(updated with latest main) Allow setting environment variables using the build image

.gitignore

@@ -5,7 +5,7 @@
 *~
 .tool-versions
 /out
-
+.vscode
 acceptance/testdata/*/**/container/cnb/lifecycle/*
 acceptance/testdata/*/**/container/docker-config/*
 acceptance/testdata/exporter/container/layers/*analyzed.toml

Makefile

@@ -342,4 +342,3 @@ docker-run-windows:
 	docker run -v lifecycle-out:c:/lifecycle/out -e LIFECYCLE_VERSION -e PLATFORM_API -e BUILDPACK_API -v gopathcache:c:/gopath -v '\\.\pipe\docker_engine:\\.\pipe\docker_engine' --isolation=process --interactive --tty --rm $(SOURCE_COMPILATION_IMAGE) $(DOCKER_CMD)
 	docker run -v lifecycle-out:c:/lifecycle/out --rm $(SOURCE_COMPILATION_IMAGE) tar -cf- out | tar -xf-
 	@docker volume rm -f lifecycle-out
-

builder.go

@@ -28,21 +28,22 @@ type Platform interface {
 type BuildEnv interface {
 	AddRootDir(baseDir string) error
 	AddEnvDir(envDir string, defaultAction env.ActionType) error
-	WithPlatform(platformDir string) ([]string, error)
+	WithOverrides(platformDir string, baseConfigDir string) ([]string, error)
 	List() []string
 }
 
 type Builder struct {
-	AppDir        string
-	LayersDir     string
-	PlatformDir   string
-	BuildExecutor buildpack.BuildExecutor
-	DirStore      DirStore
-	Group         buildpack.Group
-	Logger        log.Logger
-	Out, Err      io.Writer
-	Plan          platform.BuildPlan
-	PlatformAPI   *api.Version
+	AppDir         string
+	BuildConfigDir string
+	LayersDir      string
+	PlatformDir    string
+	BuildExecutor  buildpack.BuildExecutor
+	DirStore       DirStore
+	Group          buildpack.Group
+	Logger         log.Logger
+	Out, Err       io.Writer
+	Plan           platform.BuildPlan
+	PlatformAPI    *api.Version
 }
 
 func (b *Builder) Build() (*platform.BuildMetadata, error) {
@@ -61,10 +62,7 @@ func (b *Builder) Build() (*platform.BuildMetadata, error) {
 		slices    []layers.Slice
 	)
 	processMap := newProcessMap()
-	inputs, err := b.getCommonInputs()
-	if err != nil {
-		return nil, err
-	}
+	inputs := b.getBuildInputs()
 	inputs.Env = env.NewBuildEnv(os.Environ())
 	filteredPlan := b.Plan
 
@@ -113,8 +111,7 @@ func (b *Builder) Build() (*platform.BuildMetadata, error) {
 
 	if b.PlatformAPI.AtLeast("0.8") {
 		b.Logger.Debug("Copying SBOM files")
-		err = b.copySBOMFiles(inputs.LayersDir, bomFiles)
-		if err != nil {
+		if err := b.copySBOMFiles(inputs.LayersDir, bomFiles); err != nil {
 			return nil, err
 		}
 	}
@@ -150,27 +147,15 @@ func (b *Builder) Build() (*platform.BuildMetadata, error) {
 	}, nil
 }
 
-func (b *Builder) getCommonInputs() (buildpack.BuildInputs, error) {
-	appDir, err := filepath.Abs(b.AppDir)
-	if err != nil {
-		return buildpack.BuildInputs{}, err
-	}
-	layersDir, err := filepath.Abs(b.LayersDir)
-	if err != nil {
-		return buildpack.BuildInputs{}, err
-	}
-	platformDir, err := filepath.Abs(b.PlatformDir)
-	if err != nil {
-		return buildpack.BuildInputs{}, err
-	}
-
+func (b *Builder) getBuildInputs() buildpack.BuildInputs {
 	return buildpack.BuildInputs{
-		AppDir:      appDir,
-		LayersDir:   layersDir,
-		PlatformDir: platformDir,
-		Out:         b.Out,
-		Err:         b.Err,
-	}, nil
+		AppDir:         b.AppDir,
+		BuildConfigDir: b.BuildConfigDir,
+		LayersDir:      b.LayersDir,
+		PlatformDir:    b.PlatformDir,
+		Out:            b.Out,
+		Err:            b.Err,
+	}
 }
 
