Building Scalable Microservices with Go and Gin
The Shift to Microservices Architecture
In the past, developers built cloud-based applications using a monolithic architecture, where the entire application logic was embedded into a single process and ran on a single server computer. However, this approach created scaling challenges and maintainability problems for modern web application backends. Today, almost all developers use microservices architecture to overcome these issues.
Introducing Go and Gin
One way to build microservices is by using Go, a fast, simple, general-purpose, and developer-friendly programming language. We can also utilize the Gin framework, which offers every feature needed for building RESTful modern microservices.
Gin Framework Features
Gin is a fully-featured, high-performance HTTP web framework for the Go ecosystem. Its popularity is growing daily among Go developers due to its features, including:
- High-performance HTTP routing
- Flexible, extendable, and developer-friendly API
- XML/JSON/YAML/ProtoBuf rendering
- Error management and logging
- JSON validation
- Static file serving features
Getting Started with Gin
To get started with the Gin framework, we need to set up our development environment. First, ensure that your computer has Go ≥ v1.13 installed. Then, initialize a new Go project to use remote dependencies and download the Gin framework package.
Building a Simple Microservice
Let’s create a simple microservice to get started with the framework. Add the following code to the main.go source file:
“`go
package main
import (
“github.com/gin-gonic/gin”
)
func main() {
r := gin.Default()
r.GET(“/hello”, func(c *gin.Context) {
c.JSON(200, gin.H{“message”: “Hello, World!”})
})
r.GET(“/os”, func(c *gin.Context) {
c.String(200, “Your operating system is ” + runtime.GOOS)
})
r.Run(“:8080”)
}
“
This code defines two HTTP GET endpoints:and/os. The/helloendpoint returns a JSON formatted message, while the/os` endpoint returns the current operating system name in plain text format.
Structuring Microservices with Routes
We can create a microservice with just one endpoint to execute a single action, like the well-known serverless concept. However, we often let microservices perform multiple actions. For example, you may build a microservice to get product details, add new products, and remove existing products.
Accepting, Processing, and Responding
Every RESTful microservice performs three key actions: accepting data, processing/handling data, and returning data. Microservices typically send responses to external environments, such as web or mobile apps, but they can communicate with each other too.
Validating Incoming Requests
Microservices can handle various incoming requests. To ensure that requests are valid, we can use Gin’s struct-tag-based validation feature to implement validation with less code.
Extending Gin with Middleware
Middleware refers to components that act between two connected software components. Gin’s middleware system lets developers modify HTTP messages and perform common actions without writing repetitive code inside endpoint handlers.
Microservice-to-Microservice Communication
External application clients usually connect and communicate with microservices directly or via API gateway-like services. We can quickly build synchronous, HTTP-based inter-service communication with Gin.
Project Structuring and Microservice Best Practices
When working with Gin-based microservices, follow these best practices:
- Use the MVC pattern principles to structure your code
- Implement custom middleware if you feel that you’re writing repetitive code inside endpoint handlers
- Handle errors properly during inter-service communication
- Write critical situations in a log file
By following these guidelines and using the Gin framework, you can build scalable and maintainable microservices with ease.