DockerCLI/cmd/docker/docker.go

463 lines
13 KiB
Go

package main
import (
"fmt"
"os"
"os/exec"
"strings"
"syscall"
"github.com/docker/cli/cli"
pluginmanager "github.com/docker/cli/cli-plugins/manager"
"github.com/docker/cli/cli/command"
"github.com/docker/cli/cli/command/commands"
cliflags "github.com/docker/cli/cli/flags"
"github.com/docker/cli/cli/version"
"github.com/docker/docker/api/types/versions"
"github.com/moby/buildkit/util/appcontext"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
"github.com/spf13/cobra"
"github.com/spf13/pflag"
)
func newDockerCommand(dockerCli *command.DockerCli) *cli.TopLevelCommand {
var (
opts *cliflags.ClientOptions
flags *pflag.FlagSet
helpCmd *cobra.Command
)
cmd := &cobra.Command{
Use: "docker [OPTIONS] COMMAND [ARG...]",
Short: "A self-sufficient runtime for containers",
SilenceUsage: true,
SilenceErrors: true,
TraverseChildren: true,
RunE: func(cmd *cobra.Command, args []string) error {
if len(args) == 0 {
return command.ShowHelp(dockerCli.Err())(cmd, args)
}
return fmt.Errorf("docker: '%s' is not a docker command.\nSee 'docker --help'", args[0])
},
PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
return isSupported(cmd, dockerCli)
},
Version: fmt.Sprintf("%s, build %s", version.Version, version.GitCommit),
DisableFlagsInUseLine: true,
CompletionOptions: cobra.CompletionOptions{
DisableDefaultCmd: false,
HiddenDefaultCmd: true,
DisableDescriptions: true,
},
}
opts, flags, helpCmd = cli.SetupRootCommand(cmd)
registerCompletionFuncForGlobalFlags(dockerCli, cmd)
flags.BoolP("version", "v", false, "Print version information and quit")
setFlagErrorFunc(dockerCli, cmd)
setupHelpCommand(dockerCli, cmd, helpCmd)
setHelpFunc(dockerCli, cmd)
cmd.SetOut(dockerCli.Out())
commands.AddCommands(cmd, dockerCli)
cli.DisableFlagsInUseLine(cmd)
setValidateArgs(dockerCli, cmd)
// flags must be the top-level command flags, not cmd.Flags()
return cli.NewTopLevelCommand(cmd, dockerCli, opts, flags)
}
func setFlagErrorFunc(dockerCli command.Cli, cmd *cobra.Command) {
// When invoking `docker stack --nonsense`, we need to make sure FlagErrorFunc return appropriate
// output if the feature is not supported.
// As above cli.SetupRootCommand(cmd) have already setup the FlagErrorFunc, we will add a pre-check before the FlagErrorFunc
// is called.
flagErrorFunc := cmd.FlagErrorFunc()
cmd.SetFlagErrorFunc(func(cmd *cobra.Command, err error) error {
if err := pluginmanager.AddPluginCommandStubs(dockerCli, cmd.Root()); err != nil {
return err
}
if err := isSupported(cmd, dockerCli); err != nil {
return err
}
if err := hideUnsupportedFeatures(cmd, dockerCli); err != nil {
return err
}
return flagErrorFunc(cmd, err)
})
}
func setupHelpCommand(dockerCli command.Cli, rootCmd, helpCmd *cobra.Command) {
origRun := helpCmd.Run
origRunE := helpCmd.RunE
helpCmd.Run = nil
helpCmd.RunE = func(c *cobra.Command, args []string) error {
if len(args) > 0 {
helpcmd, err := pluginmanager.PluginRunCommand(dockerCli, args[0], rootCmd)
if err == nil {
return helpcmd.Run()
}
if !pluginmanager.IsNotFound(err) {
return errors.Errorf("unknown help topic: %v", strings.Join(args, " "))
}
}
if origRunE != nil {
return origRunE(c, args)
}
origRun(c, args)
return nil
}
}
func tryRunPluginHelp(dockerCli command.Cli, ccmd *cobra.Command, cargs []string) error {
root := ccmd.Root()
cmd, _, err := root.Traverse(cargs)
if err != nil {
return err
}
helpcmd, err := pluginmanager.PluginRunCommand(dockerCli, cmd.Name(), root)
if err != nil {
return err
}
return helpcmd.Run()
}
func setHelpFunc(dockerCli command.Cli, cmd *cobra.Command) {
defaultHelpFunc := cmd.HelpFunc()
cmd.SetHelpFunc(func(ccmd *cobra.Command, args []string) {
if pluginmanager.IsPluginCommand(ccmd) {
err := tryRunPluginHelp(dockerCli, ccmd, args)
if !pluginmanager.IsNotFound(err) {
ccmd.Println(err)
}
cmd.PrintErrf("unknown help topic: %v\n", ccmd.Name())
return
}
if err := isSupported(ccmd, dockerCli); err != nil {
ccmd.Println(err)
return
}
if err := hideUnsupportedFeatures(ccmd, dockerCli); err != nil {
ccmd.Println(err)
return
}
defaultHelpFunc(ccmd, args)
})
}
func setValidateArgs(dockerCli command.Cli, cmd *cobra.Command) {
// The Args is handled by ValidateArgs in cobra, which does not allows a pre-hook.
