Category Archives: Lumen

PHP application in SAP Cloud Platform. With PostgreSQL, Redis and Cloud Foundry

Keeping on with my study of SAP’s cloud platform (SCP) and Cloud Foundry today I’m going to build a simple PHP application. This application serves a simple Bootstrap landing page. The application uses a HTTP basic authentication. The credentials are validated against a PostgreSQL database. It also has a API to retrieve the localtimestamp from database server (just for play with a database server). I also want to play with Redis in the cloud too, so the API request will have a Time To Live (ttl) of 5 seconds. I will use a Redis service to do it.

First we create our services in cloud foundry. I’m using the free layer of SAP cloud foundry for this example. I’m not going to explain here how to do that. It’s pretty straightforward within SAP’s coopkit. Time ago I played with IBM’s cloud foundry too. I remember that it was also very simple too.

Then we create our application (.bp-config/options.json)

{
"WEBDIR": "www",
"LIBDIR": "lib",
"PHP_VERSION": "{PHP_70_LATEST}",
"PHP_MODULES": ["cli"],
"WEB_SERVER": "nginx"
}

If we want to use our PostgreSQL and Redis services with our PHP Appliacation we need to connect those services to our application. This operation can be done also with SAP’s Cockpit.

Now is the turn of PHP application. I normally use Silex framework within my backends, but now there’s a problem: Silex is dead. I feel a little bit sad but I’m not going to cry. It’s just a tool and there’re another ones. I’ve got my example with Silex but, as an exercise, I will also do it with Lumen.

Let’s start with Silex. If you’re familiar with Silex micro framework (or another microframework, indeed) you can see that there isn’t anything especial.

use Symfony\Component\HttpKernel\Exception\HttpException;
use Symfony\Component\HttpFoundation\Request;
use Silex\Provider\TwigServiceProvider;
use Silex\Application;
use Predis\Client;

if (php_sapi_name() == "cli-server") {
    // when I start the server my local machine vendors are in a different path
    require __DIR__ . '/../vendor/autoload.php';
    // and also I mock VCAP_SERVICES env
    $env   = file_get_contents(__DIR__ . "/../conf/vcap_services.json");
    $debug = true;
} else {
    require 'vendor/autoload.php';
    $env   = $_ENV["VCAP_SERVICES"];
    $debug = false;
}

$vcapServices = json_decode($env, true);

$app = new Application(['debug' => $debug, 'ttl' => 5]);

$app->register(new TwigServiceProvider(), [
    'twig.path' => __DIR__ . '/../views',
]);

$app['db'] = function () use ($vcapServices) {
    $dbConf = $vcapServices['postgresql'][0]['credentials'];
    $dsn    = "pgsql:dbname={$dbConf['dbname']};host={$dbConf['hostname']};port={$dbConf['port']}";
    $dbh    = new PDO($dsn, $dbConf['username'], $dbConf['password']);
    $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    $dbh->setAttribute(PDO::ATTR_CASE, PDO::CASE_UPPER);
    $dbh->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);

    return $dbh;
};

$app['redis'] = function () use ($vcapServices) {
    $redisConf = $vcapServices['redis'][0]['credentials'];

    return new Client([
        'scheme'   => 'tcp',
        'host'     => $redisConf['hostname'],
        'port'     => $redisConf['port'],
        'password' => $redisConf['password'],
    ]);
};

$app->get("/", function (Application $app) {
    return $app['twig']->render('index.html.twig', [
        'user' => $app['user'],
        'ttl'  => $app['ttl'],
    ]);
});

$app->get("/timestamp", function (Application $app) {
    if (!$app['redis']->exists('timestamp')) {
        $stmt = $app['db']->prepare('SELECT localtimestamp');
        $stmt->execute();
        $app['redis']->set('timestamp', $stmt->fetch()['TIMESTAMP'], 'EX', $app['ttl']);
    }

    return $app->json($app['redis']->get('timestamp'));
});

$app->before(function (Request $request) use ($app) {
    $username = $request->server->get('PHP_AUTH_USER', false);
    $password = $request->server->get('PHP_AUTH_PW');

