Cristian Vasta

Cristian Vasta

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Server health monitoring for Laravel apps | Learning Laravel

There are lots of server monitoring solutions out there. Most popular among them are Datadog and New Relic. Some server infrastructure providers such as DigitalOcean also comes with basic server monitoring features such as disk, CPU, and memory. There are also open-source solutions such as Nagios. But more often than not, especially on small projects, a lot of the functionality that these services offer is more than what you need. Aside from that, they’re usually not cheap.

If you’re like me and all you want is some basic functionality such as realtime monitoring of whether specific software on your server is running or not, then creating your own server monitoring app is the way to go.

In this tutorial, we’ll be creating a live server monitoring app with Laravel and Pusher Channels.

Prerequisites

Knowledge of PHP is required to follow this tutorial. You also need to know basic server management for infrastructure providers like DigitalOcean or Linode. Things like generating ssh keys and adding them to your remote server.

Development environment You need to have Apache, PHP, Composer, MySQL, and Node installed on your machine. The easiest way to follow this tutorial if you don’t already have the development environment is to use either Laravel Homestead or Laravel Valet. If you have a bit more time, you can install Laradock instead. This is the same environment that I’ve used for creating this tutorial.

Out of the box, Laravel Homestead and Laradock will come pre-installed with the required software.

If you opt for Laravel Valet, you also need to install PHP, Composer, MySQL, and Node separately. For the HTTP server, it’s going to use PHP’s built-in server instead of Apache. Just follow their documentation for the instructions.

A remote server to be monitored is also required. Don’t assign a password to the ssh key you generate as the tool that we will be using for logging in remotely to the server doesn’t support logging in with ssh keys that require a password. This tutorial won’t be covering how to add ssh keys to a remote server. But if you’re using a Linux-based server, all you have to do is log in to it and append your local machine’s public ssh key to the ~/.ssh/authorized_keys file in the server.

Lastly, you need to have a Pusher account with an app instance which you can use for testing.

Package versions The following package versions are used for the app:

  • laravel/framework 5.8
  • pusher/pusher-php-server 4.0
  • spatie/laravel-server-monitor 1.0

You don’t have to use the same versions, but it’s good to know if you encounter any compatibility issues.

App overview

We’ll be building a live server monitor that will constantly check for various server status such as disk space, CPU, and memory. It will also check if the software you’re using to run your server is running or not. The data on the page will automatically be updated at a specific interval.

Here’s what the app will look like:

You can view the code on its GitHub repo.

Bootstrapping the app

Let’s get started by creating a new Laravel project:

    composer create-project --prefer-dist laravel/laravel liveservermonitor

This will create a new liveservermonitor folder on your working directory. Navigate inside that and it will serve as the root directory for this project.

Create and add the database config Log in to the MySQL server and create the database that we will be using to store the status of the servers to be monitored:

    mysql -u root -p
    CREATE DATABASE server_monitor;

Next, open the .env file and set your database credentials. Replace the values for the one’s which starts with YOUR_:

    DB_CONNECTION=mysql
    DB_HOST=YOUR_DB_HOST
    DB_PORT=3306
    DB_DATABASE=server_monitor
    DB_USERNAME=YOUR_DB_USERNAME
    DB_PASSWORD=YOUR_DB_PASSWORD

Install the backend dependencies Next, we need to install the libraries we need:

    composer require spatie/laravel-server-monitor pusher/pusher-php-server

Here’s a breakdown of what each one does:

Once the libraries are installed, we need to register the service provider for the laravel-server-monitor package. Open the config/app.php file and add the following under the providers array. While you’re there, uncomment the Broadcast service provider as well. This will let us use the event broadcasting feature in Laravel. We use it to broadcast the event for when laravel-server-monitor has finished checking the server status:

    'providers' => [
      // ...
      App\Providers\BroadcastServiceProvider::class, // uncomment this
      Spatie\ServerMonitor\ServerMonitorServiceProvider::class, // add this
    ];

Next, generate the migration files for creating the tables to be used by laravel-server-monitor then run the migrations:

    php artisan vendor:publish --provider="Spatie\ServerMonitor\ServerMonitorServiceProvider" --tag="migrations"
    php artisan migrate

This will create the hosts table:

And the checks table:

The hosts table stores all the information about the remote servers to be monitored, while the checks table stores the information for the various checks that you’ve added for each of the server (for example, disk space and MySQL).

Lastly, generate the configuration file for the laravel-server-monitor. This will create a config/server-monitor.php file. This is where we can configure the various settings for the library:

    php artisan vendor:publish --provider="Spatie\ServerMonitor\ServerMonitorServiceProvider" --tag="config"

Install the frontend dependencies After installing and configuring the backend dependencies, we can also install the frontend dependencies. First, install the default frontend libraries which Laravel depends on (includes Bootstrap, jQuery, and others):

    npm install

Note: This includes a bunch of libraries which we won’t be using. But we won’t really be importing them in any of our scripts so it’s okay even if we don’t remove them from the package.json file.

Once those are installed, we also need to install our own dependencies:

    npm install --save laravel-echo pusher-js visibilityjs

Here’s a break down of what each one does:

  • laravel-echo - this will let us configure Pusher channels as a broadcaster. You can also use the pusher-js library directly if you’re sure you won’t be needing to use any other realtime subscription channels in the future. Using Laravel Echo is simply a convenience utility for normalizing the APIs.
  • pusher-js - the client-side component of Pusher Channels. Laravel Echo uses it behind the scenes to establish realtime communication between the backend and the frontend.
  • visibilityjs - for listening for when the page visibility changes. This acts as a wrapper to the Page Visibility API so it’s easier to use (normalized API across browsers).

Building the app

Now we’re ready to build the app. We’ll first add the custom system checks, then we’ll create a custom notification channel so that the server has a way of notifying us when the system checks finishes running. After that, we’ll work on the frontend side of the app. Then finally, we’ll add the remote servers to be monitored and run the system checks.

