runcmd

README

go-runcmd

go-runcmd is a Go library and common interface for running local and remote commands providing the Runner interface which helps to abstract away running local and remote shell commands

Borrowed from kovetskiy/runcmd-

Install

go get github.com/aucloud/go-runcmd

Usage

First, import the library:

import "github.com/aucloud/go-runcmd"

Next, create a runner: this is a type, that holds:

• for local commands: empty struct
• for remote commands: connecttion to a remote host; so, you can create only one remote runner to remote host

Local Runner:

runner, err := runcmd.NewLocalRunner()
if err != nil {
  //handle error
}

Remote Runner:

runner, err := runcmd.NewRemoteKeyAuthRunner(
  "user",
  "127.0.0.1:22",
  "/home/user/id_rsa",
)
if err != nil {
  //handle error
}

After that, create a command, and call .Run():

c, err := runner.Command("date")
if err != nil {
  //handle error
}
out, err := c.Run()
if err != nil {
  //handle error
}

Both local and remote runners implements the Runner interface, so, you can work with them as Runner:

func listSomeDir(r Runner) error {
  c, err := r.Command("ls -la")
  if err != nil {
    //handle error
  }
  out, err := c.Run()
  if err != nil {
    //handle error
  }
  for _, i := range out {
    fmt.Println(i)
  }
}

Another useful code snippet: pipe from local to remote command:

lRunner, err := NewLocalRunner()
if err != nil {
  //handle error
}

rRunner, err := NewRemoteKeyAuthRunner(user, host, key)
if err != nil {
  //handle error
}

cLocal, err := lRunner.Command("date")
if err != nil {
  //handle error
}
if err = cmdLocal.Start(); err != nil {
  //handle error
}
cRemote, err := rRunner.Command("tee /tmp/tmpfile")
if err != nil {
  //handle error
}
if err = cRemote.Start(); err != nil {
  //handle error
}
if _, err = io.Copy(cRemote.StdinPipe(),cLocal.StdoutPipe(),); err != nil {
  //handle error
}

// Correct handle end of copying:
cmdLocal.Wait()
cmdRemote.StdinPipe().Close()
cmdRemote.Wait()

License

go-runcmd is licensed under the terms of the AGPLv3

Documentation

Index

• func ResolveHostname(hostport string) (net.Addr, error)
• type CmdWorker
• type ExecError
  • func (err ExecError) Error() string
• type Local
  • func NewLocalRunner() (*Local, error)
  • func (runner *Local) Command(cmdline string) (CmdWorker, error)
• type LocalCmd
  • func (cmd *LocalCmd) GetCommandLine() string
  • func (cmd *LocalCmd) Run() ([]string, error)
  • func (cmd *LocalCmd) SetStderr(buffer io.Writer)
  • func (cmd *LocalCmd) SetStdout(buffer io.Writer)
  • func (cmd *LocalCmd) Start() error
  • func (cmd *LocalCmd) StderrPipe() (io.Reader, error)
  • func (cmd *LocalCmd) StdinPipe() (io.WriteCloser, error)
  • func (cmd *LocalCmd) StdoutPipe() (io.Reader, error)
  • func (cmd *LocalCmd) Wait() error
• type Remote
  • func NewRemoteKeyAuthRunner(ctx context.Context, user, host, key string) (*Remote, error)
  • func NewRemoteKeyAuthRunnerViaJumphost(ctx context.Context, user, host, jumphost, key string) (*Remote, error)
  • func NewRemotePassAuthRunner(ctx context.Context, user, host, password string) (*Remote, error)
  • func (runner *Remote) CloseConnection() error
  • func (runner *Remote) Command(cmdline string) (CmdWorker, error)
• type RemoteCmd
  • func (cmd *RemoteCmd) GetCommandLine() string
  • func (cmd *RemoteCmd) Run() ([]string, error)
  • func (cmd *RemoteCmd) SetStderr(buffer io.Writer)
  • func (cmd *RemoteCmd) SetStdout(buffer io.Writer)
  • func (cmd *RemoteCmd) Start() error
  • func (cmd *RemoteCmd) StderrPipe() (io.Reader, error)
  • func (cmd *RemoteCmd) StdinPipe() (io.WriteCloser, error)
  • func (cmd *RemoteCmd) StdoutPipe() (io.Reader, error)
  • func (cmd *RemoteCmd) Wait() error
• type Runner

