Laravel 响应准备

摘要：响应准备若不是的对象，则构造成此对象类型本质就是用的类构建响应准备主要是设置响应头信息类设置编码格式若传输时用分块编码，则移除因为采用分块编码时可以知道传输何时完成

public function prepareResponse($request, $response)
{
    if ($response instanceof PsrResponseInterface) {
        $response = (new HttpFoundationFactory)->createResponse($response);
    }
    // 若不是 SymfonyComponentHttpFoundationSymfonyResponse 的对象，则构造成此对象
    elseif (! $response instanceof SymfonyResponse) {
        $response = new Response($response);
    }

    return $response->prepare($request);
}

public function createResponse(ResponseInterface $psrResponse)
{
    $response = new Response(
        $psrResponse->getBody()->__toString(),
        $psrResponse->getStatusCode(),
        $psrResponse->getHeaders()
    );
    $response->setProtocolVersion($psrResponse->getProtocolVersion());

    foreach ($psrResponse->getHeader("Set-Cookie") as $cookie) {
        $response->headers->setCookie($this->createCookie($cookie));
    }

    return $response;
}

本质就是用的 Response 类

public function __construct($content = "", $status = 200, $headers = array())
{
    $this->headers = new ResponseHeaderBag($headers);
    $this->setContent($content);
    $this->setStatusCode($status);
    $this->setProtocolVersion("1.0");

    // Deprecations
    $class = get_class($this);
    if ($this instanceof PHPUnit_Framework_MockObject_MockObject || $this instanceof ProphecyDoublerDoubleInterface) {
        $class = get_parent_class($class);
    }
    if (isset(self::$deprecationsTriggered[$class])) {
        return;
    }

    self::$deprecationsTriggered[$class] = true;
    foreach (self::$deprecatedMethods as $method) {
        $r = new ReflectionMethod($class, $method);
        if (__CLASS__ !== $r->getDeclaringClass()->getName()) {
            @trigger_error(sprintf("Extending %s::%s() in %s is deprecated since version 3.2 and won"t be supported anymore in 4.0 as it will be final.", __CLASS__, $method, $class), E_USER_DEPRECATED);
        }
    }
}
public function setContent($content)
{
    if (null !== $content && !is_string($content) && !is_numeric($content) && !is_callable(array($content, "__toString"))) {
        throw new UnexpectedValueException(sprintf("The Response content must be a string or object implementing __toString(), "%s" given.", gettype($content)));
    }

    $this->content = (string) $content;

    return $this;
}
public function setStatusCode($code, $text = null)
{
    $this->statusCode = $code = (int) $code;
    if ($this->isInvalid()) {
        throw new InvalidArgumentException(sprintf("The HTTP status code "%s" is not valid.", $code));
    }

    if (null === $text) {
        $this->statusText = isset(self::$statusTexts[$code]) ? self::$statusTexts[$code] : "unknown status";

        return $this;
    }

    if (false === $text) {
        $this->statusText = "";

        return $this;
    }

    $this->statusText = $text;

    return $this;
}
public function isInvalid()
{
    return $this->statusCode < 100 || $this->statusCode >= 600;
}
public function setProtocolVersion($version)
{
    $this->version = $version;

    return $this;
}

主要是设置响应头

public function prepare(Request $request)
{
    $headers = $this->headers;
    // 信息类
    if ($this->isInformational() || $this->isEmpty()) {
        $this->setContent(null);
        $headers->remove("Content-Type");
        $headers->remove("Content-Length");
    } else {
        if (!$headers->has("Content-Type")) {
            $format = $request->getRequestFormat();
            # static::$formats = array(
            #    "html" => array("text/html", "application/xhtml+xml"),
            #    "txt" => array("text/plain"),
            #    "js" => array("application/javascript", "application/x-javascript", "text/javascript"),
            #    "css" => array("text/css"),
            #    "json" => array("application/json", "application/x-json"),
            #    "xml" => array("text/xml", "application/xml", "application/x-xml"),
            #    "rdf" => array("application/rdf+xml"),
            #    "atom" => array("application/atom+xml"),
            #    "rss" => array("application/rss+xml"),
            #    "form" => array("application/x-www-form-urlencoded"),
            # );
            if (null !== $format && $mimeType = $request->getMimeType($format)) {
                $headers->set("Content-Type", $mimeType);
            }
        }
        // 设置编码格式
        $charset = $this->charset ?: "UTF-8";
        if (!$headers->has("Content-Type")) {
            $headers->set("Content-Type", "text/html; charset=".$charset);
        } elseif (0 === stripos($headers->get("Content-Type"), "text/") && false === stripos($headers->get("Content-Type"), "charset")) {
            $headers->set("Content-Type", $headers->get("Content-Type")."; charset=".$charset);
        }
        // 若传输时用分块编码，则移除 Content-Length, 因为采用分块编码时可以知道传输何时完成
        if ($headers->has("Transfer-Encoding")) {
            $headers->remove("Content-Length");
        }

        if ($request->isMethod("HEAD")) {
            $length = $headers->get("Content-Length");
            $this->setContent(null);
            if ($length) {
                $headers->set("Content-Length", $length);
            }
        }
    }

    if ("HTTP/1.0" != $request->server->get("SERVER_PROTOCOL")) {
        $this->setProtocolVersion("1.1");
    }

    if ("1.0" == $this->getProtocolVersion() && false !== strpos($this->headers->get("Cache-Control"), "no-cache")) {
        $this->headers->set("pragma", "no-cache");
        $this->headers->set("expires", -1);
    }

    $this->ensureIEOverSSLCompatibility($request);

    return $this;
}
public function isInformational()
{
    return $this->statusCode >= 100 && $this->statusCode < 200;
}
protected function ensureIEOverSSLCompatibility(Request $request)
{
    if (false !== stripos($this->headers->get("Content-Disposition"), "attachment") && preg_match("/MSIE (.*?);/i", $request->server->get("HTTP_USER_AGENT"), $match) == 1 && true === $request->isSecure()) {
        if ((int) preg_replace("/(MSIE )(.*?);/", "$2", $match[0]) < 9) {
            $this->headers->remove("Cache-Control");
        }
    }
}