First, open the config/server-monitor.php file and inspect the checks array. These are the server checks that are built into laravel-server-monitor. In this tutorial, we won’t be using elasticsearch and memcached because the remote server that I’ll be using for testing doesn’t have it installed. From here, you can uncomment any checks that you don’t need. Though only do that if you’re sure that you won’t be using it in any of the servers you want to add for monitoring. You can actually disable specific checks to a server that’s already being monitored. I’ll show you how later:

    // config/server-monitor.php
    'checks' => [
      'diskspace' => Spatie\ServerMonitor\CheckDefinitions\Diskspace::class,
      'elasticsearch' => Spatie\ServerMonitor\CheckDefinitions\Elasticsearch::class,
      'memcached' => Spatie\ServerMonitor\CheckDefinitions\Memcached::class,
      'mysql' => Spatie\ServerMonitor\CheckDefinitions\MySql::class,
    ]

Aside from removing unneeded checks, this is also where we can add custom checks for checking if the software you’re using to run the server is running. And that’s exactly what we’ll be doing next. Specifically, we’ll add the following:

  • Check if Apache is running
  • Check if Beanstalkd is running
  • Get the memory usage
  • Get the average CPU usage

Checking if Apache is running First, we’ll add the class for checking if Apache is running. You can do that by creating a SystemChecks folder inside the app directory and inside it create an Apache.php file:

    <?php
    // app/SystemChecks/Apache.php
    namespace App\SystemChecks;
    use Spatie\ServerMonitor\CheckDefinitions\CheckDefinition;
    use Symfony\Component\Process\Process;

    class Apache extends CheckDefinition
    {
      public $command = 'service apache2 status';

      public function resolve(Process $process)
      {
        if (str_contains($process->getOutput(), 'active (running)')) {
          $this->check->succeed('is running');
          return;
        }

        $this->check->fail('is not running');
      }
    }

From the code above, you can see that we need to import both the Spatie\ServerMonitor\CheckDefinitions\CheckDefinition and Symfony\Component\Process\Process class to create a system check class. The class that you create has to extend the CheckDefinition class.

This requires you to add a public $command and implement the resolve() function. The $command, as the name suggests is the command used for checking the status of the software you want to check. Good thing there’s already a built-in diagnostics tool for Apache, so all we have to do is call it from here:

    public $command = 'service apache2 status';

If you execute the same command on the terminal you’ll get an output similar to the following:

Next, inside the resolve() function, we get access to the $process because it’s passed as an argument. From here, all we have to do is check if the output string contains “active (running)”. If you check the terminal output above, it contains that same string in green so we know that the server is running if that’s present in the output. We then call $this->check->succeed('is running') to set the status of the check:

    if (str_contains($process->getOutput(), 'active (running)')) {
      $this->check->succeed('is running'); // set status
      return;
    }

Checking if Beanstalkd is running Create an app/SystemChecks/Beanstalkd.php file and add the following. This does pretty much the same thing as the Apache check. The only difference is the command we’re executing:

    <?php
    // app/SystemChecks/Beanstalkd.php
    namespace App\SystemChecks;
    use Spatie\ServerMonitor\CheckDefinitions\CheckDefinition;
    use Symfony\Component\Process\Process;

    class Beanstalkd extends CheckDefinition
    {
      public $command = 'service beanstalkd status';

      public function resolve(Process $process)
      {
        if (str_contains($process->getOutput(), 'active (running)')) {
          $this->check->succeed('is running');
          return;
        }

        $this->check->fail('is not running');
      }
    }

Getting average CPU usage Create an app/SystemChecks/CPUUsage.php file and add the following. This is a bit different from the previous two because even though we’re extending from the CheckDefinition class, we aren’t actually implementing it 100%. We’re setting an empty command because the Symfony Process component which is used by laravel-server-monitor doesn’t seem to be able to handle piping directly with awk (a text processing tool) for the command line). So what we do is execute the command ourselves instead.

Since there’s usually a threshold in which we consider the CPU to be at a normal operating rate, we also need to add a separate config for that inside config/server-monitor.php. That’s what we’re getting when we call config('server-monitor.cpu_usage_threshold'). There are two thresholds: warn and fail. If the current CPU usage percentage is either of those two, we set the check status to whatever it falls into. Otherwise, we assume that the CPU is operating at a normal rate and set the status to succeed:

    <?php
    // app/SystemChecks/CPUUsage.php
    namespace App\SystemChecks;

    use Spatie\ServerMonitor\CheckDefinitions\CheckDefinition;
    use Symfony\Component\Process\Process;

    class CPUUsage extends CheckDefinition
    {
      public $command = "";

      public function resolve(Process $process)
      {
        $percentage = $this->getCPUUsagePercentage();
        $usage = round($percentage, 2);

        $message = "usage at {$usage}%";
        $thresholds = config('server-monitor.cpu_usage_threshold');

        if ($percentage >= $thresholds['fail']) {
          $this->check->fail($message);
          return;
        }

        if ($percentage >= $thresholds['warning']) {
          $this->check->warn($message);
          return;
        }

        $this->check->succeed($message);
      }

      // next: add code for getting CPU percentage
    }

Here’s the function for getting the CPU percentage. This uses grep to search for lines with the “cpu” text inside the /proc/stat file. After that, we use awk to calculate the usage percentage based on the result we get when we perform arithmetic operations on the second ($2), fourth ($4), and fifth ($5) column of text in that line. Then we simply return the result by using print:

    protected function getCPUUsagePercentage(): float
    {
      $cpu = shell_exec("grep 'cpu ' /proc/stat | awk '{usage=($2+$4)*100/($2+$4+$5)} END {print usage}'");
      return (float) $cpu;
    }

For reference, here’s what the output of cat /proc/stat looks like. So $2 is 11738, $4 is 18979 and so on:

Note: The function above only returns the average CPU usage since the system booted up. This lets us see whether the system is running under tremendous load for a longer period of time. If you need to get the current CPU usage, you need to use something like the top command.

