Faker Gem: Fake Data Generation in Ruby.

Gems are libraries in Rails that generally enable you to write the application code faster and thereby making a great product in far lesser time. Usually, whenever we start developing any application, there comes a point when we need data which we can use to see how the application will behave while doing some load testing or how it would look when we deploy it to the production. The manual process of creating the data can be daunting. Faker gem serves to take this pain away by generating the fake data just as needed and saving us all the time and effort otherwise wasted in the manual process of data-generation.

It can generate almost any kind of data suitable for our application. For example, it can generate the fake data for fields such as name, email, passwords, phone-numbers, paragraphs, etc. It is therefore, an awesome way of populating the model (which is a database layer in Rails)

Let’s take a look at this gem by creating a sample project.

Open the Gemfile from application directory and add ‘gem faker’ as shown below.

File name: Gemfile

Run the command ‘bundle install’ as always.

Just to confirm and see if the gems installed successfully.

So, the installation was successful! Now, let’s create a model for which we will do the data
population using faker gem. We will call our sample model as PersonDetail & it will have the following fields:

1. First Name
2. Last Name
3. Age
4. Email
5. Phone Number
6. Company Info

As we have used the scaffolding for faster demonstration, the table with name ‘’person_details’’ with mentioned fields will be created after migrating the database.

At this point, we should have the table created with the mentioned fields. We can check the actual structure of this table in schema.rb file

File name : db/schema.rb

Now, there is a file called seeds.rb present in application directories ‘db’ folder. There are
Some examples already available (the commented part) in this file that demonstrates how to make use of this file.
We can also go ahead on the same lines and try to create data for defined fields in “person_details” table by using Faker gem.

THE ACTUAL USAGE OF FAKER STARTS FROM HERE!

We have some common fields such as FIRST_NAME, LAST_NAME, EMAIL, PHONE_NUMBER, etc. in our table. For these fields, the usage is, as shown below:

Faker::Name.first_name → first_name
Faker::Name.last_name → last_name
Faker::Number.number(2) → age
Faker::Internet.email → email
Faker::PhoneNumber.phone_number → phone_number
Faker::Company.name → company_info

All these values will be generated in random ways to achieve considerable uniqueness in the data generated.
Combining all of these fields, we can make it to create as many number of rows as we want in person_details table.

File name : db/seeds.rb

And here is the final step for data generation:

We can start the server as “rails server” and enter the route as

There we go! We can see that 5 distinct rows are created and shown on the index listing page:

Now, while Faker generates the information in random ways, the data generated by default may or may not be completely unique all the time. To ensure that the data generated is unique at all times, we can make use of ‘unique’ just before the actual field call:

There are many such fields for which we can have fake data. You can find an exhaustive list of the same here:

https://github.com/stympy/faker

Stay tuned for more!

--

--

--

Ruby on Rails Development Company

Love podcasts or audiobooks? Learn on the go with our new app.

Recommended from Medium

January|Dante Network Fortnightly Report 01.15–01.31, 2022

Data Analysis — SQLite3 in python

An open letter from FreeTON Community to the game developer, Epic Games

How to use Streamlit, Pandas and Plotly to create an interactive dashboard with earthquake data…

Deploy Python + Tesseract + OpenCV Fast API using AWS EC2 Instance

Python — Creating a directory

Welcoming FhaeLin to Main Menu!

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
RailsCarma

RailsCarma

Ruby on Rails Development Company

More from Medium

ActiveRecord pitfall that could cause a disaster

💎 Ruby Radar #48 — Companions we made along the way

Hitting the ground running on a Ruby Sinatra project

Ruby on Rails — Migration