Playing with Environment Variables in Golang

Introduction

Hi, in this session we will learn how to read variable keys from .env file into our code, or we use to call it by handling environment variables in Golang.

Hands On

This will be a very quick tutorial, so let's just start it by initializing the project modules.

go mod init {your package name}

Then get and download specific dependencies from package github.com/joho/godotenv

go get github.com/joho/godotenv
go mod vendor

Let's headed to the root directories of the project and created the file call .env with contents of

HELLO=from the other side

and run our main script in main.go

package main

import (
    "fmt"
    "log"
    "os"

    "github.com/joho/godotenv"
)

func init() {
    err := godotenv.Load(".env")
    if err != nil {
        log.Fatal("Error loading .env file")
    }
}

func main() {
    fmt.Printf("%s", os.Getenv("HELLO"))
}

Or if we do not want to mix things up with os.GetEnv, we can just also use it like this

package main

import (
    "fmt"
    "log"

    "github.com/joho/godotenv"
)

func main() {
    var envs map[string]string
    envs, err := godotenv.Read(".env")

    if err != nil {
        log.Fatal("Error loading .env file")
    }

    hello := envs["HELLO"]

    fmt.Printf("%s", hello)
}

this will have the same results

Conclusion

Allright, this is it for a quick tutorial, Happy exploring!

Source

• https://zetcode.com/golang/env/
• https://github.com/joho/godotenv