Getting memory usage The last system check that we’ll add is the memory usage. Create an app/SystemChecks/MemoryUsage.php file and add the following. This works similarly to the previous one. The only difference is that we’re now directly reading from the file instead of using grep and awk, we’re using PHP’s fopen() function to read the /proc/meminfo file:

    <?php
    namespace App\SystemChecks;

    use Spatie\ServerMonitor\CheckDefinitions\CheckDefinition;
    use Symfony\Component\Process\Process;

    class MemoryUsage extends CheckDefinition
    {
      public $command = "";

      public function resolve(Process $process)
      {
        $percentage = $this->getMemoryUsage();

        $message = "usage at {$percentage}%";
        $thresholds = config('server-monitor.memory_usage_threshold');

        if ($percentage >= $thresholds['fail']) {
          $this->check->fail($message);
          return;
        }

        if ($percentage >= $thresholds['warning']) {
          $this->check->warn($message);
          return;
        }

        $this->check->succeed($message);
      }

      // next: add code for getting memory percentage usage
    }

Here’s the function for getting the current memory usage. This reads from the /proc/meminfo file. This file contains various information about the system memory. We extract all number instances then divide the active memory usage from the total memory to get the memory in use:

    protected function getMemoryUsage(): float
    {
      $fh = fopen('/proc/meminfo', 'r');
      $mem = 0;
      $all_str = '';

      while ($line = fgets($fh)) {
          $all_str .= $line;
      }
      fclose($fh);

      preg_match_all('/(\d+)/', $all_str, $pieces);

      $used = round($pieces\[0\][6] / $pieces\[0\][0], 2);
      return $used;
    }

For reference, here’s the output of cat /proc/meminfo. The index count starts at 0, so the sixth value is the one beside “Active” and the first value is the one beside “MemTotal”:

Configure server monitor Now that we’ve added all the system checks, it’s time to let laravel-server-monitor know of them. To do that, all we have to do is add them to the checks array. Use a short but descriptive name for the keys and set the path to the class as the value:

    <?php
    // config/server-monitor.php

    return [

      'checks' => [
        'diskspace' => Spatie\ServerMonitor\CheckDefinitions\Diskspace::class,
        'elasticsearch' => Spatie\ServerMonitor\CheckDefinitions\Elasticsearch::class,
        'memcached' => Spatie\ServerMonitor\CheckDefinitions\Memcached::class,
        'mysql' => Spatie\ServerMonitor\CheckDefinitions\MySql::class,

        // add these:
        'apache' => App\SystemChecks\Apache::class,
        'beanstalkd' => App\SystemChecks\Beanstalkd::class,
        'cpu' => App\SystemChecks\CPUUsage::class,
        'memory' => App\SystemChecks\MemoryUsage::class
      ],

      // ...
    ];

At this point, we’re not really done yet. We’ve already added the custom checks but we still haven’t added a way for us to get hold of the data in realtime. That’s what we’ll be doing in the next section.

Create Pusher notification channel The next step is for us to create a custom notification channel. These notification channels automatically get triggered every time the system checks are done executing. By default, laravel-system-monitor uses Slack as a notification channel. We won’t be using it in this tutorial because all we need is realtime monitoring. For that, we will be using Pusher Channels.

    // config/server-monitor.php
    'notifications' => [

      'notifications' => [
        Spatie\ServerMonitor\Notifications\Notifications\CheckSucceeded::class => ['slack'], // we need to update this so it doesn't use slack
      // ...  
    ]

To create a custom notification channel, create a Channels folder inside the app directory and inside it create a PusherChannelsChannel.php file then add the following:

    <?php
    // app/Channels/PusherChannelsChannel.php
    namespace App\Channels;

    use Illuminate\Notifications\Notification;
    use Illuminate\Support\Facades\Cache;
    use App\Events\FinishedCheck;

    class PusherChannelsChannel
    {
      public function send($notifiable, Notification $notification)
      {
        if (Cache::get('page_visibility') == 'visible') {

          $id = $notification->event->check->id;
          $type = $notification->event->check->type;
          $status = $notification->event->check->status;
          $last_run_message = $notification->event->check->last_run_message;
          $host_id = $notification->event->check->host_id;

          event(new FinishedCheck([
            'id' => 'check-' . $id,
            'type' => $type,
            'status' => $status,
            'last_run_message' => $last_run_message,
            'element_class' => numberTextClass($type, $status, $last_run_message),
            'last_update' => now()->toDateTimeString(),
            'host_id' => 'host-' . $host_id
          ]));
        } 
      }
    }

What the above code does is it first checks whether the app dashboard is currently being viewed by the user (on the foreground). If it is, it dispatches the FinishedCheck event. We’ll create this event shortly, for now, know that it’s the one responsible for triggering the message to be sent to the frontend of the app. The message contains the status of a specific system check.

Finished check event In order to send messages to the app’s frontend and update its contents without refreshing the whole page, we need to create an event which will broadcast the message using Pusher Channels. You can create the event using artisan:

    php artisan make:event FinishedCheck

This creates an app/Events/FinishedCheck.php file which has already the basic boilerplate code for broadcasting events in Laravel. Replace the existing code with the following:

    <?php
    namespace App\Events;

    use Illuminate\Broadcasting\Channel; // for broadcasting to a public Pusher channel
    use Illuminate\Foundation\Events\Dispatchable;
    use Illuminate\Broadcasting\InteractsWithSockets;
    use Illuminate\Contracts\Broadcasting\ShouldBroadcast;

    class FinishedCheck implements ShouldBroadcast
    {
      use Dispatchable, InteractsWithSockets, SerializesModels;

      public $message; // the message to be sent to the client side

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

      public function broadcastAs()
      {
        return 'finished.check';
      }

      public function broadcastOn()
      {
        return new Channel('live-monitor');
      }
    }

The most important thing in the above code is that the class should implement the ShouldBroadcast class. This lets Laravel know that this is an event class. If you implement that class, you need to supply the broadcastOn() function. Inside it, all you need to do is return a new Channel instance. This accepts the name of the public Pusher channel where you want to broadcast the event.

    public function broadcastOn()
    {
      return new Channel('live-monitor');
    }

Next, add the $message as a public property for the class. This will contain the actual message to be sent to the frontend:

    public $message;

Lastly, although not required, we’re also setting a broadcastAs() function. This allows us to change the name of the event. By default it will be set to the full path of the class: App\\Events\\FinishedCheck. As you can see, it’s not really that friendly. If you specify the broadcastAs() function, the string that you return from here will be used instead:

    public function broadcastAs()
    {
      return 'finished.check';
    }

Add notification channel Now that we’ve created both the custom notification channel and the event which it dispatches, it’s time to let laravel-server-monitor know of it. Start by importing the PusherChannelsChannel class. Then for each of the items inside the notifications.notifications array, set PusherChannelsChannel::class as an item. This allows us to trigger the event for updating the client-side for each of the available notifications:

