easyexec is a simple wrapper around the built-in os/exec library. While it's very flexible, I don't find the interface to os/exec to be friendly enough, so I made this small library to make running external commands in Go simple.
This has 0 dependencies on third-party libraries! Only libraries built into the core Go library are used.
go get github.com/dorenproctor/easyexec
// Wrapper for exec.Cmd that outputs Stdout, Stderr, and Error in a struct
func Run(command string, arg ...string) Output
// Wrapper for exec.Cmd that streams stdout, stderr, and error and outputs them in a struct
// Defaults are Stdout/Stderr pipes and not surrounding streamed stderr in red ANSI.
// If o is nil, defaults are used
func RunStream(o *Options, command string, arg ...string) Output
type Output struct {
Err error
Stderr string
Stdout string
}
// Options for RunStream()
type Options struct {
// If nil, defaults to fmt.Print(s)
PrintOut func(s string)
// If nil, defaults to fmt.Fprint(os.Stderr, s)
PrintErr func(s string)
// If true, wrap text printed to StreamErr in red ANSI
StreamErrRed bool
}package yours
import (
"fmt"
"strings"
"github.com/dorenproctor/easyexec"
)
// Use the diff command built into the shell to compare 2 files or dirs
func Diff(src, dst string) error {
o := easyexec.Run("diff", src, dst)
s := o.Stdout + o.Stderr
if s == "" {
return nil
}
return fmt.Errorf(s)
}
func RunMyLongScript() error {
// prints to the console in real time but also stores it in output
o := easyexec.RunStream(nil, "python", "long_running_script.py")
if o.Err != nil {
return o.Err
}
// this (nonexistent) example script only ever prints to stdout
// and sometimes returns successfully but prints FAIL in its output
if strings.Contains(o.Stdout, "FAIL") {
return fmt.Errorf("command failed: %s", o.Stdout)
}
return nil
}
func RunStreamWithStderrPrintedInRed() error {
// prints to the console in real time but also stores it in output
return easyexec.RunStream(
&easyexec.Options{StreamErrRed: true},
"bash",
"my_script.sh",
"--a-flag",
"some",
"args",
).Err
}