drone-docker-buildx/vendor/github.com/joho/godotenv/godotenv.go
2016-05-03 16:17:16 -07:00

230 lines
5.7 KiB
Go

// 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 avaiable through os.Getenv("SOME_ENV_VAR")
package godotenv
import (
"bufio"
"errors"
"os"
"os/exec"
"strings"
)
// 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 Load(filenames ...string) (err error) {
filenames = filenamesOrDefault(filenames)
for _, filename := range filenames {
err = loadFile(filename, false)
if err != nil {
return // return early on a spazout
}
}
return
}
// 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 forcefilly set all vars.
func Overload(filenames ...string) (err error) {
filenames = filenamesOrDefault(filenames)
for _, filename := range filenames {
err = loadFile(filename, true)
if err != nil {
return // return early on a spazout
}
}
return
}
// Read all env (with same file loading semantics as Load) but return values as
// a map rather than automatically writing values into env
func Read(filenames ...string) (envMap map[string]string, err error) {
filenames = filenamesOrDefault(filenames)
envMap = make(map[string]string)
for _, filename := range filenames {
individualEnvMap, individualErr := readFile(filename)
if individualErr != nil {
err = individualErr
return // return early on a spazout
}
for key, value := range individualEnvMap {
envMap[key] = value
}
}
return
}
// 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 Exec(filenames []string, cmd string, cmdArgs []string) error {
Load(filenames...)
command := exec.Command(cmd, cmdArgs...)
command.Stdin = os.Stdin
command.Stdout = os.Stdout
command.Stderr = os.Stderr
return command.Run()
}
func filenamesOrDefault(filenames []string) []string {
if len(filenames) == 0 {
return []string{".env"}
}
return filenames
}
func loadFile(filename string, overload bool) error {
envMap, err := readFile(filename)
if err != nil {
return err
}
for key, value := range envMap {
if os.Getenv(key) == "" || overload {
os.Setenv(key, value)
}
}
return nil
}
func readFile(filename string) (envMap map[string]string, err error) {
file, err := os.Open(filename)
if err != nil {
return
}
defer file.Close()
envMap = make(map[string]string)
var lines []string
scanner := bufio.NewScanner(file)
for scanner.Scan() {
lines = append(lines, scanner.Text())
}
for _, fullLine := range lines {
if !isIgnoredLine(fullLine) {
key, value, err := parseLine(fullLine)
if err == nil {
envMap[key] = value
}
}
}
return
}
func parseLine(line string) (key string, value string, err error) {
if len(line) == 0 {
err = errors.New("zero length string")
return
}
// ditch the comments (but keep quoted hashes)
if strings.Contains(line, "#") {
segmentsBetweenHashes := strings.Split(line, "#")
quotesAreOpen := false
var segmentsToKeep []string
for _, segment := range segmentsBetweenHashes {
if strings.Count(segment, "\"") == 1 || strings.Count(segment, "'") == 1 {
if quotesAreOpen {
quotesAreOpen = false
segmentsToKeep = append(segmentsToKeep, segment)
} else {
quotesAreOpen = true
}
}
if len(segmentsToKeep) == 0 || quotesAreOpen {
segmentsToKeep = append(segmentsToKeep, segment)
}
}
line = strings.Join(segmentsToKeep, "#")
}
// now split key from value
splitString := strings.SplitN(line, "=", 2)
if len(splitString) != 2 {
// try yaml mode!
splitString = strings.SplitN(line, ":", 2)
}
if len(splitString) != 2 {
err = errors.New("Can't separate key from value")
return
}
// Parse the key
key = splitString[0]
if strings.HasPrefix(key, "export") {
key = strings.TrimPrefix(key, "export")
}
key = strings.Trim(key, " ")
// Parse the value
value = splitString[1]
// trim
value = strings.Trim(value, " ")
// check if we've got quoted values
if strings.Count(value, "\"") == 2 || strings.Count(value, "'") == 2 {
// pull the quotes off the edges
value = strings.Trim(value, "\"'")
// expand quotes
value = strings.Replace(value, "\\\"", "\"", -1)
// expand newlines
value = strings.Replace(value, "\\n", "\n", -1)
}
return
}
func isIgnoredLine(line string) bool {
trimmedLine := strings.Trim(line, " \n\t")
return len(trimmedLine) == 0 || strings.HasPrefix(trimmedLine, "#")
}