SOA Middleware

Not today's topic

Node.JS Middleware

var express = require('express')
var app = express()

app.get('/', function (req, res) {
    res.send('Hello World!')
})

app.listen(3000)

Who uses?

Zend Expressive

• easy to use micro-framework
• PSR-15, PSR-11, PSR-7 compliant
• supports middleware
• component based

http://phpmiddleware.websc

using Postman

postman --disable-gpu

Default Installation

cd /var/www/html/summercamp/

composer create-project zendframework/zend-expressive-skeleton phpmiddleware

Filesystem layout

Let's open PHPStorm at:

/var/www/html/summercamp/phpmiddleware

├── bin
├── config
├── data
├── docs
├── public
│     └── index.php
├── src
├── test
└── vendor

Apache's configuration

/etc/apache2/sites-available/phpmiddleware.conf

Document root

/var/www/html/summercamp/phpmiddleware/public

public/index.php

chdir(dirname(__DIR__));
require 'vendor/autoload.php';

call_user_func(function () {
    /** @var \Interop\Container\ContainerInterface $container */
    $container = require 'config/container.php';

    /** @var \Zend\Expressive\Application $app */
    $app = $container->get(\Zend\Expressive\Application::class);

    require 'config/pipeline.php';
    require 'config/routes.php';

    $app->run();
});

config/config.php

$aggregator = new ConfigAggregator([
    App\ConfigProvider::class,
    new PhpFileProvider('config/autoload/{{,*.}global,{,*.}local}.php'),
    new PhpFileProvider('config/development.config.php')
]);

return $aggregator->getMergedConfig();

config/pipeline.php

$app->pipe(ErrorHandler::class);

$app->pipeRoutingMiddleware();

$app->pipeDispatchMiddleware();

$app->pipe(NotFoundHandler::class);

config/routes.php

$app->get('/', App\Action\HomePageAction::class, 'home');
$app->get('/api/ping', App\Action\PingAction::class, 'api.ping');

config/routes.php

$app->get('/', App\Action\HomePageAction::class, 'home');
$app->get('/api/ping', App\Action\PingAction::class, 'api.ping');

config/routes.php

$app->get('/', App\Action\HomePageAction::class, 'home');
$app->get('/api/ping', App\Action\PingAction::class, 'api.ping');

src/App/Action/PingAction.php

namespace App\Action;

class PingAction implements ServerMiddlewareInterface
{
    public function process(
        ServerRequestInterface $request,
        DelegateInterface $delegate
    ) {
        return new JsonResponse(['ack' => time()]);
    }
}

PSR-7 interfaces

PSR-7 interfaces

PSR-7 MessageInterface

namespace Psr\Http\Message;

interface MessageInterface
{
    public function getProtocolVersion();
    public function withProtocolVersion($version);
    public function getHeaders();
    public function hasHeader($name);
    public function getHeader($name);
    public function getHeaderLine($name);
    public function withHeader($name, $value);
    public function withAddedHeader($name, $value);
    public function withoutHeader($name);
    public function getBody();
    public function withBody(StreamInterface $body);
}

PSR-7 RequestInterface

namespace Psr\Http\Message;

interface RequestInterface extends MessageInterface
{
    public function getRequestTarget();
    public function withRequestTarget($requestTarget);
    public function getMethod();
    public function withMethod($method);
    public function getUri();
    public function withUri(UriInterface $uri, $preserveHost = false);
}

PSR-7 ServerRequestInterface

namespace Psr\Http\Message;

interface ServerRequestInterface extends RequestInterface
{
    public function getServerParams();
    public function getCookieParams();
    public function withCookieParams(array $cookies);
    public function getQueryParams();
    public function withQueryParams(array $query);
    public function getUploadedFiles();
    public function withUploadedFiles(array $uploadedFiles);
    public function getParsedBody();
    public function withParsedBody($data);
    public function getAttributes();
    public function getAttribute($name, $default = null);
    public function withAttribute($name, $value);
    public function withoutAttribute($name);
}

PSR-7 ResponseInterface

namespace Psr\Http\Message;

interface ResponseInterface extends MessageInterface
{
    public function getStatusCode();
    public function withStatus($code, $reasonPhrase = '');
    public function getReasonPhrase();
}

Interacting with PSR-7 messages

$response->setStatusCode(418);

$response = $response->withStatusCode(418);

Time to do stuff...

git checkout 03-welcome

Exercise 1 Solution

config/routes.php

$app->get('/', \App\Action\IndexAction::class, 'index');

$app->get('/hello', \App\Action\HelloAction::class, 'hello');

Check it out with

git checkout 04-hello-name

Let's move on...

git checkout 06-chocolates-route

config/routes.php

$app->get('/', \App\Action\IndexAction::class, 'index');

$app->get('/hello', \App\Action\HelloAction::class, 'hello');

