Book Image

Building Distributed Applications in Gin

By : Mohamed Labouardy
4 (1)
Book Image

Building Distributed Applications in Gin

4 (1)
By: Mohamed Labouardy

Overview of this book

Gin is a high-performance HTTP web framework used to build web applications and microservices in Go. This book is designed to teach you the ins and outs of the Gin framework with the help of practical examples. You’ll start by exploring the basics of the Gin framework, before progressing to build a real-world RESTful API. Along the way, you’ll learn how to write custom middleware and understand the routing mechanism, as well as how to bind user data and validate incoming HTTP requests. The book also demonstrates how to store and retrieve data at scale with a NoSQL database such as MongoDB, and how to implement a caching layer with Redis. Next, you’ll understand how to secure and test your API endpoints with authentication protocols such as OAuth 2 and JWT. Later chapters will guide you through rendering HTML templates on the server-side and building a frontend application with the React web framework to consume API responses. Finally, you’ll deploy your application on Amazon Web Services (AWS) and learn how to automate the deployment process with a continuous integration and continuous delivery (CI/CD) pipeline. By the end of this Gin book, you will be able to design, build, and deploy a production-ready distributed application from scratch using the Gin framework.
Table of Contents (16 chapters)
1
Section 1: Inside the Gin Framework
3
Section 2: Distributed Microservices
9
Section 3: Beyond the Basics

What is Gin?

Before deep diving into the Gin web framework, we need to understand why Go is a top choice when it comes to building scalable and distributed applications.

Go (also referred to as Golang) is an open source programming language, developed by Robert Griesemer, Rob Pike, and Ken Thompson within Google in 2007. It is a compiled, statically typed language designed to enable users to easily write reliable, scalable, and highly efficient applications. The key features of Go are as follows:

  • Simple and consistent: Go has a rich set of library packages with powerful standard libraries for testing, error management, and concurrency.
  • Fast and scalable: Go is a general-purpose programming language developed for the multi-core reality of today's computers. It has built-in concurrency with Goroutines and channels. Goroutines provide lightweight, threaded execution. Declaring a Goroutine is as simple as adding the go keyword before a function.
  • Efficient: Go provides efficient execution and compilation. Go is also statically linked, which means that the compiler invokes a linker in the last step that resolves all library references. This means we would get one binary executable after compiling a Go program with no external dependencies. Moreover, it offers efficient memory utilization with a built-in garbage collector (Go exhibits many similarities with low-level programming languages such as C or C++).
  • Community and support: Go is backed by Google and has an ever growing ecosystem and numerous contributors to the language on GitHub. Moreover, many online resources (tutorials, videos, and books) are available for getting started with Go.

Go has become hugely popular among enterprises and the open source community. Based on the StackOverflow Developer Survey 2020 (https://insights.stackoverflow.com/survey/2020), Go is in the top 5 of the most loved programming languages:

Figure 1.1 – Most loved programming languages according to the StackOverflow Survey 2020

Figure 1.1 – Most loved programming languages according to the StackOverflow Survey 2020

Golang is known to be the number one choice when it comes to building large-scale, complex tools and cloud-based applications. The following image highlights the main open source projects that have been developed using Go:

  • Docker: A solution that's used to create, deploy, and run applications using containers.
  • Kubernetes: A container orchestration platform for managing containers across a fleet of nodes/machines.
  • Etcd: A reliable distributed key-value store used to store data for a distributed system or application.
  • InfluxDB: A scalable time-series database designed to handle high write and query loads.
  • CoreOS: A lightweight operating system designed to deploy container-based applications.
  • Terraform: An infrastructure-as-code tool for building, changing, and versioning cloud infrastructure.
  • CockroachDB: A cloud-native SQL database for data-intensive applications.
  • Consul: A distributed store with service discovery, service mesh, and health check monitoring capabilities:
Figure 1.2 – Open source tools powered by Go

Figure 1.2 – Open source tools powered by Go

As we can see, Go is a solid language for distributed systems and infrastructure tools. Docker, Kubernetes, Prometheus, and others are built using Go.

Go is also known for building web applications of all shapes and sizes. This is partly due to the fantastic work that has been put into making the standard library clean, consistent, and easy to use. Perhaps one of the most important packages for any budding Go web developer is the net/http package. This package allows you to build HTTP servers in Go with its powerful compositional constructs.

To build a web application, you'll need to build an HTTP server. The client (for example, a browser) makes an HTTP request with some information; the server then processes that request and returns a response. The response can be in JSON, XML, or HTML format:

Figure 1.3 – HTTP client-server communication

Figure 1.3 – HTTP client-server communication

This pattern of request-response is one of the key focal points in building web applications in Go.

While the net/http package allows you to craft a web application easily, the routing mechanism is not so powerful, especially for complex applications. That's where a web framework comes into play. The top Golang web frameworks are listed in the following table:

Gin is possibly the most used and largest running Go web framework. The framework has already harvested 48,210 stars and 5,100 forks in GitHub, which shows that the framework is very popular. This modular framework can be extended easily with minimal fuss. It is great to use because many components can be reused with a direct net/http package.

Important note

Another strong but conservative framework is Gorilla/Mux. It has one of the biggest online communities with many resources on the internet to teach you how to build end-to-end web applications.

According to the official documentation https://gin-gonic.com/docs/, Gin is described as follows:

"Gin is an HTTP web framework written in Go (Golang). It features a Martini-like API with much better performance -- up to 40 times faster. If you need smashing performance, get yourself some Gin".

Gin is a minimalistic web framework suitable for building web applications, microservices, and RESTful APIs. It reduces boilerplate code by creating reusable and extensible pieces of code: you can write a piece of middleware that can be plugged into one or more request handlers. Moreover, it comes with the following key features:

  • Well documented: The documentation for Gin is broad and comprehensive. Most tasks that you will need to do relating to the router can be found easily in the docs.
  • Simplicity: Gin is a pretty minimalistic framework. Only the most essential features and libraries are included, with little to no boilerplate to bootstrap applications, making Gin a great framework for developing highly available REST APIs.
  • Extensible: The Gin community has created numerous pieces of well-tested middleware that make developing for Gin a charm. Features include compression with GZip, authentication with an authorization middleware, and logging with external solutions such as Sentry.
  • Performance: Gin runs 40x faster than Martini and runs comparatively well compared to other Golang frameworks. The following is the results of a benchmark I ran against multiple Go libraries:
Figure 1.4 – Golang web framework benchmarks

Figure 1.4 – Golang web framework benchmarks

Important note

This benchmark was performed on a macOS High Sierra, 2.7 GHz Intel Core i7, 16 GB DDR3 computer, with Go 1.15.6 as the runtime environment.

That being said, before you can write your first line of Go code, you'll need to set up the environment. Let's start by installing Go.