# Laravel : Step by Step Guide to Building Your First Laravel Application

Laravel focuses on the end user first, which means its focus is on simplicity, clarity, and getting work done. People and companies are using it to build everything from simple hobby projects all the way to Fortune 500 companies.

My goal with this Laravel tutorial to create a guide for those just learning the framework. This guide will take you from the very beginning of an idea into a real deployable application.

This look at Laravel will not be exhaustive, covering every detail of the framework, but if you want that I recommend the book Laravel: Up and Running. This tutorial does expect a few prerequisites and here is what you will need to follow along:

• A local PHP environment (Valet, Homestead, Vagrant, MAMP, etc.).
• A database. I’ll be using MySQL.
• PHPUnit installed.
• Node installed.

Note: For the local PHP environment I am using a Mac and Valet because it automatically sets up everything. If you are on Windows, you should consider Homestead or some flavor of a virtual machine.

I am attempting to go through the process of creating a new application just as I would in a real-world environment. In fact, the code and idea are from a project I built.

## Planning

Every project has to start from somewhere, either assigned to you by your work or just an idea in your head. No matter where it originates, thoroughly planning out all the features before you start coding is paramount in completing a project.

How you plan is dependent on how your mind works. As a visual person, I like to plan on paper, drawing out the way I picture the screens looking and then working backward into how I would code it. Others prefer to write a project plan in a text file, wiki, or some mind mapping tool. It doesn’t matter how you plan, just that you do it.

For this guide, we are going to be building a link directory. Here is a list of fundamental goals for this links app:

1. Display a simple list of links.
2. Create a form where people can submit new links.
3. Validate the form.
4. Insert the data into the database.

Let’s get started!

## The First Steps

With a simple plan of attack outlined, it’s time to get a brand new empty project up and running. I like to put all my projects in a ~/Sites directory, and these instructions will use that location. I’ve already “parked” this directory in Valet, so any folders will automatically be mapped to “foldername.test” in the browser.

Open your terminal application and switch into this directory.

mkdir ~/Sites
cd ~/Sites


Next, install Laravel’s command line installer:

composer global require "laravel/installer"


You need to make sure that the global Composer bin is in your path. You can do so by adding the following to your PATH in your ~/.bash_profile or ~/.zshrc if you are using Z shell:

export PATH="$HOME/.composer/vendor/bin:$PATH"


For the path to take effect, you need to restart your terminal session of source the file again:

source ~/.bash_profile


Now you can use the Laravel installer to create new projects from the command line:

laravel new links


This will create a new directory at ~/Sites/links and install an stock Laravel project. Visiting links.test in the browser now shows the default Laravel welcome page:

Now scaffold out the authentication system by running:

php artisan make:auth


Even though this tutorial will not dive into authentication by running this command, it will modify our views and routes. So by doing it early, we don’t have to worry about it messing with any of our code.

With the basics set up and working, it’s time to start doing some coding.

If you start thinking about the whole finished project, it’s easy to get overwhelmed. The best way to fight this is to break everything down into small tasks. So, let’s start by showing a list of links.

Even though showing a list of links sounds like a small task it still requires a database, a database table, data in the table, a database query, and a view file.

Creating a migration will be the first step, and the Laravel Artisan command line tool can help us build that.

php artisan make:migration create_links_table --create=links


Now, open the file this command created. It will be located at database/migrations/{{datetime}}_create_links_table.php.

Inside the up method add our new columns:

Schema::create('links', function (Blueprint $table) {$table->increments('id');
$table->string('title');$table->string('url')->unique();
$table->text('description');$table->timestamps();
});


Save the file and run the migration:

php artisan migrate


While you are working with test data, you can quickly apply the schema:

php artisan migrate:fresh


Next, we need some data and a model to work with our database table. Laravel provides two features which help with this: the first is a database seeder, which populates the database with data, and second, the model factory files that allow us to generate fake model data that we can use to fill our development database and tests:

php artisan make:model --factory Link


The --factory flag will generate a new factory file in the database/factories path, in our case a new LinkFactory file will include an empty factory definition for our Link model.

