Add --build-arg build parameters to docker app build command

Signed-off-by: Guillaume Lours <guillaume.lours@docker.com>

Author: glours

e2e/build_test.go

@@ -68,6 +68,51 @@ func TestBuildWithoutTag(t *testing.T) {
 	})
 }
 
+func TestBuildWithArgs(t *testing.T) {
+	runWithDindSwarmAndRegistry(t, func(info dindSwarmAndRegistryInfo) {
+		cmd := info.configuredCmd
+
+		testDir := path.Join("testdata", "build")
+		cmd.Command = dockerCli.Command("app", "build", "-f", path.Join(testDir, "single.dockerapp"), testDir, "--build-arg", "REPLACE_BY_BUILD_ARG=replaced")
+		icmd.RunCmd(cmd).Assert(t, icmd.Success)
+
+		cfg := getDockerConfigDir(t, cmd)
+
+		f := path.Join(cfg, "app", "bundles", "_ids")
+		infos, err := ioutil.ReadDir(f)
+		assert.NilError(t, err)
+		assert.Equal(t, len(infos), 1)
+		id := infos[0].Name()
+
+		f = path.Join(cfg, "app", "bundles", "_ids", id, "bundle.json")
+		data, err := ioutil.ReadFile(f)
+		assert.NilError(t, err)
+		var bndl bundle.Bundle
+		err = json.Unmarshal(data, &bndl)
+		assert.NilError(t, err)
+
+		cmd.Command = dockerCli.Command("inspect", bndl.Images["worker"].Digest)
+		icmd.RunCmd(cmd).Assert(t, icmd.Expected{
+			ExitCode: 0,
+			Out:      `"com.docker.labelled.arg": "replaced"`,
+		})
+	})
+}
+
+func TestBuildWithArgsDefinedTwice(t *testing.T) {
+	runWithDindSwarmAndRegistry(t, func(info dindSwarmAndRegistryInfo) {
+		cmd := info.configuredCmd
+
+		testDir := path.Join("testdata", "build")
+		cmd.Command = dockerCli.Command("app", "build", "-f", path.Join(testDir, "single.dockerapp"), testDir,
+			"--build-arg", "REPLACE_BY_BUILD_ARG=replaced", "--build-arg", "REPLACE_BY_BUILD_ARG=replaced_twice")
+		icmd.RunCmd(cmd).Assert(t, icmd.Expected{
+			ExitCode: 1,
+			Err:      `'--build-arg REPLACE_BY_BUILD_ARG' is defined twice`,
+		})
+	})
+}
+
 func getDockerConfigDir(t *testing.T, cmd icmd.Cmd) string {
 	var cfg string
 	for _, s := range cmd.Env {

e2e/testdata/build/single.dockerapp/docker-compose.yml

@@ -7,6 +7,9 @@ services:
   worker:
     build:
       context: ./worker
+      args:
+        - REPLACE_BY_BUILD_ARG=original
+        - STATIC_ARG=static
       dockerfile: Dockerfile.worker
   db:
     image: postgres:9.3

e2e/testdata/build/worker/Dockerfile.worker

@@ -1 +1,6 @@
-FROM scratch
+FROM scratch
+ARG REPLACE_BY_BUILD_ARG
+ARG STATIC_ARG
+LABEL com.docker.labelled.arg=$REPLACE_BY_BUILD_ARG
+LABEL com.docker.labelled.optional=$STATIC_ARG
+

internal/commands/build/build.go

@@ -37,6 +37,7 @@ type buildOptions struct {
 	pull     bool
 	tag      string
 	folder   string
+	args     []string
 }
 
 func Cmd(dockerCli command.Cli) *cobra.Command {
@@ -61,6 +62,7 @@ func Cmd(dockerCli command.Cli) *cobra.Command {
 	flags.StringVarP(&opts.tag, "tag", "t", "", "Application image and optionally a tag in the 'image:tag' format")
 	flags.StringVarP(&opts.folder, "folder", "f", "", "Docker app folder containing application definition")
 	flags.BoolVar(&opts.pull, "pull", false, "Always attempt to pull a newer version of the image")
+	flags.StringArrayVar(&opts.args, "build-arg", []string{}, "Set build-time variables")
 
 	return cmd
 }
@@ -71,6 +73,10 @@ func runBuild(dockerCli command.Cli, contextPath string, opt buildOptions) (refe
 		return nil, err
 	}
 
