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
|
---
tags:
- v1
---
The default help flag (`-h/--help`) is defined as `cli.HelpFlag` and is checked
by the cli internals in order to print generated help text for the app, command,
or subcommand, and break execution.
#### Customization
All of the help text generation may be customized, and at multiple levels. The
templates are exposed as variables `AppHelpTemplate`, `CommandHelpTemplate`, and
`SubcommandHelpTemplate` which may be reassigned or augmented, and full override
is possible by assigning a compatible func to the `cli.HelpPrinter` variable,
e.g.:
<!-- {
"output": "Ha HA. I pwnd the help!!1"
} -->
``` go
package main
import (
"fmt"
"log"
"io"
"os"
"github.com/urfave/cli"
)
func main() {
// EXAMPLE: Append to an existing template
cli.AppHelpTemplate = fmt.Sprintf(`%s
WEBSITE: http://awesometown.example.com
SUPPORT: support@awesometown.example.com
`, cli.AppHelpTemplate)
// EXAMPLE: Override a template
cli.AppHelpTemplate = `NAME:
{{.Name}} - {{.Usage}}
USAGE:
{{.HelpName}} {{if .VisibleFlags}}[global options]{{end}}{{if .Commands}} command [command options]{{end}} {{if .ArgsUsage}}{{.ArgsUsage}}{{else}}[arguments...]{{end}}
{{if len .Authors}}
AUTHOR:
{{range .Authors}}{{ . }}{{end}}
{{end}}{{if .Commands}}
COMMANDS:
{{range .Commands}}{{if not .HideHelp}} {{join .Names ", "}}{{ "\t"}}{{.Usage}}{{ "\n" }}{{end}}{{end}}{{end}}{{if .VisibleFlags}}
GLOBAL OPTIONS:
{{range .VisibleFlags}}{{.}}
{{end}}{{end}}{{if .Copyright }}
COPYRIGHT:
{{.Copyright}}
{{end}}{{if .Version}}
VERSION:
{{.Version}}
{{end}}
`
// EXAMPLE: Replace the `HelpPrinter` func
cli.HelpPrinter = func(w io.Writer, templ string, data interface{}) {
fmt.Println("Ha HA. I pwnd the help!!1")
}
err := cli.NewApp().Run(os.Args)
if err != nil {
log.Fatal(err)
}
}
```
The default flag may be customized to something other than `-h/--help` by
setting `cli.HelpFlag`, e.g.:
<!-- {
"args": ["--halp"],
"output": "haaaaalp.*HALP"
} -->
``` go
package main
import (
"log"
"os"
"github.com/urfave/cli"
)
func main() {
cli.HelpFlag = cli.BoolFlag{
Name: "halp, haaaaalp",
Usage: "HALP",
EnvVar: "SHOW_HALP,HALPPLZ",
}
err := cli.NewApp().Run(os.Args)
if err != nil {
log.Fatal(err)
}
}
```
|