Open the LinkFactory.php file and fill in the following:

define(App\Link::class, function (Faker $faker) { return [ 'title' => substr($faker->sentence(2), 0, -1),
'url' => $faker->url, 'description' =>$faker->paragraph,
];
});


We use the $faker->sentence() method to generate a title, and substr to remove the period at the end of the sentence. Next, create the link seeder, so we can easily add demo data to the table: php artisan make:seeder LinksTableSeeder  The make:seeder command generates a new database seeder class to seed our links table. Open the database/seeds/LinksTableSeeder.php file and add the following: public function run() { factory(App\Link::class, 5)->create(); }  In order to “activate” the LinksTableSeeder, we need to call it from the main database/seeds/DatabaseSeeder.php run method: public function run() {$this->call(LinksTableSeeder::class);
}


You can now run the migrations and seeds to add data to the table automatically. Using the migrate:fresh command, we can get a clean schema that applies all migrations and then seeds the database:

$php artisan migrate:fresh --seed Dropped all tables successfully. Migration table created successfully. Migrating: 2014_10_12_000000_create_users_table Migrated: 2014_10_12_000000_create_users_table Migrating: 2014_10_12_100000_create_password_resets_table Migrated: 2014_10_12_100000_create_password_resets_table Migrating: 2017_11_03_023418_create_links_table Migrated: 2017_11_03_023418_create_links_table Seeding: LinksTableSeeder  Using the tinker shell you can start playing around with the model data: >>> \App\Link::first(); => App\Link {#747 id: 1, title: "Aliquam quo pariatur", url: "https://gibson.com/consequuntur-consequatur-eius-expedita-maiores-quaerat-occaecati.html", description: "Temporibus eaque aspernatur...", created_at: "2017-11-04 05:35:45", updated_at: "2017-11-04 05:35:45", } >>>  We have the data place and a model to interact with the database. We are now ready to start building the UI to add new links to the application. ### Routing and Views To build out a view showing the list of links, we need to update the main project route and also define a new route that will display our submission form. We can add new routes to our application in the routes/web.php file. In the web routes file you should see the default route below: Route::get('/', function () { return view('welcome'); });  To create a new route we can either use a route closure or a dedicated controller class. In this tutorial, we will use closures for our submission and index routes. First, let’s update the home route by getting a collection of links from the database and passing them to the view: Route::get('/', function () {$links = \App\Link::all();

return view('welcome', ['links' => $links]); });  The second argument can be an associative array of data, and the key ends up being the variable name in the template file. You can also use a fluent API to define variables if you prefer: // with() return view('welcome')->with('links',$links);

// dynamic method to name the variable
return view('welcome')->withLinks($links);  Next, edit the welcome.blade.php file and add a simple foreach to show all the links: @foreach ($links as $link) {{$link->title }}
@endforeach


Here’s what the welcome.blade.php HTML should look like:



@auth
Home
@else
Register
@endauth

@endif

Laravel

@foreach ($links as$link)
{{ $link->title }} @endforeach  If you refresh your browser, you should now see the list of all the links added. With that all set, let’s move to submitting links. ## Displaying the Link Submission Form We are almost done creating our first application in Laravel. We will round out this Laravel tutorial with the ability for others to submit links into the app, which requires three fields: title, URL, and a description. I am a visual person, and before planning out features requiring HTML, I like to draw them out so I can get an idea of what I’m building in my head. Here is a simple drawing of this form: Since we’ve added all the core structure, model factory, migration, and model, in the last section, we can reap the benefits by reusing all those for this section. First, create a new route in the routes/web.php file: Route::get('/submit', function () { return view('submit'); });  Next, we need to create the submit.blade.php template at resources/views/submit.blade.php with the following boilerplate bootstrap markup: @extends('layouts.app') @section('content') Submit a link @if ($errors->any())

Please fix the following errors

@endif

{!! csrf_field() !!}

Title

@if($errors->has('title')) {{$errors->first('title') }}
@endif

Url

@if($errors->has('url')) {{$errors->first('url') }}
@endif

Description
{{ old('description') }}
@if($errors->has('description')) {{$errors->first('description') }}
@endif

@endsection


There’s quite a bit going on in this form, so let’s go over the major points that might be confusing when you are new to Laravel.