    $stmt = $app['db']->prepare('SELECT name, surname FROM public.user WHERE username=:USER AND pass=:PASS');
    $stmt->execute(['USER' => $username, 'PASS' => md5($password)]);
    $row = $stmt->fetch();
    if ($row !== false) {
        $app['user'] = $row;
    } else {
        header("WWW-Authenticate: Basic realm='RIS'");
        throw new HttpException(401, 'Please sign in.');
    }
}, 0);

$app->run();

Maybe the only especial thing is the way that autoloader is done. We are initializing autoloader in two different ways. One way when the application is run in the cloud and another one when the application is run locally with PHP’s built-in server. That’s because vendors are located in different paths depending on which environment the application lives in. When Cloud Foundry connect services to appliations it injects environment variables with the service configuration (credentials, host, …). It uses VCAP_SERVICES env var.

I use the built-in server to run the application locally. When I’m doing that I don’t have VCAP_SERVICES variable. And also my services information are different than when I’m running the application in the cloud. Maybe it’s better with an environment variable but I’m using this trick:

if (php_sapi_name() == "cli-server") {
    // I'm runing the application locally
} else {
    // I'm in the cloud
}

So when I’m locally I mock VCAP_SERVICES with my local values and also, for example, configure Silex application in debug mode.

Sometimes I want to run my application locally but I want to use the cloud services. I cannot connect directly to those services, but we can do it over ssh through our connected application. For example If our PostgreSQL application is running on 10.11.241.0:48825 we can map this remote port (in a private network) to our local port with this command.

cf ssh -N -T -L 48825:10.11.241.0:48825 silex

You can see more information about this command here.

Now we can use pgAdmin, for example, in our local machine to connect to cloud server.

We can do the same with Redis

cf ssh -N -T -L 54266:10.11.241.9:54266 silex

And basically that’s all. Now we’ll do the same with Lumen. The idea is create the same application with Lumen instead of Silex. It’s a dummy application but it cover task that I normally use. I also will re-use the Redis and PostgreSQL services from the previous project.

use App\Http\Middleware;
use Laravel\Lumen\Application;
use Laravel\Lumen\Routing\Router;
use Predis\Client;

if (php_sapi_name() == "cli-server") {
    require __DIR__ . '/../vendor/autoload.php';
    $env = 'dev';
} else {
    require 'vendor/autoload.php';
    $env = 'prod';
}

(new Dotenv\Dotenv(__DIR__ . "/../env/{$env}"))->load();

$app = new Application();

$app->routeMiddleware([
    'auth' => Middleware\AuthMiddleware::class,
]);

$app->register(App\Providers\VcapServiceProvider::class);
$app->register(App\Providers\StdoutLogServiceProvider::class);
$app->register(App\Providers\DbServiceProvider::class);
$app->register(App\Providers\RedisServiceProvider::class);

$app->router->group(['middleware' => 'auth'], function (Router $router) {
    $router->get("/", function () {
        return view("index", [
            'user' => config("user"),
            'ttl'  => getenv('TTL'),
        ]);
    });

    $router->get("/timestamp", function (Client $redis, PDO $conn) {
        if (!$redis->exists('timestamp')) {
            $stmt = $conn->prepare('SELECT localtimestamp');
            $stmt->execute();
            $redis->set('timestamp', $stmt->fetch()['TIMESTAMP'], 'EX', getenv('TTL'));
        }

        return response()->json($redis->get('timestamp'));
    });
});

$app->run();

I’ve created four servicer providers. One for handle Database connections (I don’t like ORMs)

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use PDO;

class DbServiceProvider extends ServiceProvider
{
    public function register()
    {
    }

    public function boot()
    {
        $vcapServices = app('vcap_services');

        $dbConf = $vcapServices['postgresql'][0]['credentials'];
        $dsn    = "pgsql:dbname={$dbConf['dbname']};host={$dbConf['hostname']};port={$dbConf['port']}";
        $dbh    = new PDO($dsn, $dbConf['username'], $dbConf['password']);
        $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        $dbh->setAttribute(PDO::ATTR_CASE, PDO::CASE_UPPER);
        $dbh->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);

        $this->app->bind(PDO::class, function ($app) use ($dbh) {
            return $dbh;
        });
    }
}

Another one for Redis. I need to study a little bit more Lumen. I know that Lumen has a built-in tool to work with Redis.

