forked from joho/godotenv
/
godotenv.go
301 lines (261 loc) · 7.59 KB
/
godotenv.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
// 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"
"regexp"
"path/filepath"
)
// 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) {
if importFile := parseImport(fullLine); importFile != "" {
// load import relative to location of current file
err := loadNestedEnv(envMap, importFile, filename)
if err != nil {
return envMap, err
}
}
} else if source := parseSource(fullLine); source != "" {
source = removeComments(source)
err := loadNestedEnv(envMap, source, filename)
if err != nil {
return envMap, err
}
} else {
key, value, err := parseLine(fullLine)
if err == nil {
envMap[key] = value
}
}
}
return
}
func pathToImport(importPath, sourceFile string) (string, error) {
if filepath.IsAbs(importPath) {
return importPath, nil
}
var absFileName string
absFileName, err := filepath.Abs(sourceFile)
if err != nil {
// bail here. Since we already opened the parent env file, Abs() should have
// worked
return "", err
}
fileDir := filepath.Dir(absFileName)
return filepath.Join(fileDir, importPath), nil
}
func loadNestedEnv(parent map[string]string, nestedFileName, parentFileName string) error {
var err error
nestedFileName, err = pathToImport(nestedFileName, parentFileName)
if err != nil {
return err
}
nested, err := readFile(nestedFileName)
if err == nil {
// merge the nested map into the parent
for key, value := range nested {
parent[key] = value
}
} else if !os.IsNotExist(err) {
// ignore file not found errors. imported files are ignored if not present
return err
}
return nil
}
func parseLine(line string) (key string, value string, err error) {
if len(line) == 0 {
err = errors.New("zero length string")
return
}
line = removeComments(line)
// 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, "#")
}
func removeComments(line string) string {
// 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, "#")
}
return line
}
func parseImport(line string) string {
submatches := regexp.MustCompile(`(?m)^#\s*import:(.*)$`).FindStringSubmatch(line)
if len(submatches) < 2 {
return ""
}
return strings.Trim(submatches[1], " \n\t")
}
func parseSource(line string) string {
submatches := regexp.MustCompile(`(?m)^(\.|source) \s*(.*)$`).FindStringSubmatch(line)
if len(submatches) < 3 {
return ""
}
return strings.Trim(submatches[2], " \n\t")
}