ServerRequestTrait.php

PHP

Path: src/Http/Message/ServerRequestTrait.php

<?php
namespace mini\Http\Message;

use Psr\Http\Message\{
    ServerRequestInterface,
    UploadedFileInterface,
    StreamInterface,
    UriInterface
};

/**
 * Representation of an incoming, server-side HTTP request.
 *
 * Per the HTTP specification, this interface includes properties for
 * each of the following:
 *
 * - Protocol version
 * - HTTP method
 * - URI
 * - Headers
 * - Message body
 *
 * Additionally, it encapsulates all data as it has arrived at the
 * application from the CGI and/or PHP environment, including:
 *
 * - The values represented in $_SERVER.
 * - Any cookies provided (generally via $_COOKIE)
 * - Query string arguments (generally via $_GET, or as parsed via parse_str())
 * - Upload files, if any (as represented by $_FILES)
 * - Deserialized body parameters (generally from $_POST)
 *
 * $_SERVER values MUST be treated as immutable, as they represent application
 * state at the time of request; as such, no methods are provided to allow
 * modification of those values. The other values provide such methods, as they
 * can be restored from $_SERVER or the request body, and may need treatment
 * during the application (e.g., body parameters may be deserialized based on
 * content type).
 *
 * Additionally, this interface recognizes the utility of introspecting a
 * request to derive and match additional parameters (e.g., via URI path
 * matching, decrypting cookie values, deserializing non-form-encoded body
 * content, matching authorization headers to users, etc). These parameters
 * are stored in an "attributes" property.
 *
 * Requests are considered immutable; all methods that might change state MUST
 * be implemented such that they retain the internal state of the current
 * message and return an instance that contains the changed state.
 */
trait ServerRequestTrait {
    use RequestTrait;

    protected array $serverParams = [];
    protected array $cookieParams = [];
    protected ?array $queryParams = null;
    protected array $uploadedFiles = [];
    protected mixed $parsedBody = null;
    protected array $attributes = [];

    /**
     * Construct a ServerRequest instance.
     *
     * @param string $method                            Case-sensitive method.
     * @param string $requestTarget                     Request target (e.g., "/path?query=value")
     * @param string|resource|StreamInterface $body     Body
     * @param array $headers                            Array of header names => values
     * @param array|null $queryParams                   Query params override (null = derive from request target)
     * @param array $serverParams                       Array of server params like $_SERVER
     * @param array $cookieParams                       Array of cookie params like $_COOKIE
     * @param UploadedFileInterface[] $uploadedFiles    Array of uploaded file instances
     * @param null|object|array $parsedBody             Deserialized body data, typically an object or array.
     * @param array $attributes                         Attributes derived from the request
     * @param string $protocolVersion                   The HTTP protocol version, typically "1.1" or "1.0"
     */
    protected function ServerRequestTrait(
        string $method,
        string $requestTarget,
        mixed $body,
        array $headers=[],
        ?array $queryParams=null,
        array $serverParams=[],
        array $cookieParams=[],
        array $uploadedFiles=[],
        mixed $parsedBody=null,
        array $attributes=[],
        string $protocolVersion="1.1"
    ) {
        if (!self::isValidUploadedFilesArray($uploadedFiles)) {
            self::throwInvalidUploadedFilesArray();
        }
        $this->RequestTrait($method, $requestTarget, $body, $headers, $protocolVersion);
        if ($queryParams !== null) {
            $this->queryParams = self::fixQueryParams($queryParams);
        }
        $this->serverParams = $serverParams;
        $this->cookieParams = $cookieParams;
        $this->uploadedFiles = $uploadedFiles;
        $this->parsedBody = $parsedBody;
        $this->attributes = $attributes;
    }

    public function __clone() {
        if (is_object($this->parsedBody)) {
            $this->parsedBody = clone $this->parsedBody;
        }
    }

    /**
     * Retrieves the URI instance with HTTPS detection from server params.
     *
     * Overrides parent getUri() to add scheme detection from server params.
     * If HTTPS server param is 'on' or '1', uses https:// scheme, else http://.
     *
     * @return UriInterface
     */
    public function getUri(): UriInterface {
        if ($this->uriOverride !== null) {
            return $this->uriOverride;
        }

        // Construct from request target + headers
        $uri = $this->requestTarget;