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use Predis\Client;

class RedisServiceProvider extends ServiceProvider
{
    public function register()
    {
    }

    public function boot()
    {
        $vcapServices = app('vcap_services');
        $redisConf    = $vcapServices['redis'][0]['credentials'];

        $redis = new Client([
            'scheme'   => 'tcp',
            'host'     => $redisConf['hostname'],
            'port'     => $redisConf['port'],
            'password' => $redisConf['password'],
        ]);

        $this->app->bind(Client::class, function ($app) use ($redis) {
            return $redis;
        });
    }
}

Another one to tell monolog to send logs to Stdout

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use Monolog;

class StdoutLogServiceProvider extends ServiceProvider
{
    public function register()
    {
        app()->configureMonologUsing(function (Monolog\Logger $monolog) {
            return $monolog->pushHandler(new \Monolog\Handler\ErrorLogHandler());
        });
    }
}

And the last one to work with Vcap environment variables. Probably I need to integrate it with dotenv files

namespace App\Providers;

use Illuminate\Support\ServiceProvider;

class VcapServiceProvider extends ServiceProvider
{
    public function register()
    {
        if (php_sapi_name() == "cli-server") {
            $env = file_get_contents(__DIR__ . "/../../conf/vcap_services.json");
        } else {
            $env = $_ENV["VCAP_SERVICES"];
        }

        $vcapServices = json_decode($env, true);

        $this->app->bind('vcap_services', function ($app) use ($vcapServices) {
            return $vcapServices;
        });
    }
}

We also need to handle authentication (http basic auth in this case) so we’ll create a simple middleware

namespace App\Http\Middleware;

use Closure;
use Illuminate\Http\Request;
use PDO;

class AuthMiddleware
{
    public function handle(Request $request, Closure $next)
    {
        $user = $request->getUser();
        $pass = $request->getPassword();

        $db = app(PDO::class);
        $stmt = $db->prepare('SELECT name, surname FROM public.user WHERE username=:USER AND pass=:PASS');
        $stmt->execute(['USER' => $user, 'PASS' => md5($pass)]);
        $row = $stmt->fetch();
        if ($row !== false) {
            config(['user' => $row]);
        } else {
            $headers = ['WWW-Authenticate' => 'Basic'];
            return response('Admin Login', 401, $headers);
        }

        return $next($request);
    }
}

In summary: Lumen is cool. The interface is very similar to Silex. I can swap my mind from thinking in Silex to thinking in Lumen easily. Blade instead Twig: no problem. Service providers are very similar. Routing is almost the same and Middlewares are much better. Nowadays backend is a commodity for me so I don’t want to spend to much time working on it. I want something that just work. Lumen looks like that.

Both projects: Silex and Lumen are available in my github

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Taking photos with an ionic2 application and upload them to S3 Bucket with SAP’s Cloud Foundry using Silex and Lumen

Today I want to play with an experiment. When I work with mobile applications, I normally use ionic and on-premise backends. Today I want play with cloud based backends. In this small experiment I want to use an ionic2 application to take pictures and upload them to an S3 bucket. Let’s start.

First I’ve created a simple ionic2 application. It’s a very simple application. Only one page with a button to trigger the device’s camera.

<ion-header>
    <ion-navbar>
        <ion-title>
            Photo
        </ion-title>
    </ion-navbar>
</ion-header>

<ion-content padding>
    <ion-fab bottom right>
        <button ion-fab (click)="takePicture()">
            <ion-icon  name="camera"></ion-icon>
        </button>
    </ion-fab>
</ion-content>

The controller uses @ionic-native/camera to take photos and later we use @ionic-native/transfer to upload them to the backend.

import {Component} from '@angular/core';
import {Camera, CameraOptions} from '@ionic-native/camera';
import {Transfer, FileUploadOptions, TransferObject} from '@ionic-native/transfer';
import {ToastController} from 'ionic-angular';
import {LoadingController} from 'ionic-angular';