// As a result, here we replace the existing Args validation func to a wrapper,
// where the wrapper will check to see if the feature is supported or not.
// The Args validation error will only be returned if the feature is supported.
cli.VisitAll(cmd, func(ccmd *cobra.Command) {
// if there is no tags for a command or any of its parent,
// there is no need to wrap the Args validation.
if !hasTags(ccmd) {
return
}
if ccmd.Args == nil {
return
}
cmdArgs := ccmd.Args
ccmd.Args = func(cmd *cobra.Command, args []string) error {
if err := isSupported(cmd, dockerCli); err != nil {
return err
}
return cmdArgs(cmd, args)
}
})
}
func tryPluginRun(dockerCli command.Cli, cmd *cobra.Command, subcommand string, envs []string) error {
plugincmd, err := pluginmanager.PluginRunCommand(dockerCli, subcommand, cmd)
if err != nil {
return err
}
plugincmd.Env = append(envs, plugincmd.Env...)
go func() {
// override SIGTERM handler so we let the plugin shut down first
<-appcontext.Context().Done()
}()
if err := plugincmd.Run(); err != nil {
statusCode := 1
exitErr, ok := err.(*exec.ExitError)
if !ok {
return err
}
if ws, ok := exitErr.Sys().(syscall.WaitStatus); ok {
statusCode = ws.ExitStatus()
}
return cli.StatusError{
StatusCode: statusCode,
}
}
return nil
}
func runDocker(dockerCli *command.DockerCli) error {
tcmd := newDockerCommand(dockerCli)
cmd, args, err := tcmd.HandleGlobalFlags()
if err != nil {
return err
}
if err := tcmd.Initialize(); err != nil {
return err
}
var envs []string
args, os.Args, envs, err = processAliases(dockerCli, cmd, args, os.Args)
if err != nil {
return err
}
err = pluginmanager.AddPluginCommandStubs(dockerCli, cmd)
if err != nil {
return err
}
if len(args) > 0 {
ccmd, _, err := cmd.Find(args)
if err != nil || pluginmanager.IsPluginCommand(ccmd) {
err := tryPluginRun(dockerCli, cmd, args[0], envs)
if !pluginmanager.IsNotFound(err) {
return err
}
// For plugin not found we fall through to
// cmd.Execute() which deals with reporting
// "command not found" in a consistent way.
}
}
// We've parsed global args already, so reset args to those
// which remain.
cmd.SetArgs(args)
return cmd.Execute()
}
func main() {
dockerCli, err := command.NewDockerCli()
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
logrus.SetOutput(dockerCli.Err())
if err := runDocker(dockerCli); err != nil {
if sterr, ok := err.(cli.StatusError); ok {
if sterr.Status != "" {
fmt.Fprintln(dockerCli.Err(), sterr.Status)
}
// StatusError should only be used for errors, and all errors should
// have a non-zero exit status, so never exit with 0
if sterr.StatusCode == 0 {
os.Exit(1)
}
os.Exit(sterr.StatusCode)
}
fmt.Fprintln(dockerCli.Err(), err)
os.Exit(1)
}
}
type versionDetails interface {
CurrentVersion() string
ServerInfo() command.ServerInfo
}
func hideFlagIf(f *pflag.Flag, condition func(string) bool, annotation string) {
if f.Hidden {
return
}
var val string
if values, ok := f.Annotations[annotation]; ok {
if len(values) > 0 {
val = values[0]
}
if condition(val) {
f.Hidden = true
}
}
}
func hideSubcommandIf(subcmd *cobra.Command, condition func(string) bool, annotation string) {
if subcmd.Hidden {
return
}
if v, ok := subcmd.Annotations[annotation]; ok {
if condition(v) {
subcmd.Hidden = true
}
}
}
func hideUnsupportedFeatures(cmd *cobra.Command, details versionDetails) error {
var (
notExperimental = func(_ string) bool { return !details.ServerInfo().HasExperimental }
notOSType = func(v string) bool { return v != details.ServerInfo().OSType }
notSwarmStatus = func(v string) bool {
s := details.ServerInfo().SwarmStatus
if s == nil {
// engine did not return swarm status header
return false
}
switch v {
case "manager":
// requires the node to be a manager
return !s.ControlAvailable
case "active":
// requires swarm to be active on the node (e.g. for swarm leave)
// only hide the command if we're sure the node is "inactive"
// for any other status, assume the "leave" command can still
// be used.