Near the top of the form, we have a blade conditional that checks to see if there are any validation errors. When errors exist, the bootstrap alert message will be shown, prompting the user to fix the invalid form fields:

@if ($errors->any()) Please fix the following errors @endif  Each individual form field checks for validation errors and displays an error message and outputs a has-error class:  Title @if($errors->has('title'))
{{ $errors->first('title') }} @endif  If the user submits invalid data, the route will store validation in the session and redirect the user back to the form. The {{ old('title') }} function will populate the originally submitted data. If a user forgot to submit one of the fields, the other fields that have data would be populated after validation fails and errors are shown. If a field has an error, the first() method returns the first error for a given field: {{$errors->first('title') }}


## Submitting the Form

With the form in place, we are ready to handle the POST data and validate data. Back in the routes/web.php file, create another route for the POST request:

use Illuminate\Http\Request;

Route::post('/submit', function (Request $request) {$data = $request->validate([ 'title' => 'required|max:255', 'url' => 'required|url|max:255', 'description' => 'required|max:255', ]);$link = tap(new App\Link($data))->save(); return redirect('/'); });  This route is a little more complicated than the others. First, we are injecting the Illuminate\Http\Request object, which holds the POST data and other data about the request. Next, we use the request’s validate() method to validate the form data. The validate method was introduced in Laravel 5.5 and is a nice shortcut over other methods used for validation. As a bonus, the validated fields are returned to the $data variable, and we can use them to populate our model.

We require all three fields, and using the pipe character; we can define multiple rules. All three rules can have a max of 255 characters, and the url field requires a valid URL.

If validation fails, an exception is thrown, and the route returns the user with the original input data and validation errors.

Next, we use the tap() helper function to create a new Link model instance and then save it. Using tap allows us to call save() and still return the model instance after the save.

Typically, you would have to do the following without tap, it just adds a little syntactic sugar:

$link = new \App\Link($data);
$link->save(); return$link;


If we want to populate a new model with data, we need to allow the fields to be “fillable” via mass assignment. The fillable property is designed to prevent fields from being mass-assigned except for the items you define in the array.

In our case, we are validating each field so allowing them to be mass-assigned is safe. To allow our model to assign values to these fields, open the app/Link.php file and update it to look like the following:

If we wanted to prevent mass-assignment, this is how our code would look:

$data =$request->validate([
'title' => 'required|max:255',
'url' => 'required|url|max:255',
'description' => 'required|max:255',
]);

$link = new \App\Link;$link->title = $data['title'];$link->url = $data['url'];$link->description = $data['description']; // Save the model$link->save();


The last thing we do in our POST route redirects the user back to the home page after saving the link successfully.

## Testing the Form Submission

Laravel makes HTTP testing a breeze for performing integration tests against routes and middleware, so let’s write a few feature tests to verify our code works as expected.

Before we get started, we need to adjust a few things in our phpunit.xml file so that we can use an in-memory SQLite database. You will need to make sure that you have the proper PHP modules installed.

Using environment variables, we can change the database connection by adding a few new variables to the config:

Next, remove the placeholder test that ships with Laravel:

rm tests/Feature/ExampleTest.php


We are ready to start testing the /submit form through HTTP requests to make sure that the route validation, saving, and redirecting are working as expected.

First, let’s create a new feature test to test against our route:

php artisan make:test SubmitLinksTest


The command creates a new testing file with the proper dependencies, including a RefreshDatabase trait that we are going to use to verify that our links are being saved to the database when valid.

Open the new tests/Feature/SubmitLinksTest.php file and let’s define a few skeleton tests in the body of the class that we are going to flesh out:

/** @test */

/** @test */

/** @test */

/** @test */
function max_length_fails_when_too_long() {}

/** @test */
function max_length_succeeds_when_under_max() {}


These tests should give you a high-level overview of what we are going to test:

1. Verify that valid links get saved in the database
2. When validation fails, links are not in the database
3. Invalid URLs are not allowed
4. Validation should fail when the fields are longer than the max:255 validation rule
5. Validation should succeed when the fields are long enough according to max:255.

We might be missing some things, but for your first Laravel application, this is a decent list that should illustrate some basic HTTP testing techniques in Laravel.

The first test we’ll write is the test that verifies that valid data gets stored in the database:

post('/submit', [
'title' => 'Example Title',
'url' => 'http://example.com',
'description' => 'Example description.',
]);

$this->assertDatabaseHas('links', [ 'title' => 'Example Title' ]);$response
->assertStatus(302)

$this ->get('/') ->assertSee('Example Title'); } }  Take note of the RefreshDatabase trait which makes sure that each test has a new database to give each test a pristine database environment with all the migrations. Our first test submits valid post data, which returns a response object that we can use to assert that our route responded as expected. We verify that the database contains a record with the title we just created. Next, we verify that the response was a 302 status code with a Location header pointing to the homepage. Last, we request the home page and verify that the link title is visible on the homepage. ### Testing Failed Validation When a user generally submits bad data, we expect the validation to trigger an exception and we can use that to make sure our validation layer is working: /** @test */ function link_is_not_created_if_validation_fails() {$response = $this->post('/submit');$response->assertSessionHasErrors(['title', 'url', 'description']);
}


We use Laravel’s assertSessionHasErrors() to make sure that the session has validation errors for each of our required fields. Because we submitted empty data to the route, we expect the required rule will trigger for each field.