Functions

func ResolveHostname

func ResolveHostname(hostport string) (net.Addr, error)

Types

type CmdWorker

type CmdWorker interface {
	Run() ([]string, error)
	Start() error
	Wait() error
	StdinPipe() (io.WriteCloser, error)
	StdoutPipe() (io.Reader, error)
	StderrPipe() (io.Reader, error)
	SetStdout(buffer io.Writer)
	SetStderr(buffer io.Writer)
	GetCommandLine() string
}

type ExecError

type ExecError struct {
	ExecutionError error
	CommandLine    string
	Output         []string
}

func (ExecError) Error

func (err ExecError) Error() string

type Local

type Local struct{}

func NewLocalRunner

func NewLocalRunner() (*Local, error)

func (*Local) Command

func (runner *Local) Command(cmdline string) (CmdWorker, error)

type LocalCmd

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

func (*LocalCmd) GetCommandLine

func (cmd *LocalCmd) GetCommandLine() string

func (*LocalCmd) Run

func (cmd *LocalCmd) Run() ([]string, error)

func (*LocalCmd) SetStderr

func (cmd *LocalCmd) SetStderr(buffer io.Writer)

func (*LocalCmd) SetStdout

func (cmd *LocalCmd) SetStdout(buffer io.Writer)

func (*LocalCmd) Start

func (cmd *LocalCmd) Start() error

func (*LocalCmd) StderrPipe

func (cmd *LocalCmd) StderrPipe() (io.Reader, error)

func (*LocalCmd) StdinPipe

func (cmd *LocalCmd) StdinPipe() (io.WriteCloser, error)

func (*LocalCmd) StdoutPipe

func (cmd *LocalCmd) StdoutPipe() (io.Reader, error)

func (*LocalCmd) Wait

func (cmd *LocalCmd) Wait() error

type Remote

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

func NewRemoteKeyAuthRunner

func NewRemoteKeyAuthRunner(ctx context.Context, user, host, key string) (*Remote, error)

func NewRemoteKeyAuthRunnerViaJumphost

func NewRemoteKeyAuthRunnerViaJumphost(ctx context.Context, user, host, jumphost, key string) (*Remote, error)

func NewRemotePassAuthRunner

func NewRemotePassAuthRunner(ctx context.Context, user, host, password string) (*Remote, error)

func (*Remote) CloseConnection

func (runner *Remote) CloseConnection() error

func (*Remote) Command

func (runner *Remote) Command(cmdline string) (CmdWorker, error)

type RemoteCmd

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

func (*RemoteCmd) GetCommandLine

func (cmd *RemoteCmd) GetCommandLine() string

func (*RemoteCmd) Run

func (cmd *RemoteCmd) Run() ([]string, error)

func (*RemoteCmd) SetStderr

func (cmd *RemoteCmd) SetStderr(buffer io.Writer)

func (*RemoteCmd) SetStdout

func (cmd *RemoteCmd) SetStdout(buffer io.Writer)

func (*RemoteCmd) Start

func (cmd *RemoteCmd) Start() error

func (*RemoteCmd) StderrPipe

func (cmd *RemoteCmd) StderrPipe() (io.Reader, error)

func (*RemoteCmd) StdinPipe

func (cmd *RemoteCmd) StdinPipe() (io.WriteCloser, error)

func (*RemoteCmd) StdoutPipe

func (cmd *RemoteCmd) StdoutPipe() (io.Reader, error)

func (*RemoteCmd) Wait

func (cmd *RemoteCmd) Wait() error

type Runner

type Runner interface {
	Command(cmd string) (CmdWorker, error)
}