 // copySBOMFiles() copies any BOM files written by buildpacks during the Build() process

builder_test.go

@@ -152,6 +152,9 @@ func testBuilder(t *testing.T, when spec.G, it spec.S) {
 			}}
 			executor.EXPECT().Build(*bpA, gomock.Any(), gomock.Any()).DoAndReturn(
 				func(_ buildpack.BpDescriptor, inputs buildpack.BuildInputs, _ llog.Logger) (buildpack.BuildOutputs, error) {
+					h.AssertEq(t, inputs.AppDir, builder.AppDir)
+					h.AssertEq(t, inputs.BuildConfigDir, builder.BuildConfigDir)
+					h.AssertEq(t, inputs.PlatformDir, builder.PlatformDir)
 					h.AssertEq(t, inputs.Plan, expectedPlanA)
 					return buildpack.BuildOutputs{
 						MetRequires: []string{"some-dep"},
@@ -164,6 +167,9 @@ func testBuilder(t *testing.T, when spec.G, it spec.S) {
 			}}
 			executor.EXPECT().Build(*bpB, gomock.Any(), gomock.Any()).Do(
 				func(_ buildpack.BpDescriptor, inputs buildpack.BuildInputs, _ llog.Logger) (buildpack.BuildOutputs, error) {
+					h.AssertEq(t, inputs.AppDir, builder.AppDir)
+					h.AssertEq(t, inputs.BuildConfigDir, builder.BuildConfigDir)
+					h.AssertEq(t, inputs.PlatformDir, builder.PlatformDir)
 					h.AssertEq(t, inputs.Plan, expectedPlanB)
 					return buildpack.BuildOutputs{}, nil
 				})

buildpack/build.go

@@ -30,18 +30,19 @@ const (
 )
 
 type BuildInputs struct {
-	AppDir      string
-	LayersDir   string
-	PlatformDir string
-	Env         BuildEnv
-	Out, Err    io.Writer
-	Plan        Plan
+	AppDir         string
+	BuildConfigDir string
+	LayersDir      string
+	PlatformDir    string
+	Env            BuildEnv
+	Out, Err       io.Writer
+	Plan           Plan
 }
 
 type BuildEnv interface {
 	AddRootDir(baseDir string) error
 	AddEnvDir(envDir string, defaultAction env.ActionType) error
-	WithPlatform(platformDir string) ([]string, error)
+	WithOverrides(platformDir string, buildConfigDir string) ([]string, error)
 	List() []string
 }
 
@@ -138,12 +139,12 @@ func runBuildCmd(d BpDescriptor, bpLayersDir, planPath string, inputs BuildInput
 
 	var err error
 	if d.Buildpack.ClearEnv {
-		cmd.Env = buildEnv.List()
+		cmd.Env, err = buildEnv.WithOverrides("", inputs.BuildConfigDir)
 	} else {
-		cmd.Env, err = buildEnv.WithPlatform(inputs.PlatformDir)
-		if err != nil {
-			return err
-		}
+		cmd.Env, err = buildEnv.WithOverrides(inputs.PlatformDir, inputs.BuildConfigDir)
+	}
+	if err != nil {
+		return err
 	}
 	cmd.Env = append(cmd.Env, EnvBuildpackDir+"="+d.WithRootDir)
 	if api.MustParse(d.WithAPI).AtLeast("0.8") {
@@ -154,7 +155,7 @@ func runBuildCmd(d BpDescriptor, bpLayersDir, planPath string, inputs BuildInput
 		)
 	}
 
