bashexec

Documentation

Overview

Package bashexec provides helpers to execute bash code. What this primarily offers over directly writing e.g. `exec.Command("bash")` is:

• By default, all fragments are executed in "bash strict mode": http://redsymbol.net/articles/unofficial-bash-strict-mode/
• The code encourages adding a "name" for in-memory scripts, similar to e.g. Ansible tasks as well as many CI systems like Github actions
• The code to execute is piped to stdin instead of passed via `-c` which avoids argument length limits and makes the output of e.g. `ps` readable.
• Scripts are assumed synchronous, and stdin/stdout/stderr are passed directly instead of piped.
• We use prctl(PR_SET_PDEATHSIG) (assuming Linux) to lifecycle bind the script to the caller

Index

• Constants
• func Run(name, cmd string) error
• func RunA(cmd string) error
• type BashRunner
  • func NewBashRunner(name, src string, args ...string) (*BashRunner, error)
  • func (r *BashRunner) Exec() error
  • func (r *BashRunner) Run() error

Constants

const StrictMode = "set -euo pipefail"

StrictMode enables http://redsymbol.net/articles/unofficial-bash-strict-mode/

Functions

func Run

func Run(name, cmd string) error

Run spawns a named script (without any arguments), gathering stdout/stderr into a buffer that is displayed only on error.

func RunA

func RunA(cmd string) error

RunA spawns an anonymous script, and is otherwise the same as `Run`.

Types

type BashRunner

type BashRunner struct {
	// contains filtered or unexported fields
}

BashRunner is a wrapper for executing in-memory bash scripts

func NewBashRunner

func NewBashRunner(name, src string, args ...string) (*BashRunner, error)

NewBashRunner creates a bash executor from in-memory shell script.

func (*BashRunner) Exec

func (r *BashRunner) Exec() error

Exec synchronously spawns the child process, passing stdin/stdout/stderr directly.

func (*BashRunner) Run

func (r *BashRunner) Run() error

Run spawns the script, gathering stdout/stderr into a buffer that is displayed only on error.