DockerCLI/cmd/docker/docker.go

384 lines
12 KiB
Go

package main
import (
"errors"
"fmt"
"os"
"strings"
"github.com/docker/cli/cli"
"github.com/docker/cli/cli/command"
"github.com/docker/cli/cli/command/commands"
cliconfig "github.com/docker/cli/cli/config"
"github.com/docker/cli/cli/debug"
cliflags "github.com/docker/cli/cli/flags"
"github.com/docker/docker/api/types/versions"
"github.com/docker/docker/client"
"github.com/sirupsen/logrus"
"github.com/spf13/cobra"
"github.com/spf13/pflag"
)
func newDockerCommand(dockerCli *command.DockerCli) *cobra.Command {
opts := cliflags.NewClientOptions()
var flags *pflag.FlagSet
cmd := &cobra.Command{
Use: "docker [OPTIONS] COMMAND [ARG...]",
Short: "A self-sufficient runtime for containers",
SilenceUsage: true,
SilenceErrors: true,
TraverseChildren: true,
Args: noArgs,
RunE: func(cmd *cobra.Command, args []string) error {
return command.ShowHelp(dockerCli.Err())(cmd, args)
},
PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
// flags must be the top-level command flags, not cmd.Flags()
opts.Common.SetDefaultOptions(flags)
dockerPreRun(opts)
if err := dockerCli.Initialize(opts); err != nil {
return err
}
return isSupported(cmd, dockerCli)
},
Version: fmt.Sprintf("%s, build %s", cli.Version, cli.GitCommit),
DisableFlagsInUseLine: true,
}
cli.SetupRootCommand(cmd)
flags = cmd.Flags()
flags.BoolP("version", "v", false, "Print version information and quit")
flags.StringVar(&opts.ConfigDir, "config", cliconfig.Dir(), "Location of client config files")
opts.Common.InstallFlags(flags)
setFlagErrorFunc(dockerCli, cmd, flags, opts)
setHelpFunc(dockerCli, cmd, flags, opts)
cmd.SetOutput(dockerCli.Out())
commands.AddCommands(cmd, dockerCli)
disableFlagsInUseLine(cmd)
setValidateArgs(dockerCli, cmd, flags, opts)
return cmd
}
func disableFlagsInUseLine(cmd *cobra.Command) {
visitAll(cmd, func(ccmd *cobra.Command) {
// do not add a `[flags]` to the end of the usage line.
ccmd.DisableFlagsInUseLine = true
})
}
func setFlagErrorFunc(dockerCli *command.DockerCli, cmd *cobra.Command, flags *pflag.FlagSet, opts *cliflags.ClientOptions) {
// 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 := initializeDockerCli(dockerCli, flags, opts); err != nil {
return err
}
if err := isSupported(cmd, dockerCli); err != nil {
return err
}
return flagErrorFunc(cmd, err)
})
}
func setHelpFunc(dockerCli *command.DockerCli, cmd *cobra.Command, flags *pflag.FlagSet, opts *cliflags.ClientOptions) {
defaultHelpFunc := cmd.HelpFunc()
cmd.SetHelpFunc(func(ccmd *cobra.Command, args []string) {
if err := initializeDockerCli(dockerCli, flags, opts); err != nil {
ccmd.Println(err)
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.DockerCli, cmd *cobra.Command, flags *pflag.FlagSet, opts *cliflags.ClientOptions) {
// 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.
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 := initializeDockerCli(dockerCli, flags, opts); err != nil {
return err
}
if err := isSupported(cmd, dockerCli); err != nil {
return err
}
return cmdArgs(cmd, args)
}
})
}
func initializeDockerCli(dockerCli *command.DockerCli, flags *pflag.FlagSet, opts *cliflags.ClientOptions) error {
if dockerCli.Client() != nil {
return nil
}
// when using --help, PersistentPreRun is not called, so initialization is needed.
// flags must be the top-level command flags, not cmd.Flags()
opts.Common.SetDefaultOptions(flags)
dockerPreRun(opts)
return dockerCli.Initialize(opts)
}
// visitAll will traverse all commands from the root.
