phly/http

phly/http is a PHP package containing implementations of the proposed PSR HTTP message interfaces, as well as a "server" implementation similar to node's http.Server.

This package exists:

to provide a proof-of-concept of the proposed PSR HTTP message interfaces with relation to server-side applications.
to provide a node-like paradigm for PHP front controllers.
to provide a common methodology for marshaling a request from the server environment.

Installation and Requirements

Install this library using composer:

$ composer require "psr/http-message:~0.2.0@dev" "phly/http:~1.0-dev@dev"

phly/http has the following dependencies (which are managed by Composer):

psr/http-message, which defines interfaces for HTTP messages, including requests and responses. phly/http provides implementations of each of these.

Contributing

Please write unit tests for any features or bug reports you have.
Please run unit tests before opening a pull request. You can do so using ./vendor/bin/phpunit.
Please run CodeSniffer before opening a pull request, and correct any issues. Use the following to run it: ./vendor/bin/phpcs --standard=PSR2 --ignore=test/Bootstrap.php src test.

Usage

Typically, you will consume the Request and Response implementations directly in your applications.

Marshaling the request

PHP contains a plethora of information about the incoming request, and keeps that information in a variety of locations. Phly\Http\RequestFactory::fromServer() can simplify marshaling that information into a request instance.

If you do not yet have a request instance, pass it only the $_SERVER superglobal:

$request = Phly\Http\RequestFactory::fromServer($_SERVER);

If you already have a request instance, pass that as the second parameter:

// Assignment isn't necessary, as the method will write to the request you provide
$request = Phly\Http\RequestFactory::fromServer($_SERVER, $request);

Manipulating the response

Use the response object to add headers and provide content for the response.

// Write to the response body:
$response->getBody()->write("some content\n");

// Multiple calls to write() append:
$response->getBody()->write("more content\n"); // now "some content\nmore content\n"

// Add headers
// Note: headers do not need to be added before data is written to the body!
$response->setHeader('Content-Type', 'text/plain');
$response->addHeader('X-Show-Something', 'something');

"Serving" an application

Phly\Http\Server mimics a portion of the API of node's http.Server class. You can create a server in one of three ways:

// Direct instantiation, with a callback handler, request, and response
$server = new Phly\Http\Server(
    function ($request, $response, $done) {
        $response->getBody()->write("Hello world!");
    },
    $request,
    $response
);

// Using the createServer factory, and providing it $_SERVER:
$server = Phly\Http\Server::createServer(
    function ($request, $response, $done) {
        $response->getBody()->write("Hello world!");
    },
    $_SERVER
);

// Using the createServerFromRequest factory, and providing it a request:
$server = Phly\Http\Server::createServerfromRequest(
  function ($request, $response, $done) {
      $response->getBody()->write("Hello world!");
  },
  $request
);

Server callbacks can expect up to three arguments, in the following order:

$request - the request object
$response - the response object
$done - an optional callback to call when complete

Once you have your server instance, you must instruct it to listen:

$server->listen();

At this time, you can optionally provide a callback to listen(); this will be passed to the handler as the third argument ($done):

$server->listen(function ($error = null) {
    if (! $error) {
        return;
    }
    // do something with the error...
});

Typically, the listen callback will be an error handler, and can expect to receive the error as its argument.

API

Request Message

Phly\Http\Request implements Psr\Http\Message\RequestInterface, and includes the following methods:

class Request
{
    public function __construct($protocol = '1.1', $stream = 'php://input');
    public function addHeader($name, $value);
    public function addHeaders(array $headers);
    public function getBody(); // returns a Stream
    public function getHeader();
    public function getHeaderAsArray();
    public function getHeaders();
    public function getMethod();
    public function getProtocolVersion();
    public function getUrl(); // returns a Uri object
    public function removeHeader($name);
    public function setBody(Psr\Http\Message\StreamInterface $stream);
    public function setHeader($name, $value);
    public function setHeaders(array $headers);
    public function setMethod($method);
    public function setUrl($url); // string or Uri object
}

Additionally, Request implements property overloading, allowing the developer to set and retrieve arbitrary properties other than those exposed via getters. This allows the ability to pass values between handlers, if handlers implement a stack.

