PSR
PSR-7、PSR-17和PSR-18的引入都是计划的一部分，以使
构建需要以与 HTTP 客户端无关的方式向服务器发送 HTTP 请求的应用程序
我一直在使用许多过去严重依赖 Guzzle 而不是抽象接口的应用程序。这些应用程序中的大多数使用包含 JSON 正文的 GET 或 POST 请求发出简单的 API 请求，响应也包含 JSON 正文或抛出 HTTP 4xx 或 5xx 错误的异常。
API 包装器
这个问题来自最近的一个项目，我尝试开发一个 API 包，该包没有明确依赖 Guzzle，而是仅依赖于 PSR 接口。
这个想法是创建一个ApiWrapper可以使用以下方法启动的类：
- 满足 PSR-18的HTTP 客户端
ClientInterface - 满足 PSR-17的请求工厂
RequestFactoryInterface - 满足 PSR-17的流工厂
StreamFactoryInterface
这个类将有它需要的任何东西：
- 使用请求工厂和流工厂发出请求 (PSR-7)
- 使用HTTP 客户端发送请求
- 处理响应 - 因为我们知道这将满足 PSR-7
ResponseInterface
这样的 API 包装器不依赖于上述接口的任何具体实现，而只需要这些接口的任何实现。因此，开发人员将能够使用他或她最喜欢的 HTTP 客户端，而不是被迫使用像 Guzzle 这样的特定客户端。
问题
现在，首先，我真的很喜欢 Guzzle，这不是一篇文章来质疑 Guzzle 的厉害之处，这只是一篇询问如何让开发人员能够根据自己的需要选择正确的 http 客户端的文章。
但问题是显式依赖 Guzzle 提供了很多不错的功能，因为 Guzzle 所做的比上述更多。Guzzle 还应用了一系列处理程序和中间件，例如跟踪重定向或为 HTTP 4xx 响应引发异常。
问题
描述很长，但问题来了：如何处理常见的 HTTP 请求处理，例如以受控方式跟踪重定向或抛出 HTTP 4xx 响应的异常（因此无论使用何种 HTTP 客户端都会产生相同的响应），而无需准确指定使用什么 HTTP 客户端？
例子
下面是一个ApiWrapper实现示例：
<?php
use Psr\Http\Client\ClientExceptionInterface;
use Psr\Http\Client\ClientInterface;
use Psr\Http\Message\RequestFactoryInterface;
use Psr\Http\Message\RequestInterface;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\StreamFactoryInterface;
use Psr\Http\Message\StreamInterface;
/*
* API Wrapper using PSR-18 ClientInterface, PSR-17 RequestFactoryInterface and PSR-7 RequestInterface
*
* Inspired from: https://www.php-fig.org/blog/2018/11/psr-18-the-php-standard-for-http-clients/
* Require the packages `psr/http-client` and `psr/http-factory`
*
* Details about PSR-7 taken from https://www.dotkernel.com/dotkernel3/what-is-psr-7-and-how-to-use-it/
*
* Class Name Description
* Psr\Http\Message\MessageInterface Representation of a HTTP message
* Psr\Http\Message\RequestInterface Representation of an outgoing, client-side request.
* Psr\Http\Message\ServerRequestInterface Representation of an incoming, server-side HTTP request.
* Psr\Http\Message\ResponseInterface Representation of an outgoing, server-side response.
* Psr\Http\Message\StreamInterface Describes a data stream
* Psr\Http\Message\UriInterface Value object representing a URI.
* Psr\Http\Message\UploadedFileInterface Value object representing a file uploaded through an HTTP request.
*/
class ApiWrapper
{
/**
* The PSR-18 compliant ClientInterface.
*
* @var ClientInterface
*/
private $psr18HttpClient;
/**
* The PSR-17 compliant RequestFactoryInterface.
*
* @var RequestFactoryInterface
*/
private $psr17HttpRequestFactory;
/**
* The PSR-17 compliant StreamFactoryInterface.
*
* @var StreamFactoryInterface
*/
private $psr17HttpStreamFactory;
public function __construct(
ClientInterface $psr18HttpClient,
RequestFactoryInterface $psr17HttpRequestFactory,
StreamFactoryInterface $psr17HttpStreamFactory,
array $options = []
) {
$this->psr18HttpClient($psr18HttpClient);
$this->setPsr17HttpRequestFactory($psr17HttpRequestFactory);
$this->setPsr17HttpStreamFactory($psr17HttpStreamFactory);
}
public function psr18HttpClient(ClientInterface $psr18HttpClient): void
{
$this->psr18HttpClient = $psr18HttpClient;
}
public function setPsr17HttpRequestFactory(RequestFactoryInterface $psr17HttpRequestFactory): void
{
$this->psr17HttpRequestFactory = $psr17HttpRequestFactory;
}
public function setPsr17HttpStreamFactory(StreamFactoryInterface $psr17HttpStreamFactory): void
{
$this->psr17HttpStreamFactory = $psr17HttpStreamFactory;
}
public function makeRequest(string $method, $uri, ?array $headers = [], ?string $body = null): RequestInterface
{
$request = $this->psr17HttpRequestFactory->createRequest($method, $uri);
if (! empty($headers)) {
$request = $this->addHeadersToRequest($request, $headers);
}
if (! empty($body)) {
$stream = $this->createStreamFromString($body);
$request = $this->addStreamToRequest($request, $stream);
}
return $request;
}
/**
* Add headers provided as nested array.
*
* Format of headers:
* [
* 'accept' => [
* 'text/html',
* 'application/xhtml+xml',
* ],
* ]
* results in the header: accept:text/html, application/xhtml+xml
* See more details here: https://www.php-fig.org/psr/psr-7/#headers-with-multiple-values
*
* @param \Psr\Http\Message\RequestInterface $request
* @param array $headers
* @return \Psr\Http\Message\RequestInterface
*/
public function addHeadersToRequest(RequestInterface $request, array $headers): RequestInterface
{
foreach ($headers as $headerKey => $headerValue) {
if (is_array($headerValue)) {
foreach ($headerValue as $key => $value) {
if ($key == 0) {
$request->withHeader($headerKey, $value);
} else {
$request->withAddedHeader($headerKey, $value);
}
}
} else {
$request->withHeader($headerKey, $headerValue);
}
}
return $request;
}
/**
* Use the PSR-7 complient StreamFactory to create a stream from a simple string.
*
* @param string $body
* @return \Psr\Http\Message\StreamInterface
*/
public function createStreamFromString(string $body): StreamInterface
{
return $this->psr17HttpStreamFactory->createStream($body);
}
/**
* Add a PSR 7 Stream to a PSR 7 Request.
*
* @param \Psr\Http\Message\RequestInterface $request
* @param \Psr\Http\Message\StreamInterface $body
* @return \Psr\Http\Message\RequestInterface
*/
public function addStreamToRequest(RequestInterface $request, StreamInterface $body): RequestInterface
{
return $request->withBody($body);
}
/**
* Make the actual HTTP request.
*
* @param \Psr\Http\Message\RequestInterface $request
* @return \Psr\Http\Message\ResponseInterface
* @throws \Psr\Http\Client\ClientExceptionInterface
*/
public function request(RequestInterface $request): ResponseInterface
{
// According to PSR-18:
// A Client MUST throw an instance of Psr\Http\Client\ClientExceptionInterface
// if and only if it is unable to send the HTTP request at all or if the
// HTTP response could not be parsed into a PSR-7 response object.
return $this->psr18HttpClient->sendRequest($request);
}
}