// This is different from the VisitAll of cobra.Command where only parents
// are checked.
func visitAll(root *cobra.Command, fn func(*cobra.Command)) {
for _, cmd := range root.Commands() {
visitAll(cmd, fn)
}
fn(root)
}
func noArgs(cmd *cobra.Command, args []string) error {
if len(args) == 0 {
return nil
}
return fmt.Errorf(
"docker: '%s' is not a docker command.\nSee 'docker --help'", args[0])
}
func main() {
dockerCli, err := command.NewDockerCli()
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
logrus.SetOutput(dockerCli.Err())
cmd := newDockerCommand(dockerCli)
if err := cmd.Execute(); 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)
}
}
func dockerPreRun(opts *cliflags.ClientOptions) {
cliflags.SetLogLevel(opts.Common.LogLevel)
if opts.ConfigDir != "" {
cliconfig.SetDir(opts.ConfigDir)
}
if opts.Common.Debug {
debug.Enable()
}
}
type versionDetails interface {
Client() client.APIClient
ClientInfo() command.ClientInfo
ServerInfo() command.ServerInfo
}
func hideFeatureFlag(f *pflag.Flag, hasFeature bool, annotation string) {
if hasFeature {
return
}
if _, ok := f.Annotations[annotation]; ok {
f.Hidden = true
}
}
func hideFeatureSubCommand(subcmd *cobra.Command, hasFeature bool, annotation string) {
if hasFeature {
return
}
if _, ok := subcmd.Annotations[annotation]; ok {
subcmd.Hidden = true
}
}
func hideUnsupportedFeatures(cmd *cobra.Command, details versionDetails) error {
clientVersion := details.Client().ClientVersion()
osType := details.ServerInfo().OSType
hasExperimental := details.ServerInfo().HasExperimental
hasExperimentalCLI := details.ClientInfo().HasExperimental
hasBuildKit, err := command.BuildKitEnabled(details.ServerInfo())
if err != nil {
return err
}
cmd.Flags().VisitAll(func(f *pflag.Flag) {
hideFeatureFlag(f, hasExperimental, "experimental")
hideFeatureFlag(f, hasExperimentalCLI, "experimentalCLI")
hideFeatureFlag(f, hasBuildKit, "buildkit")
hideFeatureFlag(f, !hasBuildKit, "no-buildkit")
// hide flags not supported by the server
if !isOSTypeSupported(f, osType) || !isVersionSupported(f, clientVersion) {
f.Hidden = true
}
// root command shows all top-level flags
if cmd.Parent() != nil {
if commands, ok := f.Annotations["top-level"]; ok {
f.Hidden = !findCommand(cmd, commands)
}
}
})
for _, subcmd := range cmd.Commands() {
hideFeatureSubCommand(subcmd, hasExperimental, "experimental")
hideFeatureSubCommand(subcmd, hasExperimentalCLI, "experimentalCLI")
hideFeatureSubCommand(subcmd, hasBuildKit, "buildkit")
hideFeatureSubCommand(subcmd, !hasBuildKit, "no-buildkit")
// hide subcommands not supported by the server
if subcmdVersion, ok := subcmd.Annotations["version"]; ok && versions.LessThan(clientVersion, subcmdVersion) {
subcmd.Hidden = true
}
if v, ok := subcmd.Annotations["ostype"]; ok && v != osType {
subcmd.Hidden = true
}
}
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 {
clientVersion := details.Client().ClientVersion()
osType := details.ServerInfo().OSType
hasExperimental := details.ServerInfo().HasExperimental
hasExperimentalCLI := details.ClientInfo().HasExperimental
errs := []string{}
cmd.Flags().VisitAll(func(f *pflag.Flag) {
if f.Changed {
if !isVersionSupported(f, clientVersion) {
errs = append(errs, fmt.Sprintf("\"--%s\" requires API version %s, but the Docker daemon API version is %s", f.Name, getFlagAnnotation(f, "version"), clientVersion))
return
}
if !isOSTypeSupported(f, 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"), osType))
return
}
if _, ok := f.Annotations["experimental"]; ok && !hasExperimental {
errs = append(errs, fmt.Sprintf("\"--%s\" is only supported on a Docker daemon with experimental features enabled", f.Name))
}
if _, ok := f.Annotations["experimentalCLI"]; ok && !hasExperimentalCLI {
errs = append(errs, fmt.Sprintf("\"--%s\" is on a Docker cli with experimental cli 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 {
clientVersion := details.Client().ClientVersion()
osType := details.ServerInfo().OSType
hasExperimental := details.ServerInfo().HasExperimental
hasExperimentalCLI := details.ClientInfo().HasExperimental
// 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(clientVersion, cmdVersion) {
return fmt.Errorf("%s requires API version %s, but the Docker daemon API version is %s", cmd.CommandPath(), cmdVersion, clientVersion)
}
if os, ok := curr.Annotations["ostype"]; ok && os != 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(), os, osType)
}
if _, ok := curr.Annotations["experimental"]; ok && !hasExperimental {
return fmt.Errorf("%s is only supported on a Docker daemon with experimental features enabled", cmd.CommandPath())
}
if _, ok := curr.Annotations["experimentalCLI"]; ok && !hasExperimentalCLI {
return fmt.Errorf("%s is only supported on a Docker cli with experimental cli 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
}