What is Ruby Gem?

What is a Ruby Gem?

Ruby Gems are open-source libraries containing Ruby code and packed with some additional data. A gem allows a programmer to utilize the code included within the gem in their program without having to explicitly enter that code. It facilitates code sharing among developers by making it simpler for them to maintain dependencies across different libraries and functionality.

Structure of Ruby Gem

The Ruby Gems follow a well-defined structure. Each Ruby Gem contains a name, version, and platform.

They follow the same basic code organization structure:

Some of the major components of the Ruby Gem file are as follows

• lib: The gem's source code is located in the lib directory.
• test or spec: Depending on the test framework the developer uses, tests can be found in either the test or spec directory.
• Rakefile: This is used to do many activities, including automated tests.
• bin: The executable file that the gem includes in the bin directory will be added to the user's PATH when the gem is installed.
• README: The README file typically contains the documentation.
• Gemfile: This file contains a list of all dependencies needed by the Ruby Gem
• gemspec: This file contains the metadata for the Ruby Gem. Gem files, test details, platform, version number, author's email, and phone are just a few of the items kept here.

Gemspec

The Gemspec file stores the metadata for the Gem. Information such as a gem's name, version, description, authors, and homepage are all specified in the gemspec document.

Let's look at an example of a Gemspec file:

It typically includes the following information:

• Name: The ruby gem's name.
• Version: The Ruby Gem's version number.
• Summary: A summary of Ruby Gem's functionality.
• Description: A thorough explanation of Ruby Gem's features.
• License: The terms of Ruby Gem's distribution license.
• Authors: The Ruby Gem's creators.
• Email: The writer's email addresses.
• Homepage: Ruby Gem's home page.
• Dependencies: The list of dependencies required by the Ruby Gem.

Installing Ruby Gem

The gem command can be used to install a Ruby Gem. Simply open the command prompt or terminal and enter the following command to install a Ruby Gem:

The <gem_name> is the name of the Ruby Gem that we want to install. The gem command will download and install the Ruby Gem, along with all its dependencies, if any.

How to Use Gem in Ruby

To use a gem in a Ruby file, we should include the gem at the beginning of the file. To do this, we need to insert the following line at the start of the Ruby file:

The <gem_name> is the name of the Ruby Gem that we want to use in the Ruby program. Once we have included or imported the Ruby Gem in our code, we can use its functionality and features in our program.

Simplifying Gem Sharing with Ruby Gem

Ruby Gem package manager makes the process of sharing code with other fellow developers simple and smooth. Developers can easily share code with others by packing their code into Gems using Ruby Gems. It allows developers to reuse more code and as a result, the dependencies between various libraries also become simple. Before the usage of the Ruby Gem, the codes written in Ruby were shared among developers manually. It was a slow and inefficient process that was heavily error-prone. Developers had to manually convert their code into zip files and share them with others. With the introduction of Ruby Gem, the process of sharing Ruby code has become streamlined and simple. Developers can now quickly generate Gem files containing their code and all of its dependencies. The code from these Gems can then be simply installed by other developers using the gem command.

How was Ruby without RubyGem?

Ruby was used even before the creation of RubyGems. At that time developers had to manually install and manage libraries and dependencies for their projects because there wasn't a centralized package management system like RubyGems. As developers had to find and download the required code from numerous sources and make sure that all dependencies were correctly loaded and configured, this process was time-consuming and error-prone. It was more challenging to find new libraries and collaborate with other developers for any updates or issues. It was thus a frustrating and time-consuming process for developers.

The introduction of Ruby Gems significantly streamlined the development process by providing a consistent and simpler way for developers to exchange and reuse others' codes as well as improve others' codes.

Solving Gem Dependencies with Bundler

Ruby Gem makes it easier for developers to handle dependencies across different libraries and functions. But managing the dependencies of several Gems within a single application can still be very difficult. It is such a challenging task to organize gems and version dependencies as some gems could only be used with some specific versions of other gems.

This problem is solved by Bundler. It is a tool that has been designed to make the process of handling multiple gem dependencies within a single application smooth.

Let's look at an example of a Gem file:

After creating the Gemfile, we can run bundle install in our terminal to install all of the gems and their respective dependencies. This will also generate a Gemfile. lock file with the exact versions of all installed gems and their dependencies.

Using Bundler is simple. First, it is necessary to install it, and because Bundler is a gem itself, we can do so with gem install bundler. With Bundler installed, you can use any gem in your project in 2 steps:

• Add the gem to a Gemfile in your project’s root
• Run bundle install in your terminal