    <?php
    // config/server-monitor.php
    use App\Channels\PusherChannelsChannel; // add this

    return [
      'checks' => [
        // ...
      ],

      // ...
      'notifications' => [
        // update this:
        'notifications' => [
          Spatie\ServerMonitor\Notifications\Notifications\CheckSucceeded::class => [PusherChannelsChannel::class],
          Spatie\ServerMonitor\Notifications\Notifications\CheckRestored::class => [PusherChannelsChannel::class],
          Spatie\ServerMonitor\Notifications\Notifications\CheckWarning::class => [PusherChannelsChannel::class],
          Spatie\ServerMonitor\Notifications\Notifications\CheckFailed::class => [PusherChannelsChannel::class],
        ],
        // ...
      ],
      // ...
    ];

While we’re here, you can also add the CPU and memory usage thresholds after the diskspace threshold:

    // ...

    'diskspace_percentage_threshold' => [
      'warning' => 80,
      'fail' => 90,
    ],

    // add these
    'cpu_usage_threshold' => [
      'warning' => 70,
      'fail' => 90,
    ],

    'memory_usage_threshold' => [
      'warning' => 75,
      'fail' => 90,
    ],

Routes Now we’re ready to start working on the frontend of the app. Start by replacing the contents of the routes/web.php file with the following. Below, we’re adding two routes: one for handling the request to the home page of the app and the other for handling the POST request for updating the page visibility status:

    <?php
    Route::get('/', 'MonitorController@index'); // for serving the app dashboard
    Route::post('/page-visibility', 'MonitorController@updatePageVisibility'); // for updating the page visibility

Monitor Controller The next step is to create the MonitorController that we’ve used above. Execute the following command in the terminal to create it:

    php artisan make:controller MonitorController

This will generate an app/Controllers/MonitorController.php file with some minimal boilerplate code for a controller. Clear the contents of the file and add the following instead:

    <?php
    // app/Controllers/MonitorController.php
    namespace App\Http\Controllers;

    use Illuminate\Http\Request;
    use App\Host;
    use Illuminate\Support\Facades\Cache;

    class MonitorController extends Controller
    {
      public function index()
      {
        $hosts = Host::get();
        return view('monitor', [
            'hosts' => $hosts
        ]);
      }

      public function updatePageVisibility()
      {
        Cache::put('page_visibility', request('state'));
        return 'ok';
      }
    }

In the code above, we’ve imported the Host model but we haven’t created it yet. This model represents the hosts table in the database. We’re using it to get the list of hosts (remote servers) that are monitored.

Host model The next thing we need to do is create the Host model:

    php artisan make:model Host

That will create an app/Host.php file. Replace its contents with the following. Below, we’re adding an Eloquent relationship to the App\Check model. This allows us to get the system checks associated with a specific host:

    <?php
    // app/Host.php
    namespace App;

    use Illuminate\Database\Eloquent\Model;

    class Host extends Model
    {
      public function checks()
      {
        return $this->hasMany('App\Check');
      }
    }

Check model Since we’ve already referenced the Check model earlier, we now need to create it:

    php artisan make:model Check

That’s all there is to it. We don’t really need to make any modifications to the boilerplate code. But in case it changes in the future, here’s what it looks like:

    <?php
    // app/Check.php
    namespace App;

    use Illuminate\Database\Eloquent\Model;

    class Check extends Model
    {

    }

Index page At this point we’re now ready to add the HTML code. Create a resources/views/monitor.blade.php file and add the following:

    <!DOCTYPE html>
    <html>
    <head>
      <meta charset="utf-8">
      <meta name="viewport" content="width=device-width, initial-scale=1">

      <meta name="csrf-token" content="{{ csrf_token() }}">

      <title>Live Server Monitor</title>

      <script src="{{ asset('js/app.js') }}" defer></script>

      <link rel="dns-prefetch" href="//fonts.gstatic.com">
      <link href="https://fonts.googleapis.com/css?family=Nunito" rel="stylesheet" type="text/css">

      <link href="{{ asset('css/app.css') }}" rel="stylesheet">

    </head>
    <body>
      <div id="app">
        <header>
          <nav class="navbar navbar-expand-md navbar-light navbar-laravel">
            <div class="container">
              <a class="navbar-brand" href="{{ url('/') }}">Live Server Monitor</a>
            </div>
          </nav>
        </header>

        <main class="py-4 container">
          <div class="row">

            @forelse ($hosts as $host)
              <div class="col">
                <div class="card" style="width: 18rem;">
                  <div class="card-body">
                    <h5 class="card-title">{{ $host->name }}</h5>
                    <h6 class="card-subtitle mb-2 text-muted" id="host-{{ $host->id }}">Last updated: {{ minValue($host->checks) }}</h6>
                    @forelse (onlyEnabled($host->checks) as $check)
                    <ul class="mt-3">
                      <li id="check-{{ $check->id }}">
                        {{ $check->type }}: <span class="{{ $check->type }} {{ numberTextClass($check->type, $check->status, $check->last_run_message) }}">{{ $check->last_run_message }}</span>
                      </li>
                    </ul>
                    @empty
                    <p class="card-text">No checks yet</p>
                    @endforelse
                  </div>
                </div>
              </div>
            @empty
              <p>No hosts yet</p>
            @endforelse

          </div>
        </main>
      </div>

      <script src="{{ asset('js/index.js') }}" defer></script>

    </body>
    </html>

All we’re doing in the above code is looping through all the $hosts that were supplied by the controller. We’re filtering the checks so that it only returns the one’s which are enabled (enabled=1 in the database) using a helper function (onlyEnabled()) which we’ll be creating shortly. We also have a helper function for outputting a specific class based on the status of the system check. For example, if specific software is running, we want to change the text color to green. If not, then we want it to be red. That’s what the numberTextClass() function does.

