wsl

Documentation

Overview

Package wsl enrolls the Windows Subsystem for Linux distro that runs on the same host as CasOS. It installs an SSH key into the distro so the machine can be managed exactly like a remote SSH machine, without asking the user for an IP address, port, username or password.

Index

• Constants
• func Available() error
• func EnsureSystemd(ctx context.Context, distro string, log func(string)) (bool, error)
• type Distro
  • func (d Distro) Usable() bool
• type ProvisionResult
  • func Provision(ctx context.Context, distro, publicKey string) (*ProvisionResult, error)
• type Status
  • func Detect(ctx context.Context) (*Status, error)
  • func Install(ctx context.Context, distro string, log func(string)) (*Status, error)
  • func (s *Status) NodeDistro() *Distro

Constants

const DefaultInstallDistro = "Ubuntu"

DefaultInstallDistro is the distribution CasOS installs when the host has no distro it can turn into a worker node. Ubuntu is the WSL default, it ships systemd support and apt, which is what the node deployment expects.

Functions

func Available

func Available() error

Available reports whether the local host can run WSL commands at all.

func EnsureSystemd

func EnsureSystemd(ctx context.Context, distro string, log func(string)) (bool, error)

EnsureSystemd makes distro boot with systemd, which the kubelet and kube-proxy services require. It reports whether the distro had to be restarted, and only restarts one that was not running systemd already.

Types

type Distro

type Distro struct {
	Name    string `json:"name"`
	State   string `json:"state"`
	Version int    `json:"version"`
	Default bool   `json:"default"`
}

Distro is one registered WSL distribution.

func (Distro) Usable

func (d Distro) Usable() bool

Usable reports whether a worker node can be deployed into this distro. WSL 1 has no real kernel and cannot run systemd, which the node services need.

type ProvisionResult

type ProvisionResult struct {
	Distro   string   `json:"distro"`
	Os       string   `json:"os"`
	Username string   `json:"username"`
	Port     int      `json:"port"`
	Hosts    []string `json:"hosts"`
	// Warnings holds non fatal problems, for example sshd that was already
	// running. They are only interesting when the SSH check later fails.
	Warnings []string `json:"warnings,omitempty"`
}

ProvisionResult describes the local WSL distro after sshd has been prepared.

func Provision

func Provision(ctx context.Context, distro, publicKey string) (*ProvisionResult, error)

Provision makes sure sshd runs inside distro and authorizes publicKey for both the distro's login user and root. An empty distro means the default one. It returns the addresses the caller can use to reach the distro over SSH.

type Status

type Status struct {
	CLIAvailable bool     `json:"cliAvailable"`
	Distros      []Distro `json:"distros"`
	// Detail carries what wsl.exe said when no distro could be listed, which is
	// the only useful hint about why WSL is not usable yet.
	Detail string `json:"detail,omitempty"`
}

Status describes the WSL installation of the local Windows host.

func Detect

func Detect(ctx context.Context) (*Status, error)

Detect reports what WSL looks like on this host. A host without WSL is not an error: it is the state Install exists to fix.

func Install

func Install(ctx context.Context, distro string, log func(string)) (*Status, error)

Install registers distro, installing WSL itself first when the host does not have it yet. The distro is not launched, so its interactive first-run setup never asks the user for an account: CasOS only ever runs commands as root.

It returns the detected distros afterwards so the caller can tell an install that finished from one that needs Windows to restart first.

func (*Status) NodeDistro

func (s *Status) NodeDistro() *Distro

NodeDistro returns the distro CasOS should enroll: the default one when it is usable, otherwise the first usable one.