        // Add scheme and host if Host header exists
        if ($host = $this->getHeaderLine('Host')) {
            // Detect HTTPS from server params
            $scheme = 'http';
            if (isset($this->serverParams['HTTPS']) &&
                ($this->serverParams['HTTPS'] === 'on' || $this->serverParams['HTTPS'] === '1')) {
                $scheme = 'https';
            }
            $uri = "{$scheme}://{$host}{$this->requestTarget}";
        }
        // else: return relative URI (just request target)

        return new Uri($uri);
    }

    /**
     * Retrieve server parameters.
     *
     * Retrieves data related to the incoming request environment,
     * typically derived from PHP's $_SERVER superglobal. The data IS NOT
     * REQUIRED to originate from $_SERVER.
     *
     * @return array
     */
    public function getServerParams(): array {
        return $this->serverParams;
    }

    /**
     * Retrieve cookies.
     *
     * Retrieves cookies sent by the client to the server.
     *
     * The data MUST be compatible with the structure of the $_COOKIE
     * superglobal.
     *
     * @return array
     */
    public function getCookieParams(): array {
        return $this->cookieParams;
    }

    /**
     * Return an instance with the specified cookies.
     *
     * The data IS NOT REQUIRED to come from the $_COOKIE superglobal, but MUST
     * be compatible with the structure of $_COOKIE. Typically, this data will
     * be injected at instantiation.
     *
     * This method MUST NOT update the related Cookie header of the request
     * instance, nor related values in the server params.
     *
     * This method MUST be implemented in such a way as to retain the
     * immutability of the message, and MUST return an instance that has the
     * updated cookie values.
     *
     * @param array $cookies Array of key/value pairs representing cookies.
     * @return static
     */
    public function withCookieParams(array $cookies): ServerRequestInterface {
        $c = clone $this;
        $c->cookieParams = $cookies;
        return $c;
    }

    /**
     * Retrieve query string arguments.
     *
     * Retrieves the deserialized query string arguments, if any.
     *
     * If query params were overridden via withQueryParams(), returns those.
     * Otherwise, derives query params from the request target.
     *
     * Note: the query params might not be in sync with the URI or server
     * params. If you need to ensure you are only getting the original
     * values, you may need to parse the query string from `getUri()->getQuery()`
     * or from the `QUERY_STRING` server param.
     *
     * @return array
     */
    public function getQueryParams(): array {
        if ($this->queryParams !== null) {
            return $this->queryParams;
        }

        // Derive from request target
        $query = $this->getQuery();
        if ($query === '') {
            return [];
        }

        $params = [];
        parse_str($query, $params);
        return $params;
    }

    /**
     * Return an instance with the specified query string arguments.
     *
     * These values SHOULD remain immutable over the course of the incoming
     * request. They MAY be injected during instantiation, such as from PHP's
     * $_GET superglobal, or MAY be derived from some other value such as the
     * URI. In cases where the arguments are parsed from the URI, the data
     * MUST be compatible with what PHP's parse_str() would return for
     * purposes of how duplicate query parameters are handled, and how nested
     * sets are handled.
     *
     * Setting query string arguments MUST NOT change the URI stored by the
     * request, nor the values in the server params.
     *
     * This method MUST be implemented in such a way as to retain the
     * immutability of the message, and MUST return an instance that has the
     * updated query string arguments.
     *
     * @param array $query Array of query string arguments, typically from
     *     $_GET.
     * @return static
     */
    public function withQueryParams(array $query): ServerRequestInterface {
        $c = clone $this;
        $c->queryParams = $query;
        return $c;
    }

    /**
     * Retrieve normalized file upload data.
     *
     * This method returns upload metadata in a normalized tree, with each leaf
     * an instance of Psr\Http\Message\UploadedFileInterface.
     *
     * These values MAY be prepared from $_FILES or the message body during
     * instantiation, or MAY be injected via withUploadedFiles().
     *
     * @return array An array tree of UploadedFileInterface instances; an empty
     *     array MUST be returned if no data is present.
     */
    public function getUploadedFiles(): array {
        return $this->uploadedFiles;
    }

    /**
     * Create a new instance with the specified uploaded files.
     *
     * This method MUST be implemented in such a way as to retain the
     * immutability of the message, and MUST return an instance that has the
     * updated body parameters.
     *
     * @param array $uploadedFiles An array tree of UploadedFileInterface instances.
     * @return static
     * @throws \InvalidArgumentException if an invalid structure is provided.
     */
    public function withUploadedFiles(array $uploadedFiles): ServerRequestInterface {
        if (!self::isValidUploadedFilesArray($uploadedFiles)) {
            self::throwInvalidUploadedFiles();
        }
        $c = clone $this;
        $c->uploadedFiles = $uploadedFiles;
        return $c;
    }