Helper functions Create a helpers.php file inside the app directory and add the following:

    // app/helpers.php
    function textClass($status, $last_message) {
      if ($last_message == 'is running') { // change text color based on the last message
        return ($status == 'success') ? 'text-success' : 'text-danger';
      }
      return ($status == 'failed') ? 'text-danger' : '';
    }

    function onlyEnabled($collection) { // filter the collection to only the one's which are enabled
      return $collection->filter(function($item) {
        return $item->enabled == 1;
      });
    }

    function minValue($checks) { // used for returning the oldest last_ran_at date
      return min(array_column($checks->toArray(), 'last_ran_at'));
    }

    function numberTextClass($type, $status, $text) { // change text color based on the threshold value
      // these maps to the treshold configs in the config/server-monitor.php`
      $configs = [
        'diskspace' => 'server-monitor.diskspace_percentage_threshold',
        'cpu' => 'server-monitor.cpu_usage_threshold',
        'memory' => 'server-monitor.memory_usage_threshold'
      ];

      preg_match('/(\d+)/', $text, $pieces); // get all the numbers in the text

      if (!empty($pieces)) {
        $number = (float) $pieces[0];
        $config = config($configs[$type]);
        return ($number >= $config['fail']) ? 'text-danger' : (($number >= $config['warning']) ? 'text-warning' : ''); // determine the class to add based on the current percentage value
      }

      return textClass($status, $text); // for the one's whose value isn't percentage based
    }

Since the class we’ve just added needs to be preloaded on every file, we need to update the composer.json file and tell it to autoload the app/helpers.php file:

    {
      // ...
      "extra": {
        // ...
      },
      "autoload": {
          // ...
          "classmap": [
             // ...
          ],
          "files": ["app/helpers.php"] // add this
      },
    }

Save the changes then execute the following command to reload the files that need to be autoloaded:

    composer dump-autoload

Page scripts At this point, we can now add the JavaScript code for receiving the events from the backend as well as updating the page visibility.

Open the resources/js/bootstrap.js file and uncomment the following lines. This allows us to subscribe to the channel that we’ve broadcasted on in the backend earlier:

    // resources/js/bootstrap.js
    import Echo from 'laravel-echo'

    window.Pusher = require('pusher-js');

    window.Echo = new Echo({
      broadcaster: 'pusher',
      key: process.env.MIX_PUSHER_APP_KEY,
      cluster: process.env.MIX_PUSHER_APP_CLUSTER,
      encrypted: true
    });

Next, create a resources/js/index.js file and add the following code. The most important code here is the one where we subscribe to the live-monitor channel. Note that the period before the event name (finished.check) is not a typo. We need to put that to instruct Laravel Echo not to prepend the application’s namespace to the event. From there, we just destructure the message and use the different properties of the message object to update the element which displays the data that we need to update:

    // resources/js/index.js
    // set the CSRF token generated in the page as a header value for all AJAX requests
    // https://laravel.com/docs/master/csrf
    $.ajaxSetup({
      headers: {
        'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
      }
    });

    window.Visibility = require('visibilityjs'); // import the visibility.js library

    // subscribe to the live-monitor channel and listen to the finished.check event
    window.Echo.channel('live-monitor')
    .listen('.finished.check', (e) => {

      const { id, type, last_run_message, element_class, last_update, host_id } = e.message; // destructure the event data

      $(`#${id} .${type}`)
        .text(last_run_message)
        .removeClass('text-success text-danger text-warning')
        .addClass(element_class);

      $(`#${host_id}`).text(`Last update: ${last_update}`);
    });

    // next: add code for updating page visibility

Next, add the code for listening to page visibility changes. Make a POST request to update the status in the backend. This effectively stops the notifications from happening if the state value becomes equal to hidden:

    Visibility.change(function (e, state) {
      $.post('/page-visibility', { state }); // hidden or visible
    });

Lastly, update the webpack.mix.js file to include the resources/js/index.js file for minification:

    mix.js('resources/js/app.js', 'public/js')
        .js('resources/js/index.js', 'public/js') // add this
        .sass('resources/sass/app.scss', 'public/css');

Once that’s added, you can now process the frontend scripts and styles:

    npm run dev

Adding a remote server

laravel-server-monitor comes with an Artisan utility for adding a host. Execute the following on the terminal to add one:

    php artisan server-monitor:add-host

Here’s what adding a host will look like:

You can also do this manually through the database by adding a new entry to the hosts table and adding the checks that you want to the checks table. You can even create your own Artisan command to customize it based on your needs.

Here’s what the checks table looks like. If at some point, you want to disable a specific check that you’ve previously added, you can simply set enabled to 0 or delete the row entirely:

Running the app

Before running the app, you first need to update the .env file with your Pusher app instance credentials:

    BROADCAST_DRIVER=pusher
    QUEUE_CONNECTION=sync

    PUSHER_APP_ID=YOUR_PUSHER_APP_ID
    PUSHER_APP_KEY=YOUR_PUSHER_APP_KEY
    PUSHER_APP_SECRET=YOUR_PUSHER_APP_SECRET
    PUSHER_APP_CLUSTER=YOUR_PUSHER_APP_CLUSTER

    MIX_PUSHER_APP_KEY="${PUSHER_APP_KEY}"
    MIX_PUSHER_APP_CLUSTER="${PUSHER_APP_CLUSTER}"

Once that’s done, access the app on your browser. For me, I used liveservermonitor.loc as the local domain name.

You can manually trigger a system check using the artisan utility provided by laravel-server-monitor:

    php artisan server-monitor:run-checks

Do note that you have to uncomment the line which checks for page visibility in the app/Channels/PusherChannelsChannel.php file for it to work. It wouldn’t really trigger the event if the page is not currently in the foreground:

    if (Cache::get('page_visibility') == 'visible') {
      // ...
    }

Running system checks

The ideal way for us to run the checks is to run them at a specific interval. Laravel already comes with Task Scheduling features. This allows us to run the php artisan server-monitor:run-checks command at a specific interval.

Open the app/Console/Kernel.php file and add the following inside the schedule() function. This will automatically run the command every minute:

    protected function schedule(Schedule $schedule)
    {
      $schedule->command('server-monitor:run-checks')->everyMinute(); // add this
    }

This makes use of crontab so you’ll have to enable it by adding the following to your cron entry file (crontab -e):

    * * * * * cd /path-to-your-project && php artisan schedule:run >> /dev/null 2>&1

At this point, you should now be able to access the app’s dashboard page and the data displayed would refresh every minute.

