build: handle --network

Signed-off-by: Tibor Vass <tibor@docker.com>

build/build.go

@@ -37,6 +37,7 @@ type Options struct {
 	Pull        bool
 	ImageIDFile string
 	ExtraHosts  []string
+	NetworkMode string
 
 	NoCache   bool
 	Target    string
@@ -228,6 +229,14 @@ func Build(ctx context.Context, drivers []DriverInfo, opt map[string]Options, pw
 			so.FrontendAttrs["platform"] = strings.Join(pp, ",")
 		}
 
+		switch opt.NetworkMode {
+		case "host", "none":
+			so.FrontendAttrs["force-network-mode"] = opt.NetworkMode
+		case "", "default":
+		default:
+			return nil, errors.Errorf("network mode %q not supported by buildkit", opt.NetworkMode)
+		}
+
 		extraHosts, err := toBuildkitExtraHosts(opt.ExtraHosts)
 		if err != nil {
 			return nil, err

commands/build.go

@@ -32,11 +32,11 @@ type buildOptions struct {
 	outputs     []string
 	imageIDFile string
 	extraHosts  []string
+	networkMode string
 
 	// unimplemented
 	squash bool
 	quiet  bool
-	networkMode string
 
 	// hidden
 	// untrusted   bool
@@ -68,9 +68,6 @@ func runBuild(dockerCli command.Cli, in buildOptions) error {
 	if in.quiet {
 		return errors.Errorf("quiet currently not implemented")
 	}
-	if in.networkMode != "default" {
-		return errors.Errorf("network currently not implemented")
-	}
 
 	ctx := appcontext.Context()
 
@@ -88,6 +85,7 @@ func runBuild(dockerCli command.Cli, in buildOptions) error {
 		Target:      in.target,
 		ImageIDFile: in.imageIDFile,
 		ExtraHosts:  in.extraHosts,
+		NetworkMode: in.networkMode,
 	}
 
 	platforms, err := build.ParsePlatformSpecs(in.platforms)
@@ -166,7 +164,6 @@ func buildCmd(dockerCli command.Cli) *cobra.Command {
 	flags.StringVar(&options.imageIDFile, "iidfile", "", "Write the image ID to the file")
 	flags.BoolVar(&options.squash, "squash", false, "Squash newly built layers into a single new layer")
 	flags.MarkHidden("quiet")
-	flags.MarkHidden("network")
 	flags.MarkHidden("squash")
 
 	// hidden flags