envr

README

envr

Check / set required env vars, optionally from a local .env file. Uses the godotenv by John Barton.

Purpose

A convenient way to set env vars with a local file, or defer to env vars already set by some other means, eg Heroku config.

Installation

$ go get github.com/34South/envr

Usage

Set up a new Envr and pass in the env vars your app expects to be set.

func init() {
	env := envr.New("myEnv", []string{
  		"SOME_VAR1",
  		"SOME_VAR2",
  		"SOME_APP_ID",
  		"SOME_API_KEY",
	}).Auto()
}

// Envr contains fields related to the environment vars 
type Envr struct {
	Ready        bool              `json:"ready"`           // Flag for the goodness
	Name         string            `json:"environmentName"` // name of environment
	Files        []string          `json:"configFiles"`     // files to read from, default .env
	RequiredVars []string          `json:"requiredVars"`    // the env vars we need
	ExistingVars []string          `json:"existingVars"`    // the env vars that are set
	MissingVars  []string          `json:"missingVars"`     // the env vars not set
	V            map[string]string `json:"values"`          // map of existing vars and values
	Status       string            `json:"status"`          // a message about current status
	Error        error             `json:"error"`           // error field, for easier method chaining
}

Envr Methods

.New("envName", []string{"var1", "var2"}, "configFile1, configFile2...")

• Initialises a new Envr value with (arbitrary) name "envName"
• Second argument is a []string containing names of all expected / required env vars
• Third argument is an optional list of files containing env var names and values. If not present defaults to .env.

The .env file can be formatted like this:

# Comments are allowed
VAR1="value one"
VAR2=1234

See godotenv for details.

Methods

.Auto() Quick way to do .Clean.Fatal() - sets all the expected vars found in .env, and exists if any are missing.

.Passive() Set expected vars ONLY if they are NOT already set.

.Clean() Set all expected vars without checking first.

.Fatal() Exits if the environment is NOT .Ready = true

Todo

• Check vars that exist in config but are MISSING in the expectations list
• Learn how to write tests
• Write tests
• Go sailing

License

The MIT License (MIT) Copyright © 2017 Mike Donnici

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Documentation

Index

• type Envr
  • func New(n string, vs []string, f ...string) *Envr
  • func (e *Envr) Auto() *Envr
  • func (e *Envr) Clean() *Envr
  • func (e *Envr) Fatal() *Envr
  • func (e *Envr) IsSet(v string) bool
  • func (e *Envr) Passive() *Envr
  • func (e *Envr) SetList(lv []string, ev map[string]string) *Envr
  • func (e *Envr) SetVar(v, s string) error
  • func (e *Envr) Update()

Types

type Envr

type Envr struct {
	Ready        bool              `json:"ready"`           // Flag for the goodness
	Name         string            `json:"environmentName"` // name of environment
	Files        []string          `json:"configFiles"`     // files to read from, default .env
	RequiredVars []string          `json:"requiredVars"`    // the env vars we need
	ExistingVars []string          `json:"existingVars"`    // the env vars that are set
	MissingVars  []string          `json:"missingVars"`     // the env vars not set
	V            map[string]string `json:"values"`          // map of existing vars and values
	Status       string            `json:"status"`          // a message about current statuss
	Error        error             `json:"error"`           // error field, for easier method chaining
}

Envr contains info about the environment setup

func New

func New(n string, vs []string, f ...string) *Envr

New sets up a new Environment. It takes an arbitrary name (n), a list of required vars (vs) and zero or more file names from which to read the vars, eg ".env1,.env2". Defaults to .env

func (*Envr) Auto

func (e *Envr) Auto() *Envr

Auto does Clean().Fatal() so will force the setting of all the required vars from the config, and die if things didn't workout

func (*Envr) Clean

func (e *Envr) Clean() *Envr

Clean sets every var present in the confg without checking if they exist

func (*Envr) Fatal

func (e *Envr) Fatal() *Envr

Fatal is chained on so we can log fatal in the event our environment is not set up properly

func (*Envr) IsSet

func (e *Envr) IsSet(v string) bool

IsSet checks if a var is currently set

func (*Envr) Passive

func (e *Envr) Passive() *Envr

Passive checks if vars are already set, and only sets them if they are not.

func (*Envr) SetList

func (e *Envr) SetList(lv []string, ev map[string]string) *Envr

SetList just sets a list of env vars passed in to 'lv'. Also need to pass in the config vars map 'ev' so we can check there is a value there before we try to set it.

func (*Envr) SetVar

func (e *Envr) SetVar(v, s string) error

SetVar sets env var 'v' to value 's', if successful it updates Envr

func (*Envr) Update

func (e *Envr) Update()

Update sets / updates fields in the Envr value