README
¶
skapt
Lightweight package for building command line apps in Go
I was inspired from other command line libraries to do my own package in Go.
API example
Example of command line with two arguments. One flag is required to be explicitly passed.
All the code in this example is written in one main.go file.
package main
import (
"fmt"
"os"
"time"
"github.com/hoenirvili/skapt"
"github.com/hoenirvili/skapt/argument"
"github.com/hoenirvili/skapt/flag"
)
func main() {
app := skapt.Application{
Name: "Example",
Description: "Example is an example of command line app",
Version: "1.0.0",
Handler: func(ctx *skapt.Context) error {
w := ctx.Int("wait")
wait := time.Duration(w)
exp := ctx.String("e")
time.Sleep(wait * time.Second)
_, err := fmt.Fprintf(ctx.Stdout, exp)
return err
},
Flags: flag.Flags{{
Short: "e", Long: "exp",
Description: "Print something funny",
Type: argument.String,
Required: true,
}, {
Short: "w", Long: "wait",
Description: "How many seconds to wait until you print",
Type: argument.Int,
}},
}
app.Exec(os.Args)
}
If we try to pass a long argument --help than we get this auto-generated output.
By default we append help and version flags if the Flags slice does not contain any of them.
Help output
$ : main --help
Usage: Example [OPTIONS] [ARG...]
Example [ --help | -h | -v | --version ]
Example is an example of command line app
Options:
-e --exp Print something funny
-w --wait How many seconds to wait until you print
-h --help Print out the help menu
-v --version Print out the version of the program
For the version flag.
Version output
$ : main -v
Version 1.0.0
$ : main --version
Version 1.0.0
In our Application struct we declared 2 flags, -e/--exp and -w/--wait,
if we pass valid values, the program sleeps 3 seconds and outputs the message passed in -e.
Run output
$ : main -e "Example text" --wait=3
Example text
Error output
We treat all basic errors by default.
$ : main
Option -e --exp is required
This also checks if the value passed is valid.
$ : main -w fjsuiajfsd
Cannot parse value "fjsiadufj" as int
FAQ
-
Why should I use this package instead of a more popular one?
Really, nothing is stopping you to use one that is more battle tested, a more matured package.
The reason for developing another command line parsing package was that I often want to write
a simple lightweight command line app and I don't need more features than some basic flag value checking
and a simpler flag value retrieval api. -
Why not standard lib one?
I didn't like the interface they provided and their flag value retrieval.
Documentation
¶
Overview ¶
Package skapt provides a tiny interface to create and manage your command line applications
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Application ¶
type Application struct {
// Name of the command line application
Name string
// Usage is the usage of the command line
Usage string
// Description holds the description of the command line
Description string
// Version is the version of the application
Version string
// Flags holds list of the root command
Flags flag.Flags
// NArgs minim required value args
NArgs int
// Handler is the root main handler
Handler func(ctx *Context) error
// Stdout place to write information that the user
// needs to know
Stdout io.Writer
// Stderr place where all error messages should be written
Stderr io.Writer
}
Application will hold all the information for creating and parsing the command line
func (Application) Exec ¶
func (a Application) Exec(args []string) (err error)
Exec executes the command line based on the args provided
type Context ¶
type Context struct {
// Flags contains the parsed flags
flag.Flags
// Args additional command line arguments
Args []string
// Stdout writer to stdout
Stdout io.Writer
// Stdout writer to stderr
Stderr io.Writer
}
Context holds context specific information for the current running handler
Source Files
Directories
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| Path | Synopsis |
|---|---|
|
Package argument provides small set of types to parse and interpret command line arguments Package argument provides small set of types to parse and interpret command line arguments
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Package argument provides small set of types to parse and interpret command line arguments Package argument provides small set of types to parse and interpret command line arguments |
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Package flag provides types and functions to create and manage your command line applications Package flag provides types and functions to create and manage your command line applications
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Package flag provides types and functions to create and manage your command line applications Package flag provides types and functions to create and manage your command line applications |