Use Swoole to encapsulate a highly reliable asynchronous HTTP client

As web applications continue to develop, the need for HTTP clients is becoming more and more important, especially when data is requested across the network. In traditional PHP implementation, it is a common way to use libraries such as cURL to make network requests, but it does not support asynchronous requests, resulting in performance limitations when a large number of concurrent requests occur.

Swoole is a coroutine network communication engine based on PHP. It provides an asynchronous request method that can greatly improve the performance of applications. This article will introduce how to use Swoole to encapsulate a highly reliable asynchronous HTTP client.

Why use Swoole asynchronous HTTP client

When concurrent requests are made, the synchronous HTTP client will cause a performance bottleneck, while the asynchronous HTTP client can handle multiple requests simultaneously in a single process. request. Swoole provides a coroutine model to implement asynchronous requests without switching processes. It can also reduce memory usage and TCP connection overhead, and improve application performance.

Using Swoole asynchronous HTTP client also has the following benefits:

• Provides rich event callback functions, which can perform corresponding processing operations when the request succeeds or fails;
• Automatically handles the request headers, response headers and response content of HTTP requests, making it easier for developers to use;
• Integrated connection pool management, which can automatically manage TCP connections under high concurrency.

Writing an asynchronous HTTP client

Before you start writing an asynchronous HTTP client, you need to install the Swoole extension and ensure that the PHP version is 7.0 or above. To install the extension, use the following command:

pecl install swoole

Then add the following content to the PHP configuration file:

extension=swoole.so

Next, we can start writing the code for the asynchronous HTTP client. First, we need to define a HttpClient class for initiating asynchronous HTTP requests. The specific code is as follows:

class HttpClient
{
    private $client;

    public function __construct($host, $port = 80, $ssl = false)
    {
        $scheme = $ssl ? 'https://' : 'http://';
        $this->client = new SwooleCoroutineHttpClient($host, $port, $ssl);
        $this->client->setHeaders([
            'User-Agent' => 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3',
            'Accept' => 'text/html,application/xhtml+xml,application/xml',
            'Accept-Encoding' => 'gzip',
        ]);
    }

    public async function get($path, $params = [])
    {
        $path .= '?' . http_build_query($params);
        return $this->request('GET', $path);
    }

    public async function post($path, $params = [])
    {
        return $this->request('POST', $path, $params);
    }

    private async function request($method, $path, $params = [])
    {
        $this->client->setMethod($method);
        $this->client->setData($params);
        $this->client->execute($path);

        $statusCode = $this->client->statusCode;
        $body = $this->client->body;

        if ($statusCode !== 200) {
            throw new RuntimeException(sprintf('Request failed with status code %d', $statusCode));
        }

        return $body;
    }
}

In the above code, we initialize a Swoole's HttpClient object through the __construct method. Since we need to support both HTTP and HTTPS protocols, we need to determine the protocol of the URL and then set the corresponding port number and SSL options.

Then we implemented asynchronous HTTP requests through the get and post methods. In the request, we use the http_build_query function to convert the parameters into a string in URL form and splice the parameters in the URL. Then we set the request method and parameters in the $client object, and finally call the $client->execute method to initiate the request.

Use the $client->execute method to initiate a request. Swoole will automatically coordinate the request and response and wait for the response to arrive. After the response arrives, we can obtain the status code and response body of the response, and then determine whether the request was successful based on the status code.

Usage Example

To demonstrate how to use the above asynchronous HTTP client, we have written a simple example. The code is as follows:

$client = new HttpClient('httpbin.org');

go(function () use ($client) {
    $result = yield $client->get('/get', ['hello' => 'world']);
    var_dump($result);
});

go(function () use ($client) {
    $result = yield $client->post('/post', ['name' => 'Jack', 'age' => 29]);
    var_dump($result);
});

In the above code, we first initialize a HttpClient object and set the remote host address. Then we initiated two asynchronous requests through the go coroutine, one was a GET request and the other was a POST request, with parameters ['hello' => 'world']and['name' => 'Jack', 'age' => 29]. After each asynchronous request is completed, we output the response body content through var_dump.

Summary

This article introduces how to use Swoole to encapsulate a highly reliable asynchronous HTTP client to support concurrent requests. By using Swoole, we can easily implement coroutine asynchronous requests and avoid the performance bottleneck of concurrent requests in traditional PHP applications.

The above is the detailed content of Use Swoole to encapsulate a highly reliable asynchronous HTTP client. For more information, please follow other related articles on the PHP Chinese website!