Tutorial by Examples: r

Let use 'os_server' command from module 'Cloud' [http://docs.ansible.com/ansible/os_server_module.html]. Variables are defined in ./group_vars/all. $vi launch_compute.yml - name: launch a compute instance hosts: localhost gather_facts: False tasks: - name: Create and launch the VM ...

Use the 'os_server_facts' command from module 'Cloud' [http://docs.ansible.com/ansible/os_server_module.html]. Variables are defined in ./group_vars/all and the instance name is in server: "MyOwnPersonalInstance". $vi get_compute_info.yml - name: Get and print instance IP hosts: loca...

Instead of printing all the informations, we print only IP address of the first instance whose name is "MyOwnPersonalInstance". It's usually all we need. $vi get_compute_ip.yml - name: Get and print instance IP hosts: localhost gather_facts: False tasks: - name: Get VM infos...

To delete our instance, reuse the os_server command with all authentication information and simply replace ' state: present' by ' state: absent'. $vi stop_compute.yml - name: launch a compute instance hosts: localhost gather_facts: False tasks: - name: Create and launch the VM os_...

This guide is explicitly for PostgreSQL 9.1 or higher on linux machines. It uses the postgres extensions-feature that will greatly improve the import of extensions to an existing postgres-installation. If you have to work with an older version of postgres, please refer to the official documentations...

The Laravel framework has a few system requirements. Of course, all of these requirements are satisfied by the Laravel Homestead virtual machine, so it's highly recommended that you use Homestead as your local Laravel development environment. However, if you are not using Homestead, you will need t...

If you have PHP installed locally and you would like to use PHP's built-in development server to serve your application, you may use the serve Artisan command. This command will start a development server at http://localhost:8000: php artisan serve Of course, more robust local development option...

The basic example Open routes/web.php file and paste the following code in file: Route::get('helloworld', function () { return '<h1>Hello World</h1>'; }); here 'helloworld' will act as page name you want to access, and if you don't want to create blade file and still want to ...

Open routes file. Paste the following code in: Route::get('helloworld', function () { return '<h1>Hello World</h1>'; }); after going to route http://localhost/helloworld it displays Hello World. The routes file is located /routes/web.php

Accessing pages and outputting data is fairly easy in Laravel. All of the page routes are located in app/routes.php. There are usually a few examples to get you started, but we're going to create a new route. Open your app/routes.php, and paste in the following code: Route::get('helloworld', functi...

Bullet This one particularly blew my mind. The bullet gem helps you kill all the N+1 queries, as well as unnecessarily eager loaded relations. Once you install it and start visiting various routes in development, alert boxes with warnings indicating database queries that need to be optimized will p...

In this example we will set up a geospatial database, import data from 2 different sources, and view the results in an application called QGIS. This guide is explicitly written for linux-machines, if you operate on another platform, some commands or paths might not work as expected. In order to vie...

Backreferences "Backreferences" are references in a search regex to capture groups in the same search regex. The "search regex" is the regex used in the "Find" field of the Find/Replace dialog box. Here is the most common backreference syntax: Absolute: (group one)...

A regex in Notepad++ may have as many capture groups as desired. (one)(two)(three)...(nine)(more than nine groups!)... Anonymous capture groups use the standard syntax: (group) Named capture groups may use either of following syntax formats: (?<name>group) (?'name'group) Anonymo...

Typically we represent an anary tree (one with potentially unlimited children per node) as a binary tree, (one with exactly two children per node). The "next" child is regarded as a sibling. Note that if a tree is binary, this representation creates extra nodes. We then iterate over the s...

The color schemes changes the colors of the code. They can change, for example, with which color the keywords are highlighted, with which color the line the caret is on is highlighted (needs highlight_line to be set to true in the preferences (not part of the cojor scheme)), what is the color of the...

Along with other more advanced text editors, Atom allows developers to open a single file or a directory. Opening Files To open files with Atom, either use File > Open File... in the menu as show below: or use the faster keyboard shortcut: Ctrl+O (For Mac OS: ⌘+O). This will open a file expl...

In order to keep track of your projects' file structure, Atom, like many text editors and IDEs, uses a file tree model. These trees show the locations and names of your files and directory. To toggle the tree between visible and hidden, the keys Ctrl+\ may be used (⌘+\ for Mac OS). This tree also in...

<table> <thead> <th>Name</th> <th>Index</th> </thead> <tbody> <tr *ngFor="let hero of heroes"> <td>{{hero.name}}</td> </tr> </tbody> </tabl...

The primary reason to use interfaces to achieve polymorphism and provide developers to implement on their own way in future by implementing interface's methods. Suppose we have an interface and three classes: interface Connector{ doConnect(): boolean; } This is connector interface. Now we...