I recommend you store values in properties named after your handlers; use arrays or objects in cases where multiple values may be possible.

RequestFactory

This static class can be used to marshal a Request instance from the PHP environment. The primary entry point is Phly\Http\RequestFactory::fromServer(array $server, RequestInterface $request = null). This method allows you to either marshal a new request instance, or to populate an existing instance (for example, if you are using another Psr\Http\Message\RequestInterface-compatible implementation). Examples of usage are:

$request = RequestFactory::fromServer($_SERVER); // returns new Request instance

// or

$request = RequestFactory::fromServer($_SERVER, $request); // returns same request, but populated

Response Message

Phly\Http\Response implements Psr\Http\Message\ResponseInterface, and includes the following methods:

class Response
{
    public function __construct($stream = 'php://input');
    public function addHeader($name, $value);
    public function addHeaders(array $headers);
    public function getBody(); // returns a Stream
    public function getHeader();
    public function getHeaderAsArray();
    public function getHeaders();
    public function getStatusCode();
    public function getReasonPhrase();
    public function removeHeader($name);
    public function setBody(Psr\Http\Message\StreamInterface $stream);
    public function setHeader($name, $value);
    public function setHeaders(array $headers);
    public function setStatusCode($code);
    public function setReasonPhrase($phrase);
}

URI

Phly\Http\Uri models and validates URIs. The request object casts URLs to Uri objects, and returns them from getUrl(), giving an OOP interface to the parts of a URI. It implements __toString(), allowing it to be represented as a string and echo()'d directly. The following methods are pertinent:

class Uri
{
    public static function fromArray(array $parts);
    public function __construct($uri);
    public function isValid();
    public function setPath($path);
}

fromArray() expects an array of URI parts, and should contain 1 or more of the following keys:

scheme
host
port
path
query
fragment

setPath() accepts a path, but does not actually change the Uri instance; it instead returns a clone of the current instance with the new path.

The following properties are exposed for read-only access:

scheme
host
port
path
query
fragment

Stream

Phly\Http\Stream is an implementation of Psr\Http\Message\StreamableInterface, and provides a number of facilities around manipulating the composed PHP stream resource. The constructor accepts a stream, which may be either:

a stream identifier; e.g., php://input, a filename, etc.
a PHP stream resource

If a stream identifier is provided, an optional second parameter may be provided, the file mode by which to fopen the stream.

Request objects by default use a php://input stream set to read-only; Response objects by default use a php://memory with a mode of wb+, allowing binary read/write access.

In most cases, you will not interact with the Stream object directly.

Server

Phly\Http\Server represents a server capable of executing a callback. It has four methods:

class Server
{
    public function __construct(
        callable $callback,
        Psr\Http\Message\RequestInterface $request,
        Psr\Http\Message\ResponseInterface $response
    );
    public static function createServer(
        callable $callback,
        array $server // usually $_SERVER
    );
    public static function createServerFromRequest(
        callable $callback,
        Psr\Http\Message\RequestInterface $request,
        Psr\Http\Message\ResponseInterface $response = null
    );
    public function listen(callable $finalHandler = null);
}

You can create an instance of the Server using any of the constructor, createServer(), or createServerFromRequest() methods. If you wish to use the default request and response implementations, createServer($middleware, $_SERVER) is the recommended option, as this method will also marshal the Request object based on the PHP request environment. If you wish to use your own implementations, pass them to the constructor or createServerFromRequest() method (the latter will create a default Response instance if you omit it).

listen() executes the callback. If a $finalHandler is provided, it will be passed as the third argument to the $callback registered with the server.

joksnet / http