forked from dgraph-io/ristretto
-
Notifications
You must be signed in to change notification settings - Fork 1
/
flags.go
300 lines (273 loc) · 6.6 KB
/
flags.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
package z
import (
"fmt"
"log"
"os"
"os/user"
"path/filepath"
"sort"
"strconv"
"strings"
"time"
)
// SuperFlagHelp makes it really easy to generate command line `--help` output for a SuperFlag. For
// example:
//
// const flagDefaults = `enabled=true; path=some/path;`
//
// var help string = z.NewSuperFlagHelp(flagDefaults).
// Flag("enabled", "Turns on <something>.").
// Flag("path", "The path to <something>.").
// Flag("another", "Not present in defaults, but still included.").
// String()
//
// The `help` string would then contain:
//
// enabled=true; Turns on <something>.
// path=some/path; The path to <something>.
// another=; Not present in defaults, but still included.
//
// All flags are sorted alphabetically for consistent `--help` output. Flags with default values are
// placed at the top, and everything else goes under.
type SuperFlagHelp struct {
defaults *SuperFlag
flags map[string]string
head string
}
func NewSuperFlagHelp(defaults string) *SuperFlagHelp {
return &SuperFlagHelp{
defaults: NewSuperFlag(defaults),
flags: make(map[string]string, 0),
}
}
func (h *SuperFlagHelp) Head(head string) *SuperFlagHelp {
h.head = head
return h
}
func (h *SuperFlagHelp) Flag(name, description string) *SuperFlagHelp {
h.flags[name] = description
return h
}
func (h *SuperFlagHelp) String() string {
defaultLines := make([]string, 0)
otherLines := make([]string, 0)
for name, help := range h.flags {
val, found := h.defaults.m[name]
line := fmt.Sprintf(" %s=%s; %s\n", name, val, help)
if found {
defaultLines = append(defaultLines, line)
} else {
otherLines = append(otherLines, line)
}
}
sort.Strings(defaultLines)
sort.Strings(otherLines)
dls := strings.Join(defaultLines, "")
ols := strings.Join(otherLines, "")
if len(h.defaults.m) == 0 && len(ols) == 0 {
// remove last newline
dls = dls[:len(dls)-1]
}
// remove last newline
if len(h.defaults.m) == 0 && len(ols) > 1 {
ols = ols[:len(ols)-1]
}
return h.head + "\n" + dls + ols
}
func parseFlag(flag string) (map[string]string, error) {
kvm := make(map[string]string)
for _, kv := range strings.Split(flag, ";") {
if strings.TrimSpace(kv) == "" {
continue
}
// For a non-empty separator, 0 < len(splits) ≤ 2.
splits := strings.SplitN(kv, "=", 2)
k := strings.TrimSpace(splits[0])
if len(splits) < 2 {
return nil, fmt.Errorf("superflag: missing value for '%s' in flag: %s", k, flag)
}
k = strings.ToLower(k)
k = strings.ReplaceAll(k, "_", "-")
kvm[k] = strings.TrimSpace(splits[1])
}
return kvm, nil
}
type SuperFlag struct {
m map[string]string
}
func NewSuperFlag(flag string) *SuperFlag {
sf, err := newSuperFlagImpl(flag)
if err != nil {
log.Fatal(err)
}
return sf
}
func newSuperFlagImpl(flag string) (*SuperFlag, error) {
m, err := parseFlag(flag)
if err != nil {
return nil, err
}
return &SuperFlag{m}, nil
}
func (sf *SuperFlag) String() string {
if sf == nil {
return ""
}
kvs := make([]string, 0, len(sf.m))
for k, v := range sf.m {
kvs = append(kvs, fmt.Sprintf("%s=%s", k, v))
}
return strings.Join(kvs, "; ")
}
func (sf *SuperFlag) MergeAndCheckDefault(flag string) *SuperFlag {
sf, err := sf.MergeWithDefault(flag)
