How do I read environment variables and configuration in Go?

How to Read Environment Variables and Configuration in Go

In Go, reading environment variables and configuration is crucial for managing application settings. Environment variables are a way to pass configuration settings from the operating system to your application. To access these variables, you can use the `os` package.

Example of reading environment variables in Go

package main

import (
    "fmt"
    "os"
)

func main() {
    // Get the value of the environment variable
    greeting := os.Getenv("GREETING")

    if greeting == "" {
        greeting = "Hello, World!" // Fallback default value
    }

    fmt.Println(greeting)
}

This example demonstrates how to retrieve an environment variable named `GREETING`. If the variable is not set, it defaults to "Hello, World!". Make sure to set the environment variable in your system to see it in action.