terminal

Documentation

Overview

Package terminal implements the functions for all terminal interactions in the frontend. These includes to get a shell into a Pod, SSH sessions for a Node and the streaming of log files. The implementation is very similar to the implementation in the "Kubernetes Dashboard", you can find the file here: https://github.com/kubernetes/dashboard/blob/master/src/app/backend/handler/terminal.go

Index

• Constants
• func IsValidShell(shell string) bool
• func StartProcess(config *rest.Config, reqURL *url.URL, cmd []string, ptyHandler PtyHandler) error
• type Message
• type PtyHandler
• type Session
  • func (t Session) Next() *remotecommand.TerminalSize
  • func (t Session) Read(p []byte) (int, error)
  • func (t Session) Write(p []byte) (int, error)

Constants

const END_OF_TRANSMISSION = "\u0004"

Functions

func IsValidShell

func IsValidShell(shell string) bool

IsValidShell checks if the user provided shell is an allowed one.

func StartProcess

func StartProcess(config *rest.Config, reqURL *url.URL, cmd []string, ptyHandler PtyHandler) error

StartProcess executes the given command (cmd) in the container specified in the request and connects it up with the ptyHandler (a session).

Types

type Message

type Message struct {
	Op, Data   string
	Rows, Cols uint16
}

Message is the messaging protocol between the shell and terminal session.

OP DIRECTION FIELD(S) USED DESCRIPTION --------------------------------------------------------------------- stdin fe->be Data Keystrokes/paste buffer resize fe->be Rows, Cols New terminal size stdout be->fe Data Output from the process

type PtyHandler

type PtyHandler interface {
	io.Reader
	io.Writer
	remotecommand.TerminalSizeQueue
}

PtyHandler is what remotecommand expects from a pty.

type Session

type Session struct {
	WebSocket *websocket.Conn
	SizeChan  chan remotecommand.TerminalSize
	DoneChan  chan struct{}
}

Session implements PtyHandler (using a WebSocket connection).

func (Session) Next

func (t Session) Next() *remotecommand.TerminalSize

Next is called in a loop from remotecommand as long as the process is running. TerminalSize handles pty->process resize events.

func (Session) Read

func (t Session) Read(p []byte) (int, error)

Read handles pty->process messages (stdin, resize). Called in a loop from remotecommand as long as the process is running.

func (Session) Write

func (t Session) Write(p []byte) (int, error)

Write handles process->pty stdout. Called from remotecommand whenever there is any output.