Conclusion

That’s it! In this tutorial, we’ve built a web app for monitoring the status of your servers in realtime. We’ve used the Laravel Server Monitor package by Spatie to implement most of the functionality. Then we used Pusher Channels to update the server status displayed on the screen in realtime. Lastly, we used the Visibility.js library to check if a user is currently viewing the page where the server status is displayed.

With this knowledge, you’ll now be able to add your own server checks to constantly monitor your servers during times where you expect more traffic than usual. You can also add custom notifications and have the server send you a text message when the CPU usage goes above the threshold that you’ve set.

You can view the full source code of the app on this GitHub repo.

#laravel #php

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Buddha Community

Server health monitoring for Laravel apps | Learning Laravel
Ray  Patel

Ray Patel

1625843760

Python Packages in SQL Server – Get Started with SQL Server Machine Learning Services

Introduction

When installing Machine Learning Services in SQL Server by default few Python Packages are installed. In this article, we will have a look on how to get those installed python package information.

Python Packages

When we choose Python as Machine Learning Service during installation, the following packages are installed in SQL Server,

  • revoscalepy – This Microsoft Python package is used for remote compute contexts, streaming, parallel execution of rx functions for data import and transformation, modeling, visualization, and analysis.
  • microsoftml – This is another Microsoft Python package which adds machine learning algorithms in Python.
  • Anaconda 4.2 – Anaconda is an opensource Python package

#machine learning #sql server #executing python in sql server #machine learning using python #machine learning with sql server #ml in sql server using python #python in sql server ml #python packages #python packages for machine learning services #sql server machine learning services

Carmen  Grimes

Carmen Grimes

1595494844

How to start an electric scooter facility/fleet in a university campus/IT park

Are you leading an organization that has a large campus, e.g., a large university? You are probably thinking of introducing an electric scooter/bicycle fleet on the campus, and why wouldn’t you?

Introducing micro-mobility in your campus with the help of such a fleet would help the people on the campus significantly. People would save money since they don’t need to use a car for a short distance. Your campus will see a drastic reduction in congestion, moreover, its carbon footprint will reduce.

Micro-mobility is relatively new though and you would need help. You would need to select an appropriate fleet of vehicles. The people on your campus would need to find electric scooters or electric bikes for commuting, and you need to provide a solution for this.

To be more specific, you need a short-term electric bike rental app. With such an app, you will be able to easily offer micro-mobility to the people on the campus. We at Devathon have built Autorent exactly for this.

What does Autorent do and how can it help you? How does it enable you to introduce micro-mobility on your campus? We explain these in this article, however, we will touch upon a few basics first.

Micro-mobility: What it is

micro-mobility

You are probably thinking about micro-mobility relatively recently, aren’t you? A few relevant insights about it could help you to better appreciate its importance.

Micro-mobility is a new trend in transportation, and it uses vehicles that are considerably smaller than cars. Electric scooters (e-scooters) and electric bikes (e-bikes) are the most popular forms of micro-mobility, however, there are also e-unicycles and e-skateboards.

You might have already seen e-scooters, which are kick scooters that come with a motor. Thanks to its motor, an e-scooter can achieve a speed of up to 20 km/h. On the other hand, e-bikes are popular in China and Japan, and they come with a motor, and you can reach a speed of 40 km/h.

You obviously can’t use these vehicles for very long commutes, however, what if you need to travel a short distance? Even if you have a reasonable public transport facility in the city, it might not cover the route you need to take. Take the example of a large university campus. Such a campus is often at a considerable distance from the central business district of the city where it’s located. While public transport facilities may serve the central business district, they wouldn’t serve this large campus. Currently, many people drive their cars even for short distances.

As you know, that brings its own set of challenges. Vehicular traffic adds significantly to pollution, moreover, finding a parking spot can be hard in crowded urban districts.

Well, you can reduce your carbon footprint if you use an electric car. However, electric cars are still new, and many countries are still building the necessary infrastructure for them. Your large campus might not have the necessary infrastructure for them either. Presently, electric cars don’t represent a viable option in most geographies.

As a result, you need to buy and maintain a car even if your commute is short. In addition to dealing with parking problems, you need to spend significantly on your car.

All of these factors have combined to make people sit up and think seriously about cars. Many people are now seriously considering whether a car is really the best option even if they have to commute only a short distance.

This is where micro-mobility enters the picture. When you commute a short distance regularly, e-scooters or e-bikes are viable options. You limit your carbon footprints and you cut costs!

Businesses have seen this shift in thinking, and e-scooter companies like Lime and Bird have entered this field in a big way. They let you rent e-scooters by the minute. On the other hand, start-ups like Jump and Lyft have entered the e-bike market.

Think of your campus now! The people there might need to travel short distances within the campus, and e-scooters can really help them.

How micro-mobility can benefit you

benefits-micromobility

What advantages can you get from micro-mobility? Let’s take a deeper look into this question.

Micro-mobility can offer several advantages to the people on your campus, e.g.:

  • Affordability: Shared e-scooters are cheaper than other mass transportation options. Remember that the people on your campus will use them on a shared basis, and they will pay for their short commutes only. Well, depending on your operating model, you might even let them use shared e-scooters or e-bikes for free!
  • Convenience: Users don’t need to worry about finding parking spots for shared e-scooters since these are small. They can easily travel from point A to point B on your campus with the help of these e-scooters.
  • Environmentally sustainable: Shared e-scooters reduce the carbon footprint, moreover, they decongest the roads. Statistics from the pilot programs in cities like Portland and Denver showimpressive gains around this key aspect.
  • Safety: This one’s obvious, isn’t it? When people on your campus use small e-scooters or e-bikes instead of cars, the problem of overspeeding will disappear. you will see fewer accidents.

