godotenv

README

Installation

As a library

go get github.com/lpernett/godotenv

or if you want to use it as a bin command

go >= 1.17

go install github.com/lpernett/godotenv/cmd/godotenv@latest

go < 1.17

go get github.com/lpernett/godotenv/cmd/godotenv

Usage

Add your application configuration to your .env file in the root of your project:

S3_BUCKET=YOURS3BUCKET
SECRET_KEY=YOURSECRETKEYGOESHERE

Then in your Go app you can do something like

package main

import (
    "log"
    "os"

    "github.com/lpernett/godotenv"
)

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

  s3Bucket := os.Getenv("S3_BUCKET")
  secretKey := os.Getenv("SECRET_KEY")

  // now do something with s3 or whatever
}

Documentation

Overview

Package godotenv is a go port of the ruby dotenv library (https://github.com/bkeepers/dotenv)

Examples/readme can be found on the GitHub page at https://github.com/joho/godotenv

The TL;DR is that you make a .env file that looks something like

SOME_ENV_VAR=somevalue

and then in your go code you can call

godotenv.Load()

and all the env vars declared in .env will be available through os.Getenv("SOME_ENV_VAR")

Index

• func Exec(filenames []string, cmd string, cmdArgs []string) error
• func Load(filenames ...string) (err error)
• func Marshal(envMap map[string]string) (string, error)
• func Overload(filenames ...string) (err error)
• func Parse(r io.Reader) (envMap map[string]string, err error)
• func Read(filenames ...string) (envMap map[string]string, err error)
• func Unmarshal(str string) (envMap map[string]string, err error)
• func Write(envMap map[string]string, filename string) error

Functions

func Exec

func Exec(filenames []string, cmd string, cmdArgs []string) error

Exec loads env vars from the specified filenames (empty map falls back to default) then executes the cmd specified.

Simply hooks up os.Stdin/err/out to the command and calls Run().

If you want more fine grained control over your command it's recommended that you use `Load()` or `Read()` and the `os/exec` package yourself.

func Load

func Load(filenames ...string) (err error)

Load will read your env file(s) and load them into ENV for this process.

Call this function as close as possible to the start of your program (ideally in main).

If you call Load without any args it will default to loading .env in the current path.

You can otherwise tell it which files to load (there can be more than one) like:

godotenv.Load("fileone", "filetwo")

It's important to note that it WILL NOT OVERRIDE an env variable that already exists - consider the .env file to set dev vars or sensible defaults.

func Marshal

func Marshal(envMap map[string]string) (string, error)

Marshal outputs the given environment as a dotenv-formatted environment file. Each line is in the format: KEY="VALUE" where VALUE is backslash-escaped.

func Overload

func Overload(filenames ...string) (err error)

Overload will read your env file(s) and load them into ENV for this process.

Call this function as close as possible to the start of your program (ideally in main).

If you call Overload without any args it will default to loading .env in the current path.

You can otherwise tell it which files to load (there can be more than one) like:

godotenv.Overload("fileone", "filetwo")

It's important to note this WILL OVERRIDE an env variable that already exists - consider the .env file to forcefully set all vars.

func Parse

func Parse(r io.Reader) (envMap map[string]string, err error)

Parse reads an env file from io.Reader, returning a map of keys and values.

func Read

func Read(filenames ...string) (envMap map[string]string, err error)

Read all env (with same file loading semantics as Load) but return values as a map rather than automatically writing values into env

func Unmarshal

func Unmarshal(str string) (envMap map[string]string, err error)

Unmarshal reads an env file from a string, returning a map of keys and values.

func Write

func Write(envMap map[string]string, filename string) error

Write serializes the given environment and writes it to a file.