return s.NodeState == "inactive"
case "":
// some swarm commands, such as "swarm init" and "swarm join"
// are swarm-related, but do not require swarm to be active
return false
default:
// ignore any other value for the "swarm" annotation
return false
}
}
versionOlderThan = func(v string) bool { return versions.LessThan(details.CurrentVersion(), v) }
)
cmd.Flags().VisitAll(func(f *pflag.Flag) {
// hide flags not supported by the server
// root command shows all top-level flags
if cmd.Parent() != nil {
if cmds, ok := f.Annotations["top-level"]; ok {
f.Hidden = !findCommand(cmd, cmds)
}
if f.Hidden {
return
}
}
hideFlagIf(f, notExperimental, "experimental")
hideFlagIf(f, notOSType, "ostype")
hideFlagIf(f, notSwarmStatus, "swarm")
hideFlagIf(f, versionOlderThan, "version")
})
for _, subcmd := range cmd.Commands() {
hideSubcommandIf(subcmd, notExperimental, "experimental")
hideSubcommandIf(subcmd, notOSType, "ostype")
hideSubcommandIf(subcmd, notSwarmStatus, "swarm")
hideSubcommandIf(subcmd, versionOlderThan, "version")
}
return nil
}
// Checks if a command or one of its ancestors is in the list
func findCommand(cmd *cobra.Command, commands []string) bool {
if cmd == nil {
return false
}
for _, c := range commands {
if c == cmd.Name() {
return true
}
}
return findCommand(cmd.Parent(), commands)
}
func isSupported(cmd *cobra.Command, details versionDetails) error {
if err := areSubcommandsSupported(cmd, details); err != nil {
return err
}
return areFlagsSupported(cmd, details)
}
func areFlagsSupported(cmd *cobra.Command, details versionDetails) error {
errs := []string{}
cmd.Flags().VisitAll(func(f *pflag.Flag) {
if !f.Changed {
return
}
if !isVersionSupported(f, details.CurrentVersion()) {
errs = append(errs, fmt.Sprintf(`"--%s" requires API version %s, but the Docker daemon API version is %s`, f.Name, getFlagAnnotation(f, "version"), details.CurrentVersion()))
return
}
if !isOSTypeSupported(f, details.ServerInfo().OSType) {
errs = append(errs, fmt.Sprintf(
`"--%s" is only supported on a Docker daemon running on %s, but the Docker daemon is running on %s`,
f.Name,
getFlagAnnotation(f, "ostype"), details.ServerInfo().OSType),
)
return
}
if _, ok := f.Annotations["experimental"]; ok && !details.ServerInfo().HasExperimental {
errs = append(errs, fmt.Sprintf(`"--%s" is only supported on a Docker daemon with experimental features enabled`, f.Name))
}
// buildkit-specific flags are noop when buildkit is not enabled, so we do not add an error in that case
})
if len(errs) > 0 {
return errors.New(strings.Join(errs, "\n"))
}
return nil
}
// Check recursively so that, e.g., `docker stack ls` returns the same output as `docker stack`
func areSubcommandsSupported(cmd *cobra.Command, details versionDetails) error {
// Check recursively so that, e.g., `docker stack ls` returns the same output as `docker stack`
for curr := cmd; curr != nil; curr = curr.Parent() {
if cmdVersion, ok := curr.Annotations["version"]; ok && versions.LessThan(details.CurrentVersion(), cmdVersion) {
return fmt.Errorf("%s requires API version %s, but the Docker daemon API version is %s", cmd.CommandPath(), cmdVersion, details.CurrentVersion())
}
if ost, ok := curr.Annotations["ostype"]; ok && ost != details.ServerInfo().OSType {
return fmt.Errorf("%s is only supported on a Docker daemon running on %s, but the Docker daemon is running on %s", cmd.CommandPath(), ost, details.ServerInfo().OSType)
}
if _, ok := curr.Annotations["experimental"]; ok && !details.ServerInfo().HasExperimental {
return fmt.Errorf("%s is only supported on a Docker daemon with experimental features enabled", cmd.CommandPath())
}
}
return nil
}
func getFlagAnnotation(f *pflag.Flag, annotation string) string {
if value, ok := f.Annotations[annotation]; ok && len(value) == 1 {
return value[0]
}
return ""
}
func isVersionSupported(f *pflag.Flag, clientVersion string) bool {
if v := getFlagAnnotation(f, "version"); v != "" {
return versions.GreaterThanOrEqualTo(clientVersion, v)
}
return true
}
func isOSTypeSupported(f *pflag.Flag, osType string) bool {
if v := getFlagAnnotation(f, "ostype"); v != "" && osType != "" {
return osType == v
}
return true
}
// hasTags return true if any of the command's parents has tags
func hasTags(cmd *cobra.Command) bool {
for curr := cmd; curr != nil; curr = curr.Parent() {
if len(curr.Annotations) > 0 {
return true
}
}
return false
}