$app->get('/chocolates', \App\Action\ChocolatesAction::class, 'chocolates');

src/App/Action/ChocolatesAction.php

final class ChocolatesAction implements MiddlewareInterface
{
    /**
     * @var ChocolatesServiceInterface
     */
    private $chocolates;

    public function __construct(ChocolatesServiceInterface $chocolates)
    {
        $this->chocolates = $chocolates;
    }

    public function process(
        ServerRequestInterface $request,
        DelegateInterface $delegate
    ): ResponseInterface
    {
        return new JsonResponse($this->chocolates->getAll());
    }
}

config/config.php

$aggregator = new ConfigAggregator([
    App\ConfigProvider::class,
    new PhpFileProvider('config/autoload/{{,*.}global,{,*.}local}.php'),
    new PhpFileProvider('config/development.config.php')
]);

return $aggregator->getMergedConfig();

src/App/ConfigProvider.php

public function getDependencies()
{
    return [
        'factories'  => [
            // ACTIONS
            ChocolatesAction::class => ChocolatesActionFactory::class,

            // SERVICES
            ChocolatesServiceInterface::class => ChocolatesServiceFactory::class,

            // REPOSITORIES
            Chocolates::class => SqlChocolatesFactory::class,
        ],
    ];
}

PSR-11 ContainerInterface

interface ContainerInterface
{
    /**
     * @param string $id Identifier of the entry to look for.
     *
     * @throws NotFoundExceptionInterface No entry was found for the identifier.
     * @throws ContainerExceptionInterface Error while retrieving the entry.
     *
     * @return mixed Entry.
     */
    public function get($id);

    /**
     * @param string $id Identifier of the entry to look for.
     *
     * @return bool
     */
    public function has($id);
}

Exercise 2 Solution

final class ChocolateDetailsAction implements MiddlewareInterface
{
    public function process(
        ServerRequestInterface $request,
        DelegateInterface $delegate
    ): ResponseInterface
    {
        $chocolateId = ChocolateId::fromString($request->getAttribute('id'));

        $chocolate = $this->chocolatesService->getChocolate($chocolateId);

        return new JsonResponse($chocolate);
    }
}

You can check them out with

git checkout 07-chocolate-details-route

git checkout 08-users

But hey, did you notice?

class ...Action implements MiddlewareInterface
{
    public function process(
        ServerRequestInterface $request,
        DelegateInterface $delegate
    ): ResponseInterface
    {
        ...
    }
}

Middleware

Back to code...

git checkout 10-access-log

config/pipeline.php

$app->pipe(ErrorHandler::class);

$app->pipe(new \Middlewares\ClientIp());
$app->pipe(\Middlewares\AccessLog::class);

$app->pipeRoutingMiddleware();

$app->pipeDispatchMiddleware();

$app->pipe(NotFoundHandler::class);

config/autoload/dependencies.global.php

return [
    'dependencies' => [
        'factories'  => [
            \Middlewares\AccessLog::class =>
                \App\Container\Middleware\AccessLogFactory::class,
        ],
    ],
];

How about other actions?

git checkout 15-delete-chocolate

Related Actions

App\Action\SubmitChocolateAction.php

App\Action\ApproveChocolateAction.php

App\Action\DeleteChocolateAction.php

What about authentication?

git checkout 16.1-basic-http-authentication

Let's switch to JWT...

git checkout 17.3-jwt-authentication

JWT

config/routes.php

$app->post('/token', \App\Action\TokenAction::class, 'token');

Solution to exercise(s) 4

git checkout 17.3-jwt-authentication

git checkout 18-authorization

config/routes.php

$app->post(
    '/submit',
    [
        \Middlewares\HttpAuthentication::class,
        \App\Action\SubmitChocolateAction::class,
    ],
    'submit'
);

$app->post(
    '/approve/{id}',
    [
        \Middlewares\HttpAuthentication::class,
        \App\Middleware\Authorization::class,
        \App\Action\ApproveChocolateAction::class,
    ],
    'approve'
);

Exercise 5 (bonus)

Get to branch 19-phpunit or 20-behat

let's write a test for the Authorization Middleware of the last exercise

docs/readme.html

Solution to exercise 5

git checkout 19.1-phpunit
                    

git checkout 20.1-behat
                    

Slim

Slim

$app->add(new AccessLog($logger));

$app->add(new ClientIp());

$app->add(new BasicAuthentication($users));

Other middleware dispatchers

• Telegraphp
• Middleman
• Ellipsephp dispatcher

Middleman

$dispatcher = new Dispatcher([
    new BasicAuthentication($users),
    new ClientIp(),
    new AccessLog($logger)
]);

Speakers love feedback

Leave your feedback at https://joind.in/talk/668cc

Marco @marcoshuttle m.perone@mvlabs.it

Steve @maraspin s.maraspin@mvlabs.it