hyperf 中 http 设置响应头为 text/event-stream_hyperf 设置响应头

在hyperf中 设置响应头让后端直接给前端返回 event-stream 流的需求，发现hyperf 中在重写 SwooleConnection 时，设置的属性 $response 为 protected ，不能直接调用此属性。

为了让我能设置此响应头，我 继承了 Hyperf\HttpServer\Server 类 并重写了  onRequest 方法，

具体的做法如下：

首先创建StreamServer 类， 并重写了onRequest 方法，如果只是想某几个路由 重写，需要自己写一下配置

<?php
 
 
namespace App\Service\Server;
 
 
use Hyperf\Dispatcher\HttpDispatcher;
use Hyperf\ExceptionHandler\ExceptionHandlerDispatcher;
use Hyperf\HttpServer\ResponseEmitter;
use Hyperf\HttpServer\Server;
use Psr\Container\ContainerInterface;
use Swoole\Http\Request;
use Swoole\Http\Response;
 
class StreamServer extends Server
{
    const STREAM_URL = [
        '/chat/chat/test'
    ];
    public function __construct(ContainerInterface $container, HttpDispatcher $dispatcher, ExceptionHandlerDispatcher $exceptionHandlerDispatcher, ResponseEmitter $responseEmitter)
    {
        parent::__construct($container, $dispatcher, $exceptionHandlerDispatcher, $responseEmitter);
    }
 
    /**
     * @param Request $request
     * @param Response $response
     */
    public function onRequest($request, $response): void
    {
        $pathInfo = $request->server['path_info'];
        if (in_array($pathInfo, self::STREAM_URL)) {
            $response->header('Content-Type', 'text/event-stream');
            $response->header('Cache-Control', 'no-cache');
            $response->header('Connection', 'keep-alive');
        }
        parent::onRequest($request, $response);
    }
}

然后再将 config/autoload/server.php 中的 http 配置 修改，如下图

这样，我们在控制器里面就可以实现 response 的header 更改为 text/event-stream。

<?php
 
use Hyperf\HttpServer\Contract\ResponseInterface;
 
 $wrResponse = ApplicationContext::getContainer()->get(ResponseInterface::class);
 
//此处可以将返回的数据 直接打印字屏幕上
 $wrResponse->write("data: " . $res . "\n\n");

 也就实现了 chatgpt 的打印流的关键步骤，下面贴出部分代码，使用guzzlehttp 处理chatgpt 返回的流式数据

 
use GuzzleHttp\Client;
use GuzzleHttp\Psr7\Utils;
use Hyperf\Guzzle\ClientFactory;
use Hyperf\HttpServer\Contract\ResponseInterface;
use Hyperf\Utils\ApplicationContext;
use Hyperf\Context\Context;
 
class HttpRequestService
{
 
 
 
    private $clientFactory;
 
    //此处可以模拟类属性,获取协程中的属性
     public function __get($key)
    {
        $className = static::class;
        $key = env('APP_NAME').$className . $key;
        return Context::get($key);
    }
 
   //此处可以模拟类属性,将属性存在协程中
    public function __set($key, $value)
    {
        $className = static::class;
        $key = env('APP_NAME').$className . $key;
        Context::set($key, $value);
    }
 
    public function __construct()
    {
        $this->clientFactory = make(ClientFactory::class);
    }
 /**
     * 是否使用流式获取
     * @param bool $stream
     * @return $this
     */
    private function setStream($stream = false)
    {
        $this->stream = $stream;
        return $this;
    }
 
 
/**
     * 初始化
     * @param string $domainUrl
     * @param array $header
     * @param int $timeout
     */
    private function init($domainUrl = '', $header = [], $timeout = 120)
    {
        $config = ['timeout' => $timeout];
 
        if (!empty($domainUrl)) {
            $config['base_uri'] = $domainUrl;
        }
 
        if ($this->stream) {
            $config['stream'] = true;
        }
 
        if (!empty($header) && is_array($header)) {
            $config = array_merge($config, ['headers' => $header]);
        }
        /** @var Client $client */
        $this->client = $this->clientFactory->create($config);
    }
 
    public function postStream($domain, $uri, $params, $header = [])
    {
        $this->setStream(true);
        $this->init($domain, $header);
        $type          = 'json';
        $requestParmas = [$type => $params];
 
        $response     = $this->client->post($uri, $requestParmas);
        $responseData = $response->getBody(); //获取流数据
        $parseData    = [];
        $wrResponse = ApplicationContext::getContainer()->get(ResponseInterface::class);
        while (!$responseData->eof()) {
            $res = trim(Utils::readLine($responseData)); //一行一行读取
            $res = str_replace("data: ", "", $res);
            if (empty($res)) {
                continue;
            }
            $wrResponse->write("data: " . $res . "\n\n");
            if ($res == '[DONE]') {
                break;
            }
            //休眠时间，用于前端展示
            usleep(100000);
            $res = json_decode($res, true);
            if (!empty($res)) {
                $parseData[] = $res['choices'][0]['delta']['content'] ?? ($res['choices'][0]['delta']['role'] ?? '');
            }
        }
 
        return $parseData;
    }
}