    /**
     * Retrieve any parameters provided in the request body.
     *
     * If the request Content-Type is either application/x-www-form-urlencoded
     * or multipart/form-data, and the request method is POST, this method MUST
     * return the contents of $_POST.
     *
     * Otherwise, this method may return any results of deserializing
     * the request body content; as parsing returns structured content, the
     * potential types MUST be arrays or objects only. A null value indicates
     * the absence of body content.
     *
     * @return null|array|object The deserialized body parameters, if any.
     *     These will typically be an array or object.
     */
    public function getParsedBody() {
        return $this->parsedBody;
    }

    /**
     * Return an instance with the specified body parameters.
     *
     * These MAY be injected during instantiation.
     *
     * If the request Content-Type is either application/x-www-form-urlencoded
     * or multipart/form-data, and the request method is POST, use this method
     * ONLY to inject the contents of $_POST.
     *
     * The data IS NOT REQUIRED to come from $_POST, but MUST be the results of
     * deserializing the request body content. Deserialization/parsing returns
     * structured data, and, as such, this method ONLY accepts arrays or objects,
     * or a null value if nothing was available to parse.
     *
     * As an example, if content negotiation determines that the request data
     * is a JSON payload, this method could be used to create a request
     * instance with the deserialized parameters.
     *
     * This method MUST be implemented in such a way as to retain the
     * immutability of the message, and MUST return an instance that has the
     * updated body parameters.
     *
     * @param null|array|object $data The deserialized body data. This will
     *     typically be in an array or object.
     * @return static
     * @throws \InvalidArgumentException if an unsupported argument type is
     *     provided.
     */
    public function withParsedBody($data): ServerRequestInterface {
        if ($data !== null && !is_array($data) && !is_object($data)) {
            throw new \InvalidArgumentException("Expecting array, object or NULL");
        }
        $c = clone $this;
        $c->parsedBody = $data;
        return $c;
    }

    /**
     * Retrieve attributes derived from the request.
     *
     * The request "attributes" may be used to allow injection of any
     * parameters derived from the request: e.g., the results of path
     * match operations; the results of decrypting cookies; the results of
     * deserializing non-form-encoded message bodies; etc. Attributes
     * will be application and request specific, and CAN be mutable.
     *
     * @return mixed[] Attributes derived from the request.
     */
    public function getAttributes(): array {
        return $this->attributes;
    }

    /**
     * Retrieve a single derived request attribute.
     *
     * Retrieves a single derived request attribute as described in
     * getAttributes(). If the attribute has not been previously set, returns
     * the default value as provided.
     *
     * This method obviates the need for a hasAttribute() method, as it allows
     * specifying a default value to return if the attribute is not found.
     *
     * @see getAttributes()
     * @param string $name The attribute name.
     * @param mixed $default Default value to return if the attribute does not exist.
     * @return mixed
     */
    public function getAttribute($name, $default = null) {
        return $this->attributes[$name] ?? $default;
    }

    /**
     * Return an instance with the specified derived request attribute.
     *
     * This method allows setting a single derived request attribute as
     * described in getAttributes().
     *
     * This method MUST be implemented in such a way as to retain the
     * immutability of the message, and MUST return an instance that has the
     * updated attribute.
     *
     * @see getAttributes()
     * @param string $name The attribute name.
     * @param mixed $value The value of the attribute.
     * @return static
     */
    public function withAttribute($name, $value): ServerRequestInterface {
        $c = clone $this;
        $c->attributes[$name] = $value;
        return $c;
    }

    /**
     * Return an instance that removes the specified derived request attribute.
     *
     * This method allows removing a single derived request attribute as
     * described in getAttributes().
     *
     * This method MUST be implemented in such a way as to retain the
     * immutability of the message, and MUST return an instance that removes
     * the attribute.
     *
     * @see getAttributes()
     * @param string $name The attribute name.
     * @return static
     */
    public function withoutAttribute($name): ServerRequestInterface {
        $c = clone $this;
        unset($c->attributes[$name]);
        return $c;
    }

    /**
     * Validate an array as per the {@see self::withUploadedFiles()} function.
     */
    protected static function isValidUploadedFilesArray(array $uploadedFiles): bool {
        foreach ($uploadedFiles as $uploadedFile) {
            if (!($uploadedFile instanceof UploadedFileInterface)) {
                return false;
            }
        }
        return true;
    }

    protected static function throwInvalidUploadedFilesArray(): void {
        throw new \InvalidArgumentException("Expecting an array of '".UploadedFileInterface::class."' instances");
    }

    /**
     * Ensures that the passed query params adhere to the shape of
     * query params as they would come from $_GET.
     */
    protected static function fixQueryParams(array $queryParams): array {
        $builtString = http_build_query($queryParams);
        parse_str($builtString, $parsedQueryParams);
        return $parsedQueryParams;
    }
}