if err != nil {
log.Fatal(err)
}
return sf
}
func (sf *SuperFlag) MergeWithDefault(flag string) (*SuperFlag, error) {
if sf == nil {
m, err := parseFlag(flag)
if err != nil {
return nil, err
}
return &SuperFlag{m}, nil
}
src, err := parseFlag(flag)
if err != nil {
return nil, err
}
numKeys := len(sf.m)
for k := range src {
if _, ok := sf.m[k]; ok {
numKeys--
}
}
if numKeys != 0 {
return nil, fmt.Errorf("superflag: found invalid options in flag: %s.\nvalid options: %v", sf, flag)
}
for k, v := range src {
if _, ok := sf.m[k]; !ok {
sf.m[k] = v
}
}
return sf, nil
}
func (sf *SuperFlag) Has(opt string) bool {
val := sf.GetString(opt)
return val != ""
}
func (sf *SuperFlag) GetDuration(opt string) time.Duration {
val := sf.GetString(opt)
if val == "" {
return time.Duration(0)
}
if strings.Contains(val, "d") {
val = strings.Replace(val, "d", "", 1)
days, err := strconv.ParseUint(val, 0, 64)
if err != nil {
return time.Duration(0)
}
return time.Hour * 24 * time.Duration(days)
}
d, err := time.ParseDuration(val)
if err != nil {
return time.Duration(0)
}
return d
}
func (sf *SuperFlag) GetBool(opt string) bool {
val := sf.GetString(opt)
if val == "" {
return false
}
b, err := strconv.ParseBool(val)
if err != nil {
log.Fatalf("unable to parse %s as bool for key: %s. Options: %s: %v",
val, opt, sf, err)
}
return b
}
func (sf *SuperFlag) GetFloat64(opt string) float64 {
val := sf.GetString(opt)
if val == "" {
return 0
}
f, err := strconv.ParseFloat(val, 64)
if err != nil {
log.Fatalf("unable to parse %s as float64 for key: %s. Options: %s: %v",
val, opt, sf, err)
}
return f
}
func (sf *SuperFlag) GetInt64(opt string) int64 {
val := sf.GetString(opt)
if val == "" {
return 0
}
i, err := strconv.ParseInt(val, 0, 64)
if err != nil {
log.Fatalf("unable to parse %s as int64 for key: %s. Options: %s: %v",
val, opt, sf, err)
}
return i
}
func (sf *SuperFlag) GetUint64(opt string) uint64 {
val := sf.GetString(opt)
if val == "" {
return 0
}
u, err := strconv.ParseUint(val, 0, 64)
if err != nil {
log.Fatalf("unable to parse %s as uint64 for key: %s. Options: %s: %v",
val, opt, sf, err)
}
return u
}
func (sf *SuperFlag) GetUint32(opt string) uint32 {
val := sf.GetString(opt)
if val == "" {
return 0
}
u, err := strconv.ParseUint(val, 0, 32)
if err != nil {
log.Fatalf("unable to parse %s as uint32 for key: %s. Options: %s: %v",
val, opt, sf, err)
}
return uint32(u)
}
func (sf *SuperFlag) GetString(opt string) string {
if sf == nil {
return ""
}
return sf.m[opt]
}
func (sf *SuperFlag) GetPath(opt string) string {
p := sf.GetString(opt)
path, err := expandPath(p)
if err != nil {
log.Fatalf("Failed to get path: %+v", err)
}
return path
}
// expandPath expands the paths containing ~ to /home/user. It also computes the absolute path
// from the relative paths. For example: ~/abc/../cef will be transformed to /home/user/cef.
func expandPath(path string) (string, error) {
if len(path) == 0 {
return "", nil
}
if path[0] == '~' && (len(path) == 1 || os.IsPathSeparator(path[1])) {
usr, err := user.Current()
if err != nil {
return "", fmt.Errorf("failed to get the home directory of the user: %w", err)
}
path = filepath.Join(usr.HomeDir, path[1:])
}
var err error
path, err = filepath.Abs(path)
if err != nil {
return "", fmt.Errorf("failed to generate absolute path: %w", err)
}
return path, nil
}