builder: remove alias logic

The aliases (configurable through the `~/.docker/config.json`) were a temporary
solution while buildx was not yet the default. They're an internal-use (undocumented)
option, so we don't have to take other uses into account.

This removes some of the logic to read the aliasses-config from the configuration
file, and hard-codes it to assume `buildx`.

Co-authored-by: Sebastiaan van Stijn <github@gone.nl>

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

cmd/docker/builder.go

@@ -59,17 +59,8 @@ func processBuilder(dockerCli command.Cli, cmd *cobra.Command, args, osargs []st
 		}
 	}
 
-	// if a builder alias is defined, use it instead
-	// of the default one
-	builderAlias := builderDefaultPlugin
-	aliasMap := dockerCli.ConfigFile().Aliases
-	if v, ok := aliasMap[keyBuilderAlias]; ok {
-		useBuilder = true
-		builderAlias = v
-	}
-
 	// is this a build that should be forwarded to the builder?
-	fwargs, fwosargs, forwarded := forwardBuilder(builderAlias, args, osargs)
+	fwargs, fwosargs, forwarded := forwardBuilder(args, osargs)
 	if !forwarded {
 		return args, osargs, nil
 	}
@@ -81,7 +72,7 @@ func processBuilder(dockerCli command.Cli, cmd *cobra.Command, args, osargs []st
 	}
 
 	// check plugin is available if cmd forwarded
-	plugin, perr := pluginmanager.GetPlugin(builderAlias, dockerCli, cmd.Root())
+	plugin, perr := pluginmanager.GetPlugin(builderDefaultPlugin, dockerCli, cmd.Root())
 	if perr == nil && plugin != nil {
 		perr = plugin.Err
 	}
@@ -98,19 +89,19 @@ func processBuilder(dockerCli command.Cli, cmd *cobra.Command, args, osargs []st
 	return fwargs, fwosargs, nil
 }
 
-func forwardBuilder(alias string, args, osargs []string) ([]string, []string, bool) {
+func forwardBuilder(args, osargs []string) ([]string, []string, bool) {
 	aliases := [][2][]string{
 		{
 			{"builder"},
-			{alias},
+			{"buildx"},
 		},
 		{
 			{"build"},
-			{alias, "build"},
+			{"buildx", "build"},
 		},
 		{
 			{"image", "build"},
-			{alias, "build"},
+			{"buildx", "build"},
 		},
 	}
 	for _, al := range aliases {

cmd/docker/docker.go

@@ -228,7 +228,7 @@ func runDocker(dockerCli *command.DockerCli) error {
 		return err
 	}
 
-	args, os.Args, err = processAliases(dockerCli, cmd, args, os.Args)
+	args, os.Args, err = processBuilder(dockerCli, cmd, args, os.Args)
 	if err != nil {
 		return err
 	}