@Component({
    selector: 'page-home',
    templateUrl: 'home.html'
})
export class HomePage {
    constructor(private transfer: Transfer,
                private camera: Camera,
                public toastCtrl: ToastController,
                public loading: LoadingController) {
    }

    takePicture() {
        const options: CameraOptions = {
            quality: 100,
            destinationType: this.camera.DestinationType.FILE_URI,
            sourceType: this.camera.PictureSourceType.CAMERA,
            encodingType: this.camera.EncodingType.JPEG,
            targetWidth: 1000,
            targetHeight: 1000,
            saveToPhotoAlbum: false,
            correctOrientation: true
        };

        this.camera.getPicture(options).then((uri) => {
            const fileTransfer: TransferObject = this.transfer.create();

            let options: FileUploadOptions = {
                fileKey: 'file',
                fileName: uri.substr(uri.lastIndexOf('/') + 1),
                chunkedMode: true,
                headers: {
                    Connection: "close"
                },
                params: {
                    metadata: {foo: 'bar'},
                    token: 'mySuperSecretToken'
                }
            };

            let loader = this.loading.create({
                content: 'Uploading ...',
            });

            loader.present().then(() => {
                let s3UploadUri = 'https://myApp.cfapps.eu10.hana.ondemand.com/upload';
                fileTransfer.upload(uri, s3UploadUri, options).then((data) => {
                    let message;
                    let response = JSON.parse(data.response);
                    if (response['status']) {
                        message = 'Picture uploaded to S3: ' + response['key']
                    } else {
                        message = 'Error Uploading to S3: ' + response['error']
                    }
                    loader.dismiss();
                    let toast = this.toastCtrl.create({
                        message: message,
                        duration: 3000
                    });
                    toast.present();
                }, (err) => {
                    loader.dismiss();
                    let toast = this.toastCtrl.create({
                        message: "Error",
                        duration: 3000
                    });
                    toast.present();
                });
            });
        });
    }
}

Now let’s work with the backend. Next time I’ll use JavaScript AWS SDK to upload pictures directly from mobile application (without backend), but today We’ll use a backend. Nowadays I’m involved with SAP Cloud platform projects, so we’ll use SAP’s Cloud Foundry tenant (using a free account). In this tenant we’ll create a PHP application using the PHP buildpack with nginx

applications:
– name: myApp
path: .
memory: 128MB
buildpack: php_buildpack

The PHP application is a simple Silex application to handle the file uploads and post the pictures to S3 using the official AWS SDK for PHP (based on Guzzle)

use Symfony\Component\HttpFoundation\Request;
use Silex\Application;
use Aws\S3\S3Client;

require 'vendor/autoload.php';

$app = new Application([
    'debug'        => false,
    'aws.config'   => [
        'debug'       => false,
        'version'     => 'latest',
        'region'      => 'eu-west-1',
        'credentials' => [
            'key'    => $_ENV['s3key'],
            'secret' => $_ENV['s3secret'],
        ],
    ],
]);

$app['aws'] = function () use ($app) {
    return new S3Client($app['aws.config']);
};

$app->post('/upload', function (Request $request, Application $app) {
    $metadata = json_decode($request->get('metadata'), true);
    $token    = $request->get('token');

    if ($token === $_ENV['token']) {
        $fileName = $_FILES['file']['name'];
        $fileType = $_FILES['file']['type'];
        $tmpName  = $_FILES['file']['tmp_name'];

        /** @var \Aws\S3\S3Client $s3 */
        $s3 = $app['aws'];
        try {
            $key = date('YmdHis') . "_" . $fileName;
            $s3->putObject([
                'Bucket'      => $_ENV['s3bucket'],
                'Key'         => $key,
                'SourceFile'  => $tmpName,
                'ContentType' => $fileType,
                'Metadata'    => $metadata,
            ]);
            unlink($tmpName);

            return $app->json([
                'status' => true,
                'key'    => $key,
            ]);
        } catch (Aws\S3\Exception\S3Exception $e) {
            return $app->json([
                'status' => false,
                'error'  => $e->getMessage(),
            ]);
        }
    } else {
        return $app->json([
            'status' => false,
            'error'  => "Token error",
        ]);
    }
});

$app->run();

I just wanted a simple prototype (a working one). Enough for a Sunday morning hacking.

