What is the best way to handle HTTP timeouts?

1 Causes of HTTP timeouts

HTTP timeouts can occur for various reasons, such as network congestion, server overload, firewall blocking, or slow processing. Sometimes, the timeout is intentional, as the server or the client sets a limit on how long they are willing to wait for a response. This limit is called the timeout value, and it can vary depending on the type and purpose of the request. For example, a GET request for a web page might have a longer timeout value than a POST request for a form submission.

2 Prevention of HTTP timeouts

The best way to avoid HTTP timeouts is to optimize the performance and reliability of your web application. This means reducing the size and complexity of your requests and responses, using caching and compression techniques, and implementing load balancing and failover mechanisms. You should also monitor your network and server resources, and adjust your timeout values accordingly. For example, you can use a shorter timeout value for requests that are not critical, and a longer timeout value for requests that are essential.

3 Handling of HTTP timeouts

Even with the best practices, you cannot completely eliminate the possibility of HTTP timeouts. Therefore, you need to have a strategy to handle them gracefully, and inform your users about the status of their requests. There are two main approaches to handle HTTP timeouts: retrying and canceling. Retrying means sending the same request again, hoping that the server will respond this time. Canceling means giving up on the request, and returning an error message to the user. Both approaches have pros and cons, depending on the context and the expected outcome of the request.

4 Retrying HTTP timeouts

Retrying HTTP timeouts can be useful when the request is idempotent, meaning that it does not change the state of the server or the data. For example, a GET request for a web page is idempotent, because it only retrieves information, and does not modify anything. Retrying can also be helpful when the request is important, and the user is willing to wait for a longer time. However, retrying has some drawbacks, such as consuming more network and server resources, and potentially creating duplicate or inconsistent data. Therefore, you should use retrying with caution, and limit the number and frequency of retries.

5 Canceling HTTP timeouts

Canceling HTTP timeouts can be preferable when the request is not idempotent, meaning that it does change the state of the server or the data. For example, a POST request for a form submission is not idempotent, because it creates or updates information, and may have side effects. Canceling can also be advisable when the request is not essential, and the user is not interested in waiting for a longer time. However, canceling has some disadvantages, such as losing the data or the progress of the request, and frustrating the user. Therefore, you should use canceling with care, and provide a clear and friendly error message to the user.

6 Best practices for HTTP timeouts

When dealing with HTTP timeouts, there is no one-size-fits-all solution. However, there are general best practices you can use to improve your web application's user experience and reliability. This includes selecting appropriate timeout values based on the type, purpose, and priority of requests, optimizing requests and responses through caching, compression, and pagination, implementing retry logic with exponential backoff, jitter, and circuit breaker, and implementing cancel logic with abort signals, promises, and callbacks. Additionally, you should provide feedback to users with spinners, progress bars, and notifications. Lastly, handle errors gracefully with messages like "Sorry, something went wrong. Please try again later." or "Your request has been canceled. Please start over." By following these best practices you can ensure your web application delivers a smooth and satisfying service to your users.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?