10 => Models, Views & Controllers

-

 This blog will cover the basics of what the MVC pattern is and how Laravel implements the pattern. The beginning of this entry will provide a high level overview of the pattern and will dive into some helpful functionality that Laravel provides that makes using the pattern easier.

Model

The applications models contain the applications main business logic. They are the main part of the application. The controllers delegate jobs to models and return views to the client.

Models can be created using the artisan command 
    php artisan make:model [name]

By including the -c flag the previous command will make a Controller for that given model with CRUD methods scaffolded. 
    php artisan make:model [name] -c

The applications models can be found in 
    app_route / app / models

View

The view is what the user interacts with, in the case of web application it is the HTML that is served to the client. Views are served to the client by controllers.

The applications views can be found in 
    app_route / resources / views

Controller

Controllers handle the delegation of tasks like handing off jobs to models to perform, rendering views with data and returning them to the client. Controller logic should be lightweight and should require minimal modification when changes are made, with most of the changes being done inside models.

Controllers can be created using the artisan command 
    php artisan make:controller --model=[ModelName] [ControllerName]

The CRUD methods that are found in generated controllers represent certain CRUD actions.
    index () -> Render a list of resources
    show () -> Render a single resource
    create () -> Render a view to create a new resource
    store () -> Persist the new resource
    edit () -> Render a view to edit an existing resource
    update () -> Persist the edit to the existing resource
    destroy () -> Delete a resource

The applications controllers can be found in 
    app_route / app / Http / Controllers

Routes

The web server listens for traffic on different 'routes' and maps these routes to actions on a controller. 
The task ID that is provided in the route is automatically fetched from the database when a request is sent to the /tasks/{task} route. If the route /tasks/1 receives a request then the task with ID 1 is fetched from the database and is available throughout the update method.

Validation

When a request is received by a controller the data passed in can be validated by functionality provided by Laravel. Multiple validation criteria can be provided to each data point by grouping them into an array, although the following only validates each piece of data against one criterion.

Concluding Remarks

Laravel implements the standard MVC pattern with some extra built in features that make managing the flow of data easier, although certain practices must be adhered to in order for this to work properly. This forces developers to learn these practices however means that moving from project to project is an easier process as because there are common features across projects.

Comments

Post a Comment

Popular posts from this blog

8 => Gates & Authorization Policies

-
Image
Determining whether or not a user is allowed to perform a certain action is an important aspect of building a CMS. It provides users with ownership of their data, preventing other users from performing CRUD functionality on data that should be hidden from them. This is more commonly referred to as authorization. Laravel accomplishes this job by using gates and/or policies . This blog entry will cover how gates are used in the KANBAN application. Only one example will be covered as the process is the same for creating different gates for different actions. Workflow There are multiple steps involved when attempting to secure actions. There are shortcuts that can be taken to reduce the number of these steps however in doing so the applications logic becomes less manageable as some methods could become 'fat'. This makes the code harder to understand. Initially the developer should create a security policy, these are stored in app_route/app/Policies and follow the xPolicy.php conven...
Read more

4 => Views - Templates, Components & Pagination

-
Image
This blog entry will discuss views, more specifically Blade Templates, and how I implemented pagination. The creation of views, templates and dynamically rendering content for the client will be covered throughout this entry. I'll also discuss some of the problems I faced while attempting to use views and how I overcame those problems. Views In its most basic description, views are what the customer is served, it is the HTML page that the customer interacts with on their client. Laravels Blade files provide functionality that vanilla php can provide however it provides a consistent and straightforward method in doing so. An example of this is @foreach loops and the displaying of error messages using @error. Laravel allows for views to be constructed in several ways. Vanilla php ( You are not forced to use .blade.php files ) Laravel Blade templates Plain HTML ( Doing this you lose most of the functionality php provides however if a page is static and the content never changes this i...
Read more

5 => User Accounts & Authentication

-
Image
Implementing Authentication In Laravel This entry to the blog will explain how I personally went about adding authentication into an existing application along with the issues I faced. I'll be covering both the good and bad, what I found intuitive and where I feel that Laravel could potentially improve and why. Database Table Structure So far the project already has a users table that were generated by default. This table is already suitable providing the appliation what it requires for authentication, the application just needs the logic for authentication. Each users table has the following general structure : The following is an example of some data that has been generated with Faker through the use of Factories( you can read more about factories in blog #6 ). You'll notice that every password is identical, at the moment as they are hardcoded. The pre-hashed version of the password is the word 'password' so that while testing functionality I don't need to rememb...
Read more