UPDATE

I had this post ready weeks ago but something has changed. Silex is dead. So, as an exercise I’ll migrate current Silex application to Lumen (a quick prototype).

That’s the main application.

use App\Http\Middleware;
use Aws\S3\S3Client;
use Illuminate\Http\Request;
use Laravel\Lumen\Application;

require 'vendor/autoload.php';

(new Dotenv\Dotenv(__DIR__ . "/../env"))->load();

$app = new Application();

$app->routeMiddleware([
    'auth' => Middleware\AuthMiddleware::class,
]);

$app->register(App\Providers\S3ServiceProvider::class);

$app->group(['middleware' => 'auth'], function (Application $app) {
    $app->post('/upload', function (Request $request, Application $app, S3Client $s3) {
        $metadata = json_decode($request->get('metadata'), true);
        $fileName = $_FILES['file']['name'];
        $fileType = $_FILES['file']['type'];
        $tmpName  = $_FILES['file']['tmp_name'];

        try {
            $key = date('YmdHis') . "_" . $fileName;
            $s3->putObject([
                'Bucket'      => getenv('s3bucket'),
                'Key'         => $key,
                'SourceFile'  => $tmpName,
                'ContentType' => $fileType,
                'Metadata'    => $metadata,
            ]);
            unlink($tmpName);

            return response()->json([
                'status' => true,
                'key'    => $key,
            ]);
        } catch (Aws\S3\Exception\S3Exception $e) {
            return response()->json([
                'status' => false,
                'error'  => $e->getMessage(),
            ]);
        }
    });
});

$app->run();

Probably we can find a S3 Service provider, but I’ve built a simple one for this example.

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use Aws\S3\S3Client;

class S3ServiceProvider extends ServiceProvider
{
    public function register()
    {
        $this->app->bind(S3Client::class, function ($app) {
            $conf = [
                'debug'       => false,
                'version'     => getenv('AWS_VERSION'),
                'region'      => getenv('AWS_REGION'),
                'credentials' => [
                    'key'    => getenv('s3key'),
                    'secret' => getenv('s3secret'),
                ],
            ];

            return new S3Client($conf);
        });
    }
}

And also I’m using a middleware for the authentication

namespace App\Http\Middleware;

use Closure;
use Illuminate\Http\Request;

class AuthMiddleware
{
    public function handle(Request $request, Closure $next)
    {
        $token = $request->get('token');
        if ($token === getenv('token')) {
            return response('Admin Login', 401);
        }

        return $next($request);
    }
}

Ok. I’ll post this article soon. At least before Lumen will be dead also, and I need to update this post again 🙂

Full project (mobile application and both backends) in my githubgithub

Silex is dead (… or not)

The last week was deSymfony conference in Castellón (Spain). IMHO deSymfony is the best conference I’ve ever attended. The talks are good but from time to now I appreciate this kind of events not because of them. I like to go to events because of people, the coffee breaks and the community (and in deSymfony is brilliant at this point). This year I cannot join to the conference. It was a pity. A lot of good friends there. So I only can follow the buzz in Twitter, read the published slides (thanks Raul) and wait for the talk videos in youtube.

In my Twitter timeline especially two tweets get my attention. One tweet was from Julieta Cuadrado and another one from Asier Marqués.

Tweets are in Spanish but the translation is clear: Javier Eguiluz (Symfony Core Team member and co-organizer of the conference) said in his talk: “Silex is dead”. At the time I read the tweets his slides were not available yet, but a couple of days after the slides were online. The slide 175 is clear “Silex is dead”

Javier recommends us not to use Silex in future new projects and mark existing ones as “legacy”. It’s hard to me. If you have ever read my blog you will notice that I’m a big fan of Silex. Each time I need a backend, a API/REST server of something like that the first thing I do is “composer require silex/silex”. I know that Silex has limitations. It’s built on top of Pimple dependency injection container and Pimple is really awful, but this microframework gives to me exactly what I need. It’s small, simple, fast enough and really easy to adapt to my needs.

