> For the complete documentation index, see [llms.txt](https://prospect-io.gitbook.io/developer-playbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prospect-io.gitbook.io/developer-playbook/our-stack/ruby-on-rails.md).

# Ruby on Rails

Ruby on rail is our main backend framework at Overloop

### The Magic Ingredient

3 words: **Conventions over configuration**.

## Basics

{% embed url="<https://rubyonrails.org/>" %}

Ruby on Rails (also known as rails) is a web application framework (backend), which presents as a set of ruby gems (aka libraries).&#x20;

## Code Organization&#x20;

![](https://i.pinimg.com/originals/13/52/92/1352927bf6c754be8abad20bbf1b7bac.png)

### Framework

Rails organization is made around some main components, making what we call the *MVC framework*:&#x20;

* **Model** : The representation of the data stored in the database
* **View** : Something that we can display &#x20;
* **Controller** : The logic for handling a web request&#x20;

At Prospect, we don't really use the *View* part of Rails, since we're using Ember for the frontend, and reserve it for a very little subset of elements (mails, PDFs, ...). That's the *API* configuration of Rails.&#x20;

Apart from that, Rails also includes a set of other components:&#x20;

* **ActiveJob** : A system for background action processing
* **ActiveMailer** : A system to send mails
* **ActiveRecord**: A full featured ORM&#x20;
* **ActiveStorage** : A system to attach files to models

### Components

Rails also come with some components:&#x20;

* **Puma**: A web server for running rails&#x20;
* **Rake** : A system for running tasks&#x20;
* **The rails console**: An interpreter of ruby code, which runs in the context of the current rails app (with all models loaded, ...)&#x20;

## MVC & Service Oriented Architecture

To implement that in Rails, we decided to split our code in two parts:&#x20;

#### **Business logic:**&#x20;

* models
* services

#### **Technical elements:**

All the technical components of our applications that do not relate to business logic:

* controllers&#x20;
* params
* serializers
* commands&#x20;
* jobs&#x20;
* libraries

**Rules**

We define strict rules on the roles of each elements:&#x20;

* controllers: handle an HTTP request
* params: parse & validate the HTTP parameters
* commands: call services and format their results
* models: represent database information (and should be **as simple as possible**)
* services: perform business logic (that's were the complex parts go)
* jobs: for asynchronous processing
* libraries: for **non-domain-related** utilities (like text processing)

The relation between those elements is unidirectional: **technical elements can call business logic, but not the opposite**.

![Source: https://study.dnsimple.com/resources/maintaining-rails-hanami/](https://434471908-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LsMtxmH6ixcLmlwG2Vl%2F-LwI3laGfGq_S9TtYwug%2F-LwI5J1Z3jXDuuzZfyYk%2FCapture%20d%E2%80%99e%CC%81cran%202019-12-17%20a%CC%80%2010.01.26.png?alt=media\&token=63c86b1b-aa34-4fee-8c2b-bff1b97c1481)

As you can see, we use a variety of classes to implement this **service oriented architecture**.&#x20;

We will talk about each and every one of them in the subsection of this page. It will allow you to see how we implemented our framework and see a complete flow of execution.&#x20;

**If you discover Rails and our framework for the first time, we highly recommend you to check these out**. You can start by learning about [controllers](/developer-playbook/our-stack/ruby-on-rails/controllers.md), then just continue the flow from there.

## References

### Documentation

{% embed url="<https://api.rubyonrails.org/v5.2.3/>" %}

{% embed url="<https://guides.rubyonrails.org/v5.2/>" %}

### Interesting newsletters

{% embed url="<https://rails-weekly.ongoodbits.com/>" %}