Added a readme page for quick info and demo

README.md

@@ -0,0 +1,92 @@
+Object-oriented implementation of FCGI Protocol for PHP
+---------------------------
+
+FastCGI is an open extension to CGI that provides high performance for all Internet applications without the penalties
+of Web server APIs.
+
+Many modern web-servers such as nginx, apache, lighthttpd, etc are communicating with PHP via FCGI. So, this protocol
+is well known and used in many applications. More detailed information about the protocol is available here here:
+http://www.fastcgi.com/devkit/doc/fcgi-spec.html
+
+Usage
+------------
+This library can be used for implementing both client and server side of FCGI application. For example, nginx can
+connect to the PHP FCGI daemon, or some library code can connect to the FPM as a FCGI client.
+
+To install this library, just write
+
+``` bash
+$ composer require lisachenko/protocol-fcgi
+```
+
+After that you can use an API to parse/create FCGI requests and responses.
+
+Simple FCGI-client:
+```php
+<?php
+
+use Protocol\FCGI;
+use Protocol\FCGI\FrameParser;
+use Protocol\FCGI\Record;
+use Protocol\FCGI\Record\BeginRequest;
+use Protocol\FCGI\Record\Params;
+use Protocol\FCGI\Record\Stdin;
+
+include "vendor/autoload.php";
+
+// Let's connect to the local php-fpm daemon directly
+$phpSocket = fsockopen('127.0.0.1', 9001, $errorNumber, $errorString);
+$packet    = '';
+
+// Prepare our sequence for querying PHP file
+$packet .= new BeginRequest(FCGI::RESPONDER);;
+$packet .= new Params(['SCRIPT_FILENAME' => '/var/www/some_file.php']);
+$packet .= new Params();
+$packet .= new Stdin();
+
+fwrite($phpSocket, $packet);
+
+$response = '';
+while ($partialData = fread($phpSocket, 4096)) {
+    $response .= $partialData;
+    while (FrameParser::hasFrame($response)) {
+        $record = FrameParser::parseFrame($response);
+        var_dump($record);
+    };
+};
+
+fclose($phpSocket);
+```
+
+To implement FCGI server, just create a socket and make request-response loop
+
+```php
+
+use Protocol\FCGI;
+use Protocol\FCGI\FrameParser;
+use Protocol\FCGI\Record;
+use Protocol\FCGI\Record\BeginRequest;
+use Protocol\FCGI\Record\Params;
+use Protocol\FCGI\Record\Stdin;
+
+include "vendor/autoload.php";
+
+$server = stream_socket_server("tcp://127.0.0.1:9001" , $errorNumber, $errorString);
+
+// Just take the first one request and process it
+$phpSocket = stream_socket_accept($server);
+
+$response = '';
+while ($partialData = fread($phpSocket, 4096)) {
+    $response .= $partialData;
+    while (FrameParser::hasFrame($response)) {
+        $record = FrameParser::parseFrame($response);
+        var_dump($record);
+    };
+};
+
+// We don't respond correctly here, it's a task for your application
+
+fclose($phpSocket);
+fclose($server);
+```