and-Forget

If your specific email provider does not use queues, you may create your own queue (using services like Azure Storage Queue, Amazon SQS, or RabbitMQ) and offload the message sending to a separate background processing system (like Azure Functions or AWS Lambda).

Queueing options include:

Azure Storage Queue

Amazon SQS

RabbitMQ

Conclusion

While fire and forget methods seem appealing, they can often lead to unmonitored failures or loss of important requests, especially with processes like sending emails. The recommended approach is to always ensure you adequately handle asynchronous operations for reliability.

In summary, if you're crafting your asynchronous email sending logic:

Always await your tasks to ensure successful completion.

Consider using external queues to manage tasks appropriately.

Focus on reliability and user experience; your users will appreciate services that work seamlessly.

By implementing these strategies, you're ensuring that your applications are robust and maintain