mgenware / j9

Shell scripting, SSH in Go

j9

Shell scripting, SSH in Go.

Installation

go get github.com/mgenware/j9/v2

Examples

Check if tree command is available and install it if necessary. (Assuming on macOS with homebrew installed):

package main

import (
	"fmt"
	"os/exec"

	"github.com/mgenware/j9/v2"
)

func main() {
	// Local node runs on your local system.
	// `ConsoleLogger` prints logs to the current console.
	t := j9.NewTunnel(j9.NewLocalNode(), j9.NewConsoleLogger())

	// Check if the command `tree` is installed.
	_, err := exec.LookPath("tree")
	if err != nil {
		t.Logger().Log(j9.LogLevelError, "tree is not installed")
		t.Run("brew", "install", "tree")
	}
	fmt.Println("tree is installed")
	t.Run("tree", ".")
}

Sample output when tree is not installed:

❯ go run main.go
tree is not installed
brew install tree
==> Downloading https://homebrew.bintray.com/bottles/tree-1.7.0.high_sierra.bottle.1.tar.gz
==> Pouring tree-1.7.0.high_sierra.bottle.1.tar.gz
🍺  /usr/local/Cellar/tree/1.7.0: 8 files, 114.3KB
tree is installed
tree .
.
└── main.go

0 directories, 1 file

SSH with a private key

package main

import (
	"github.com/mgenware/j9/v2"
)

func main() {
	config := &j9.SSHConfig{
		Host: "1.2.3.4",
		User: "root",
		Auth: j9.MustCreateKeyBasedAuth("~/key.pem"),
	}

	t := j9.NewTunnel(j9.MustCreateSSHNode(config), j9.NewConsoleLogger())
	t.RunSync("pwd")
	t.RunSync("ls")
}

Sample output:

pwd
/root

ls
bin
build
data

Windows Support

Use WSL 2.

Run vs RunSync

First, they have different function signatures:

// Run runs the given command, returns an error if the command fails.
Run(name string, arg ...string) error

// RunSync runs the given command, returns the output and an error if the command fails.
RunSync(cmd string) ([]byte, error)

Use them based on your use cases.

	Run	RunSync
Return stdout and stderr as a string	❌	✅
Live process output (good for long-running processes)	✅	❌
Supported in LocalNode	✅	✅
Supported in SSHNode	❌	✅