#android app #autorent #ios app #mobile app development #app like bird #app like bounce #app like lime #autorent #bird scooter business model #bird scooter rental #bird scooter rental cost #bird scooter rental price #clone app like bird #clone app like bounce #clone app like lime #electric rental scooters #electric scooter company #electric scooter rental business #how do you start a moped #how to start a moped #how to start a scooter rental business #how to start an electric company #how to start electric scooterrental business #lime scooter business model #scooter franchise #scooter rental business #scooter rental business for sale #scooter rental business insurance #scooters franchise cost #white label app like bird #white label app like bounce #white label app like lime

Carmen  Grimes

Carmen Grimes

1595491178

Best Electric Bikes and Scooters for Rental Business or Campus Facility

The electric scooter revolution has caught on super-fast taking many cities across the globe by storm. eScooters, a renovated version of old-school scooters now turned into electric vehicles are an environmentally friendly solution to current on-demand commute problems. They work on engines, like cars, enabling short traveling distances without hassle. The result is that these groundbreaking electric machines can now provide faster transport for less — cheaper than Uber and faster than Metro.

Since they are durable, fast, easy to operate and maintain, and are more convenient to park compared to four-wheelers, the eScooters trend has and continues to spike interest as a promising growth area. Several companies and universities are increasingly setting up shop to provide eScooter services realizing a would-be profitable business model and a ready customer base that is university students or residents in need of faster and cheap travel going about their business in school, town, and other surrounding areas.

Electric Scooters Trends and Statistics

In many countries including the U.S., Canada, Mexico, U.K., Germany, France, China, Japan, India, Brazil and Mexico and more, a growing number of eScooter users both locals and tourists can now be seen effortlessly passing lines of drivers stuck in the endless and unmoving traffic.

A recent report by McKinsey revealed that the E-Scooter industry will be worth― $200 billion to $300 billion in the United States, $100 billion to $150 billion in Europe, and $30 billion to $50 billion in China in 2030. The e-Scooter revenue model will also spike and is projected to rise by more than 20% amounting to approximately $5 billion.

And, with a necessity to move people away from high carbon prints, traffic and congestion issues brought about by car-centric transport systems in cities, more and more city planners are developing more bike/scooter lanes and adopting zero-emission plans. This is the force behind the booming electric scooter market and the numbers will only go higher and higher.

Companies that have taken advantage of the growing eScooter trend develop an appthat allows them to provide efficient eScooter services. Such an app enables them to be able to locate bike pick-up and drop points through fully integrated google maps.

List of Best Electric Bikes for Rental Business or Campus Facility 2020:

It’s clear that e scooters will increasingly become more common and the e-scooter business model will continue to grab the attention of manufacturers, investors, entrepreneurs. All this should go ahead with a quest to know what are some of the best electric bikes in the market especially for anyone who would want to get started in the electric bikes/scooters rental business.

We have done a comprehensive list of the best electric bikes! Each bike has been reviewed in depth and includes a full list of specs and a photo.

Billy eBike

mobile-best-electric-bikes-scooters https://www.kickstarter.com/projects/enkicycles/billy-were-redefining-joyrides

To start us off is the Billy eBike, a powerful go-anywhere urban electric bike that’s specially designed to offer an exciting ride like no other whether you want to ride to the grocery store, cafe, work or school. The Billy eBike comes in 4 color options – Billy Blue, Polished aluminium, Artic white, and Stealth black.

Price: $2490

Available countries

Available in the USA, Europe, Asia, South Africa and Australia.This item ships from the USA. Buyers are therefore responsible for any taxes and/or customs duties incurred once it arrives in your country.

Features

  • Control – Ride with confidence with our ultra-wide BMX bars and a hyper-responsive twist throttle.
  • Stealth- Ride like a ninja with our Gates carbon drive that’s as smooth as butter and maintenance-free.
  • Drive – Ride further with our high torque fat bike motor, giving a better climbing performance.
  • Accelerate – Ride quicker with our 20-inch lightweight cutout rims for improved acceleration.
  • Customize – Ride your own way with 5 levels of power control. Each level determines power and speed.
  • Flickable – Ride harder with our BMX /MotoX inspired geometry and lightweight aluminum package

Specifications

  • Maximum speed: 20 mph (32 km/h)
  • Range per charge: 41 miles (66 km)
  • Maximum Power: 500W
  • Motor type: Fat Bike Motor: Bafang RM G060.500.DC
  • Load capacity: 300lbs (136kg)
  • Battery type: 13.6Ah Samsung lithium-ion,
  • Battery capacity: On/off-bike charging available
  • Weight: w/o batt. 48.5lbs (22kg), w/ batt. 54lbs (24.5kg)
  • Front Suspension: Fully adjustable air shock, preload/compression damping /lockout
  • Rear Suspension: spring, preload adjustment
  • Built-in GPS

Why Should You Buy This?

  • Riding fun and excitement
  • Better climbing ability and faster acceleration.
  • Ride with confidence
  • Billy folds for convenient storage and transportation.
  • Shorty levers connect to disc brakes ensuring you stop on a dime
  • belt drives are maintenance-free and clean (no oil or lubrication needed)

**Who Should Ride Billy? **

Both new and experienced riders

**Where to Buy? **Local distributors or ships from the USA.

Genze 200 series e-Bike

genze-best-electric-bikes-scooters https://www.genze.com/fleet/

Featuring a sleek and lightweight aluminum frame design, the 200-Series ebike takes your riding experience to greater heights. Available in both black and white this ebike comes with a connected app, which allows you to plan activities, map distances and routes while also allowing connections with fellow riders.

Price: $2099.00

Available countries

The Genze 200 series e-Bike is available at GenZe retail locations across the U.S or online via GenZe.com website. Customers from outside the US can ship the product while incurring the relevant charges.

Features

  • 2 Frame Options
  • 2 Sizes
  • Integrated/Removable Battery
  • Throttle and Pedal Assist Ride Modes
  • Integrated LCD Display
  • Connected App
  • 24 month warranty
  • GPS navigation
  • Bluetooth connectivity

Specifications

  • Maximum speed: 20 mph with throttle
  • Range per charge: 15-18 miles w/ throttle and 30-50 miles w/ pedal assist
  • Charging time: 3.5 hours
  • Motor type: Brushless Rear Hub Motor
  • Gears: Microshift Thumb Shifter
  • Battery type: Removable Samsung 36V, 9.6AH Li-Ion battery pack
  • Battery capacity: 36V and 350 Wh
  • Weight: 46 pounds
  • Derailleur: 8-speed Shimano
  • Brakes: Dual classic
  • Wheels: 26 x 20 inches
  • Frame: 16, and 18 inches
  • Operating Mode: Analog mode 5 levels of Pedal Assist Thrott­le Mode

Norco from eBikestore

norco-best-electric-bikes-scooters https://ebikestore.com/shop/norco-vlt-s2/

The Norco VLT S2 is a front suspension e-Bike with solid components alongside the reliable Bosch Performance Line Power systems that offer precise pedal assistance during any riding situation.

