Boosting Performance with Symfony HttpClient and Parallel Requests

[Lomanu4]

? This article is an English translation of the original French version available here:

Пожалуйста Авторизируйтесь или Зарегистрируйтесь для просмотра скрытого текста.

When developing a Symfony application that communicates with multiple APIs, it's tempting to send requests one after another. However, this approach can quickly become a bottleneck.

Fortunately, Symfony’s HttpClient component makes it easy to manage multiple parallel requests — without threads, promises, or workers.

In this article, I’ll show you how to take advantage of this feature to improve performance.

The Classic Problem: Sequential API Calls


Let’s take a simple example. You need to query 5 APIs to retrieve and merge data. Most developers would instinctively write something like this:


$results = [];

foreach ($urls as $url) {
$response = $client->request('GET', $url);
$results[] = $response->toArray();
}

This code works, but it’s slow: each request waits for the previous one to complete before starting.

The Solution: stream() for Concurrent Requests


Symfony provides a more powerful API with the stream() method. It allows you to fire off all requests at once and process responses as soon as they’re ready — avoiding unnecessary blocking.

Here’s how:


$responses = [];

foreach ($urls as $url) {
$responses[] = $client->request('GET', $url);
}

// Read responses as they come in
foreach ($client->stream($responses) as $response => $chunk) {
if ($chunk->isLast()) {
$result = $response->toArray();
// Process the result
}
}

This code:

• sends all requests in parallel
• processes each response as soon as it’s complete
• significantly reduces total execution time

Performance Gains


Gains depend on your target APIs, but in many cases, you can cut total response time by a factor of 2 to 10, especially when APIs take 300 to 500 ms to respond individually.

When to Use This Method


Use stream() whenever you have:

• multiple independent API calls to make
• simple response processing logic
• slow or numerous third-party APIs

In Summary


Symfony HttpClient allows you to write simple, readable, and asynchronous code without adding unnecessary technical complexity.

The stream() method is a powerful tool to add to your toolbox for any API-driven Symfony project.

Go Further


To explore the full capabilities of HttpClient and stream(), check out the

Пожалуйста Авторизируйтесь или Зарегистрируйтесь для просмотра скрытого текста.

.

What About You?


Have you already used stream() in your Symfony projects?

Share your feedback or tips with me on

Пожалуйста Авторизируйтесь или Зарегистрируйтесь для просмотра скрытого текста.

— I’d love to chat!

Пожалуйста Авторизируйтесь или Зарегистрируйтесь для просмотра скрытого текста.