+	if err = checkBuildArgsUniqueness(opt.args); err != nil {
+		return nil, err
+	}
+
 	var ref reference.Reference
 	ref, err = packager.GetNamedTagged(opt.tag)
 	if err != nil {
@@ -242,3 +248,15 @@ func debugSolveResponses(resp map[string]*client.SolveResponse) {
 		}
 	}
 }
+
+func checkBuildArgsUniqueness(args []string) error {
+	set := make(map[string]bool)
+	for _, value := range args {
+		key := strings.Split(value, "=")[0]
+		if _, ok := set[key]; ok {
+			return fmt.Errorf("'--build-arg %s' is defined twice", key)
+		}
+		set[key] = true
+	}
+	return nil
+}

internal/commands/build/compose.go

@@ -18,7 +18,7 @@ func parseCompose(app *types.App, contextPath string, options buildOptions) (map
 		return nil, err
 	}
 
-	services, err := load(parsed)
+	services, err := load(parsed, options.args)
 	if err != nil {
 		return nil, fmt.Errorf("Failed to parse compose file: %s", err)
 	}

internal/commands/build/types.go

@@ -3,6 +3,7 @@ package build
 import (
 	"fmt"
 	"reflect"
+	"strings"
 
 	"github.com/docker/cli/cli/compose/loader"
 	compose "github.com/docker/cli/cli/compose/types"
@@ -24,7 +25,7 @@ type ImageBuildConfig struct {
 	Args       compose.MappingWithEquals `yaml:",omitempty" json:"args,omitempty"`
 }
 
-func load(dict map[string]interface{}) ([]ServiceConfig, error) {
+func load(dict map[string]interface{}, buildArgs []string) ([]ServiceConfig, error) {
 	section, ok := dict["services"]
 	if !ok {
 		return nil, fmt.Errorf("compose file doesn't declare any service")
@@ -33,14 +34,14 @@ func load(dict map[string]interface{}) ([]ServiceConfig, error) {
 	if !ok {
 		return nil, fmt.Errorf("Invalid compose file: 'services' should be a map")
 	}
-	return loadServices(services)
+	return loadServices(services, buildArgs)
 }
 
-func loadServices(servicesDict map[string]interface{}) ([]ServiceConfig, error) {
+func loadServices(servicesDict map[string]interface{}, buildArgs []string) ([]ServiceConfig, error) {
 	var services []ServiceConfig
 
 	for name, serviceDef := range servicesDict {
-		serviceConfig, err := loadService(name, serviceDef.(map[string]interface{}))
+		serviceConfig, err := loadService(name, serviceDef.(map[string]interface{}), buildArgs)
 		if err != nil {
 			return nil, err
 		}
@@ -49,14 +50,19 @@ func loadServices(servicesDict map[string]interface{}) ([]ServiceConfig, error)
 	return services, nil
 }
 
-func loadService(name string, serviceDict map[string]interface{}) (*ServiceConfig, error) {
+func loadService(name string, serviceDict map[string]interface{}, buildArgs []string) (*ServiceConfig, error) {
 	serviceConfig := &ServiceConfig{Name: name}
+	args := buildArgsToMap(buildArgs)
+
 	if err := loader.Transform(serviceDict, serviceConfig, loader.Transformer{
 		TypeOf: reflect.TypeOf(ImageBuildConfig{}),
 		Func:   transformBuildConfig,
 	}); err != nil {
 		return nil, err
 	}
+	if serviceConfig.Build != nil {
+		serviceConfig.Build.mergeArgs(args)
+	}
 	return serviceConfig, nil
 }
 
@@ -70,3 +76,29 @@ func transformBuildConfig(data interface{}) (interface{}, error) {
 		return data, errors.Errorf("invalid type %T for service build", value)
 	}
 }
+
+func buildArgsToMap(array []string) map[string]string {
+	result := make(map[string]string)
+	for _, value := range array {
+		parts := strings.SplitN(value, "=", 2)
+		key := parts[0]
+		if len(parts) == 1 {
+			result[key] = ""
+		} else {
+			result[key] = parts[1]
+		}
+	}
+	return result
+}
+
+func (m ImageBuildConfig) mergeArgs(mapToMerge map[string]string) {
+	for key := range m.Args {
+		if val, ok := mapToMerge[key]; ok {
+			if val == "" {
+				m.Args[key] = nil
+			} else {
+				m.Args[key] = &val
+			}
+		}
+	}
+}