Price: $2,699.00

Available countries

This item is available via the various Norco bikes international distributors.

Features

  • VLT aluminum frame- for stiffness and wheel security.
  • Bosch e-bike system – for their reliability and performance.
  • E-bike components – for added durability.
  • Hydraulic disc brakes – offer riders more stopping power for safety and control at higher speeds.
  • Practical design features – to add convenience and versatility.

Specifications

  • Maximum speed: KMC X9 9spd
  • Motor type: Bosch Active Line
  • Gears: Shimano Altus RD-M2000, SGS, 9 Speed
  • Battery type: Power Pack 400
  • Battery capacity: 396Wh
  • Suspension: SR Suntour suspension fork
  • Frame: Norco VLT, Aluminum, 12x142mm TA Dropouts

Bodo EV

bodo-best-electric-bikes-scootershttp://www.bodoevs.com/bodoev/products_show.asp?product_id=13

Manufactured by Bodo Vehicle Group Limited, the Bodo EV is specially designed for strong power and extraordinary long service to facilitate super amazing rides. The Bodo Vehicle Company is a striking top in electric vehicles brand field in China and across the globe. Their Bodo EV will no doubt provide your riders with high-level riding satisfaction owing to its high-quality design, strength, breaking stability and speed.

Price: $799

Available countries

This item ships from China with buyers bearing the shipping costs and other variables prior to delivery.

Features

  • Reliable
  • Environment friendly
  • Comfortable riding
  • Fashionable
  • Economical
  • Durable – long service life
  • Braking stability
  • LED lighting technology

Specifications

  • Maximum speed: 45km/h
  • Range per charge: 50km per person
  • Charging time: 8 hours
  • Maximum Power: 3000W
  • Motor type: Brushless DC Motor
  • Load capacity: 100kg
  • Battery type: Lead-acid battery
  • Battery capacity: 60V 20AH
  • Weight: w/o battery 47kg

#android app #autorent #entrepreneurship #ios app #minimum viable product (mvp) #mobile app development #news #app like bird #app like bounce #app like lime #autorent #best electric bikes 2020 #best electric bikes for rental business #best electric kick scooters 2020 #best electric kickscooters for rental business #best electric scooters 2020 #best electric scooters for rental business #bird scooter business model #bird scooter rental #bird scooter rental cost #bird scooter rental price #clone app like bird #clone app like bounce #clone app like lime #electric rental scooters #electric scooter company #electric scooter rental business #how do you start a moped #how to start a moped #how to start a scooter rental business #how to start an electric company #how to start electric scooterrental business #lime scooter business model #scooter franchise #scooter rental business #scooter rental business for sale #scooter rental business insurance #scooters franchise cost #white label app like bird #white label app like bounce #white label app like lime

How to build an learning app like BYJU's| Cost to build app like BYJU's?

Due to schools & Colleges being closed due to Covid-19 Pandemic, the need for e-learning platforms like Byju’s has seen a rapid rise among school students. The rise is so fast that in just 3 months from the beginning of lockdowns its user base increased by twice.

Want to help school students learn with creative methods from an e-learning app?
WebClues Infotech is there for you to bring your vision to reality with its highly skilled e-learning App Development team. With past experience in developing different types of e-learning solutions like AshAce Papers, EduPlay Cloud, Squared, and many more, WebClues Infotech is fully equipped to develop an e-learning app development solution based on your need

Want more information on Byju’s like e-learning app Development?

Visit our detailed guide at https://www.webcluesinfotech.com/how-to-create-an-elearning-app-like-byjus/

#how to build an learning app like byju's? #how to develop a learning app like byju's features & cost #how to create an app like byju's #how much does it cost to develop an app like byjus #e-learning app development solution #e-learning apps development

Fredy  Larson

Fredy Larson

1595059664

How long does it take to develop/build an app?

With more of us using smartphones, the popularity of mobile applications has exploded. In the digital era, the number of people looking for products and services online is growing rapidly. Smartphone owners look for mobile applications that give them quick access to companies’ products and services. As a result, mobile apps provide customers with a lot of benefits in just one device.

Likewise, companies use mobile apps to increase customer loyalty and improve their services. Mobile Developers are in high demand as companies use apps not only to create brand awareness but also to gather information. For that reason, mobile apps are used as tools to collect valuable data from customers to help companies improve their offer.

There are many types of mobile applications, each with its own advantages. For example, native apps perform better, while web apps don’t need to be customized for the platform or operating system (OS). Likewise, hybrid apps provide users with comfortable user experience. However, you may be wondering how long it takes to develop an app.

To give you an idea of how long the app development process takes, here’s a short guide.

App Idea & Research

app-idea-research

_Average time spent: two to five weeks _

This is the initial stage and a crucial step in setting the project in the right direction. In this stage, you brainstorm ideas and select the best one. Apart from that, you’ll need to do some research to see if your idea is viable. Remember that coming up with an idea is easy; the hard part is to make it a reality.

All your ideas may seem viable, but you still have to run some tests to keep it as real as possible. For that reason, when Web Developers are building a web app, they analyze the available ideas to see which one is the best match for the targeted audience.

Targeting the right audience is crucial when you are developing an app. It saves time when shaping the app in the right direction as you have a clear set of objectives. Likewise, analyzing how the app affects the market is essential. During the research process, App Developers must gather information about potential competitors and threats. This helps the app owners develop strategies to tackle difficulties that come up after the launch.

The research process can take several weeks, but it determines how successful your app can be. For that reason, you must take your time to know all the weaknesses and strengths of the competitors, possible app strategies, and targeted audience.

The outcomes of this stage are app prototypes and the minimum feasible product.

#android app #frontend #ios app #minimum viable product (mvp) #mobile app development #web development #android app development #app development #app development for ios and android #app development process #ios and android app development #ios app development #stages in app development