Let’s run the test suite to verify our work thus far:

$vendor/bin/phpunit PHPUnit 6.4.3 by Sebastian Bergmann and contributors. ... 3 / 3 (100%) Time: 173 ms, Memory: 16.00MB OK (3 tests, 10 assertions)  ### Testing URL Validation We expect only valid URLs to pass validation so that our application doesn’t try to display invalid data. /** @test */ function link_is_not_created_with_an_invalid_url() {$this->withoutExceptionHandling();

$cases = ['//invalid-url.com', '/invalid-url', 'foo.com']; foreach ($cases as $case) { try {$response = $this->post('/submit', [ 'title' => 'Example Title', 'url' =>$case,
'description' => 'Example description',
]);
} catch (ValidationException $e) {$this->assertEquals(
'The url format is invalid.',
$e->validator->errors()->first('url') ); continue; }$this->fail("The URL $case passed validation when it should have failed."); } }  Laravel 5.5 introduced the withoutExceptionHandling() method which disables Laravel’s route exception handling code used to generate an HTTP response after an exception. We use this to our advantage so we can inspect the validation exception object and assert against the error messages. We loop through various cases (add your own if you’d like to cover more scenarios) and catch instances of ValidationException. If the text makes it past the exception handling, we manually fail the test because we expect the route throws a ValidationExcepiton exception each time. The catch block uses the validator object to check the url error and asserts that the actual error message matches the expected validation error message. I like using the try/catch technique, followed by a $this->fail() as a safety harness instead of using exception annotations provided by PHPUnit. I feel catching the exception allows the ability to do assertions that wouldn’t otherwise be possible and provides a more granular control that I like in most cases.

### Testing Max Length Validation

We will test a few scenarios with the max:255 validations rules: when the field fails max-length validation with a length of 256 characters, and when the field is long enough to pass validation at 255 characters.

Although Laravel contains the max validation rule functionality, I like to test it to verify that my application applies the rules. If someone removes the max validation rule, then the tests will catch it.

I like to test the threshold of min and max validation rules as an extra caution to make sure my application respects the min and max boundaries I set.

First, let’s test the “max length” scenario:

/** @test */
function max_length_fails_when_too_long()
{
$this->withoutExceptionHandling();$title = str_repeat('a', 256);
$description = str_repeat('a', 256);$url = 'http://';
$url .= str_repeat('a', 256 - strlen($url));

try {
$this->post('/submit', compact('title', 'url', 'description')); } catch(ValidationException$e) {
$this->assertEquals( 'The title may not be greater than 255 characters.',$e->validator->errors()->first('title')
);

$this->assertEquals( 'The url may not be greater than 255 characters.',$e->validator->errors()->first('url')
);

$this->assertEquals( 'The description may not be greater than 255 characters.',$e->validator->errors()->first('description')
);

return;
}

$this->fail('Max length should trigger a ValidationException'); }  Again, we disable exception handling and create data that is one character too long to pass validation. We assert each field to make sure they all have a max length validation error message. Last, we need to return in the caught exception and use the $this->fail() as a safety harness to fail the test.

Next, we test the “under the max” scenario:

/** @test */
function max_length_succeeds_when_under_max()
{
$url = 'http://';$url .= str_repeat('a', 255 - strlen($url));$data = [
'title' => str_repeat('a', 255),
'url' => $url, 'description' => str_repeat('a', 255), ];$this->post('/submit', $data);$this->assertDatabaseHas('links', $data); }  We make the form data long enough to pass max:255 validation and assert that the data is in the database after submitting the data. Run the test suite and make sure everything is passing: $ vendor/bin/phpunit
PHPUnit 6.4.3 by Sebastian Bergmann and contributors.

......                                                              6 / 6 (100%)

Time: 197 ms, Memory: 16.00MB

OK (6 tests, 17 assertions)


⬆️