DockerCLI/cmd/docker/builder.go

118 lines
3.1 KiB
Go

package main
import (
"fmt"
"os"
"strconv"
pluginmanager "github.com/docker/cli/cli-plugins/manager"
"github.com/docker/cli/cli/command"
"github.com/pkg/errors"
"github.com/spf13/cobra"
)
const (
builderDefaultPlugin = "buildx"
buildxMissingWarning = `DEPRECATED: The legacy builder is deprecated and will be removed in a future release.
Install the buildx component to build images with BuildKit:
https://docs.docker.com/go/buildx/
`
buildxMissingError = `ERROR: BuildKit is enabled but the buildx component is missing or broken.
Install the buildx component to build images with BuildKit:
https://docs.docker.com/go/buildx/
`
)
func newBuilderError(warn bool, err error) error {
var errorMsg string
if warn {
errorMsg = buildxMissingWarning
} else {
errorMsg = buildxMissingError
}
if pluginmanager.IsNotFound(err) {
return errors.New(errorMsg)
}
return fmt.Errorf("%w\n\n%s", err, errorMsg)
}
func processBuilder(dockerCli command.Cli, cmd *cobra.Command, args, osargs []string) ([]string, []string, error) {
// check DOCKER_BUILDKIT env var is present and
// if not assume we want to use a builder
var enforcedBuilder bool
if v, ok := os.LookupEnv("DOCKER_BUILDKIT"); ok {
enabled, err := strconv.ParseBool(v)
if err != nil {
return args, osargs, errors.Wrap(err, "DOCKER_BUILDKIT environment variable expects boolean value")
}
if !enabled {
return args, osargs, nil
}
enforcedBuilder = true
}
// if a builder alias is defined, use it instead
// of the default one
isAlias := false
builderAlias := builderDefaultPlugin
aliasMap := dockerCli.ConfigFile().Aliases
if v, ok := aliasMap[keyBuilderAlias]; ok {
isAlias = true
builderAlias = v
}
// wcow build command must use the legacy builder for buildx
// if not opt-in through a builder alias
if !isAlias && dockerCli.ServerInfo().OSType == "windows" {
return args, osargs, nil
}
// are we using a cmd that should be forwarded to the builder?
fwargs, fwosargs, forwarded := forwardBuilder(builderAlias, args, osargs)
if !forwarded {
return args, osargs, nil
}
// check plugin is available if cmd forwarded
plugin, perr := pluginmanager.GetPlugin(builderAlias, dockerCli, cmd.Root())
if perr == nil && plugin != nil {
perr = plugin.Err
}
if perr != nil {
// if builder enforced with DOCKER_BUILDKIT=1, cmd fails if plugin missing or broken
if enforcedBuilder {
return fwargs, fwosargs, newBuilderError(false, perr)
}
// otherwise, display warning and continue
_, _ = fmt.Fprintln(dockerCli.Err(), newBuilderError(true, perr))
return args, osargs, nil
}
return fwargs, fwosargs, nil
}
func forwardBuilder(alias string, args, osargs []string) ([]string, []string, bool) {
aliases := [][2][]string{
{
{"builder"},
{alias},
},
{
{"build"},
{alias, "build"},
},
{
{"image", "build"},
{alias, "build"},
},
}
for _, al := range aliases {
if fwargs, changed := command.StringSliceReplaceAt(args, al[0], al[1], 0); changed {
fwosargs, _ := command.StringSliceReplaceAt(osargs, al[0], al[1], -1)
return fwargs, fwosargs, true
}
}
return args, osargs, false
}