I remember a dinner in deSymfony years ago speaking with Javier in Barcelona. He was trying to “convince” me to use Symfony full stack framework instead of Silex. He almost succeeded, but I didn’t like Symfony full stack. Too complicated for me. A lot interesting things but a lot of them I don’t really need. I don’t like Symfony full stack framework, but I love Symfony. For me it’s great because of its components. They’re independent pieces of code that I can use to fit exactly to my needs instead of using a full-stack framework. I’ve learn a lot SOLID reading and hacking with Symfony components. I’m not saying that full stack frameworks are bad. I only say that they’re not for me. If I’m forced to use them I will do it, but if I can choose, I definitely choose a micro framework, even for medium an big projects.

New version of Symfony (Symfony 4) is coming next November and reading the slides of Javier at slideshare I can get an idea of its roadmap. My summary is clear: “Brilliant”. It looks like the people of Symfony listen to my needs and change all the framework to adapt it to me. After understand the roadmap I think that I need to change to title of the post (Initially it was only “Silex is dead”). Silex is not dead. For me Symfony (the full stack framework) is the death. Silex will be upgraded and will be renamed to Symfony (I know that this assertion is subjective. It’s just my point of view). So the bad feeling that I felt when I read Julieta and Asier’s tweets turns into a good one. Good move SensioLabs!

But I’ve got a problem right now. What can I do if I need to start a new project today? Symfony 4 isn’t ready yet. Javier said that we can use Symfony Flex and create new projects with Symfony 3 with the look and feel of Symfony 4, but Flex is still in alpha and I don’t want to play with alpha tools in production. Especially in the backend. I’m getting older, I know. For me the backend is a commodity right now. I need the backend to serve JSON mainly.

I normally use PHP and Silex here only because I’m very confortable with it. In the projects, business people doesn’t care about technologies and frameworks. It’s our job (or our problem depending on how to read it). And don’t forget one thing: Developers are part of business, so in one part of my mind I don’t care about frameworks also. I care about making things done, maximising the potential of technology and driving innovation to customer benefits (good lapidary phrase, isn’t it?).

So I’ve started looking for alternatives. My objective here is clear: I want to find a framework to do the things that I usually do with Silex. Nothing more. And there’s something important here: The tool must be easy to learn. I want to master (or at least become productive) the tool in a couple of days maximum.

I started with the first one: Lumen and I think I will stop searching. Lumen is the micro framework of Laravel. Probably in the PHP world now there’re two major communities: Symfony and Laravel. Maybe if we’re strict Laravel and Symfony are not different communities. In fact Laravel and Symfony shares a lot of components. So maybe both communities are the same.

I’ve almost never played with Laravel and it’s time to study it a little bit. Time ago I used Eloquent ORM but since I hate ORMs I always return to PDO/DBAL. As I said before I didn’t like Symfony full stack framework. It’s too complex for me, and Laravel is the same. When I started with PHP (in the early 2000) there weren’t any framework. I remember me reading books of Java and J2EE. Trying to understand something in its nightmare of acronyms, XMLs configurations and trying to build my own framework in PHP. Now in 2017 to build our own framework in PHP is good learning point but use it with real projects is ridiculous. As someone said before (I don’t remember who) “Everybody must build his own framework, and never use it at all“.

Swap from Silex to Lumen is pretty straightforward. In fact with one ultra-minimal application it’s exactly the same:

use Silex\Application;

$app = new Application();

$app->get("/", function() {
    return "Hello from Silex";
});

$app->run();
use Laravel\Lumen\Application;

$app = new Application();

$app->get("/", function() {
    return "Hello from Lumen";
});

$app->run();

If you’re a Silex user you only need a couple of hours reading the Lumen docs and you will be able to set up a new project without any problem. Concepts are the same, slight differences and even cool things such as groups and middlewares. Nothing impossible to do with Silex, indeed, but with a very smart and simple interface. If I need to create a new project right now I will use Lumen without any doubt.

Next winter, when Symfony 4 arrives, I probably will face the problem of choose. But past years I’ve been involved into the crazy world of JavaScript: Angular, Angular2, React, npm, yarn, webpack, … If I’ve survived this (finally I choose JQuery, but that’s a different story :), I am ready for all right now.