Substitute Environment Variables (subenv)

This package was developed to simplify the usage of environmental variables, mainly when working with containers. I personally do not like using config files and prefer my apps not to be dependent on any external configurations to be able to function.

Use case

Instead of hard-coding variables into your application or configuration files, simply use this library to read the required configuration from environment variable! If there is no variable present, a default value can be also set. In some cases, you might wish to override a variable, this can be done by using the Override(key, value) function.

Common uses

1. Setting application listening port.
2. Changing database host address and listening port.
3. Any other value that should have the ability to be changed.

Installation

go get github.com/Entrio/subenv

Example

package main

import (
	"github.com/Entrio/subenv"
	"github.com/labstack/echo/v4"
)

func main() {
	e := echo.New()
	e.GET("/", func(c echo.Context) error {
		return c.String(200, "Hello, world")
	})
	e.Logger.Fatal(e.Start(subenv.Env("LISTEN_ENDPOINT", ":1234")))
}

Available functions

Env(string key,default value) string - Get the string equivalent of key. Default value will be returned if the key is null or not present.

EnvI(string key,default value) int - Get the int equivalent of the key. Default value will be returned if the key is null or non present

EnvB(string key,default value) bool - Get the bool equivalent of the key. Default value will be returned if the key is null or non present

Override(key string, value interface{}) - Override any values that might be fetched. This is usually great for testing. This should be used right at the start of application launch.