Add docs and a hello world example

docs/http/psrs-middlewares-pipelines.md

@@ -1,2 +1,86 @@
 # PSR-7, PSR-15, Middlewares & Pipelines
 
+Siler embraces community standards and tools. For HTTP abstraction, the PHP Framework Interop Group recommends HTTP message interfaces (PSR-7) and HTTP Server Request Handlers (PSR-15).
+
+This interfaces are already (and amazingly) implemented by Zend, in the projects: Diactoros and Stratigility. Siler wrapps them and exposes a function-friendy API handling state internally while achiving a fully-featured and declarative way to: **Pipeline Middlewares**.
+
+## Usage
+
+### Hello World
+
+A very simple example:
+
+```php
+use function Siler\Diactoros\request;
+use function Siler\Diactoros\text;
+use function Siler\HttpHandlerRunner\sapi_emit;
+use function Siler\Stratigility\handle;
+use function Siler\Stratigility\pipe;
+
+pipe(function ($request, $handler) {
+    return text('hello world');
+});
+
+sapi_emit(handle(request()));
+```
+
+It's more `use`s than actual code because Siler is abstracting all the way down for you.
+
+| API | Description |
+| --- | --- |
+| `pipe` | Creates a Stratigility `MiddlewarePipe` with a default name and pipes the given Clousure to it already wrapping it inside a `MiddlewareInterface` decorator, or you can pass any implementation `MiddlewareInterface` to it. |
+| `text` | Creates a Diactoros `TextResponse`. The Diactoros namespace in Siler is basically just helper functions for Responses. |
+| `sapi_emit` | Creates and immediatly calls `emit` method on a HttpHandlerRunner `SapiEmitter`.
+| `handle` | Calls `handle` on a `MiddlewarePipe` marshaling the Request. | 
+| `request` | Creates a Diactoros `ServerRequest` using PHP's Globals. |
+
+### Siler's Routes
+
+You can also run pipelines for specific routes:
+
+```php
+use Siler\Diactoros;
+use Siler\Http\Request;
+use Siler\HttpHandlerRunner;
+use Siler\Route;
+use Siler\Stratigility;
+
+$userMiddleware = function ($request, $handler) {
+    $token = Request\get('token');
+
+    if (empty($token)) {
+        return Diactoros\json('no user', 401);
+    }
+
+    $user = "get_user_by_token:$token";
+    $request = $request->withAttribute('user', $user);
+
+    return $handler->handle($request);
+};
+
+$homeHandler = function () {
+    return Diactoros\json('welcome');
+};
+
+$adminHandler = function ($request) {
+    return Diactoros\json(['user' => $request->getAttribute('user')]);
+};
+
+$secretHandler = function ($request) {
+    return Diactoros\json(['user' => $request->getAttribute('user')]);
+};
+
+Stratigility\pipe($userMiddleware, 'auth');
+
+$request = Diactoros\request();
+$response = Route\match([
+    Route\get('/', $homeHandler, $request),
+    Route\get('/admin', Stratigility\process($request, 'auth')($adminHandler), $request),
+    Route\get('/secret', Stratigility\process($request, 'auth')($secretHandler), $request),
+    Diactoros\json('not found', 404),
+]);
+
+HttpHandlerRunner\sapi_emit($response);
+```
+
+The second argument on `pipe` here is a Pipeline name, you can pipe middlewares to any number of pipelines, then in `Stratigility\process` we marshal it, from the given `$request` and returns a Clousure to be called on a final handler.

examples/zend-party/hello-world/index.php

@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+require_once __DIR__.'/../../../vendor/autoload.php';
+
+use function Siler\Diactoros\request;
+use function Siler\Diactoros\text;
+use function Siler\HttpHandlerRunner\sapi_emit;
+use function Siler\Stratigility\handle;
+use function Siler\Stratigility\pipe;
+
+pipe(function ($request, $handler) {
+    return text('hello world');
+});
+
+sapi_emit(handle(request()));