-	if err := cmd.Run(); err != nil {
+	if err = cmd.Run(); err != nil {
 		return NewError(err, ErrTypeBuildpack)
 	}
 	return nil

buildpack/build_test.go

@@ -51,6 +51,7 @@ func testBuild(t *testing.T, when spec.G, it spec.S) {
 		inputs         buildpack.BuildInputs
 		tmpDir         string
 		appDir         string
+		buildConfigDir string
 		layersDir      string
 		platformDir    string
 		mockEnv        *testmock.MockBuildEnv
@@ -87,34 +88,35 @@ func testBuild(t *testing.T, when spec.G, it spec.S) {
 		h.AssertNil(t, err)
 		layersDir = filepath.Join(tmpDir, "launch")
 		appDir = filepath.Join(layersDir, "app")
+		buildConfigDir = filepath.Join(tmpDir, "build-config")
 		platformDir = filepath.Join(tmpDir, "platform")
 		h.Mkdir(t, layersDir, appDir, filepath.Join(platformDir, "env"))
 
 		// make inputs
 		mockEnv = testmock.NewMockBuildEnv(mockCtrl)
 		stdout, stderr = &bytes.Buffer{}, &bytes.Buffer{}
 		inputs = buildpack.BuildInputs{
-			AppDir:      appDir,
-			LayersDir:   layersDir,
-			PlatformDir: platformDir,
-			Env:         mockEnv,
-			Out:         stdout,
-			Err:         stderr,
+			AppDir:         appDir,
+			BuildConfigDir: buildConfigDir,
+			LayersDir:      layersDir,
+			PlatformDir:    platformDir,
+			Env:            mockEnv,
+			Out:            stdout,
+			Err:            stderr,
 		}
-
 		logger = &log.Logger{Handler: logHandler}
 	})
 
 	it.After(func() {
-		os.RemoveAll(tmpDir)
+		_ = os.RemoveAll(tmpDir)
 		mockCtrl.Finish()
 	})
 
 	when("#Build", func() {
 		when("env", func() {
 			when("clear", func() {
 				it.Before(func() {
-					mockEnv.EXPECT().List().Return(append(os.Environ(), "TEST_ENV=cleared"))
+					mockEnv.EXPECT().WithOverrides("", buildConfigDir).Return(append(os.Environ(), "TEST_ENV=cleared"), nil)
 
 					descriptor.Buildpack.Version = "v1.clear"
 					descriptor.WithRootDir = filepath.Join(dirStore, "A", "v1.clear")
@@ -163,7 +165,7 @@ func testBuild(t *testing.T, when spec.G, it spec.S) {
 
 			when("full", func() {
 				it.Before(func() {
-					mockEnv.EXPECT().WithPlatform(platformDir).Return(append(os.Environ(), "TEST_ENV=Av1"), nil)
+					mockEnv.EXPECT().WithOverrides(platformDir, buildConfigDir).Return(append(os.Environ(), "TEST_ENV=Av1"), nil)
 				})
 
 				it("provides a full env", func() {
@@ -219,7 +221,7 @@ func testBuild(t *testing.T, when spec.G, it spec.S) {
 			})
 
 			it("errors when <platform>/env cannot be loaded", func() {
-				mockEnv.EXPECT().WithPlatform(platformDir).Return(nil, errors.New("some error"))
+				mockEnv.EXPECT().WithOverrides(platformDir, buildConfigDir).Return(nil, errors.New("some error"))
 				if _, err := executor.Build(descriptor, inputs, logger); err == nil {
 					t.Fatal("Expected error.\n")
 				} else if !strings.Contains(err.Error(), "some error") {
@@ -229,7 +231,7 @@ func testBuild(t *testing.T, when spec.G, it spec.S) {
 
 			when("any", func() {
 				it.Before(func() {
-					mockEnv.EXPECT().WithPlatform(platformDir).Return(append(os.Environ(), "TEST_ENV=Av1"), nil).AnyTimes()
+					mockEnv.EXPECT().WithOverrides(platformDir, buildConfigDir).Return(append(os.Environ(), "TEST_ENV=Av1"), nil).AnyTimes()
 				})
 
 				it("ensures the buildpack's layers dir exists and processes build layers", func() {
@@ -301,6 +303,7 @@ func testBuild(t *testing.T, when spec.G, it spec.S) {
 					var appendErr error
 
 					it.Before(func() {
+						mockEnv.EXPECT().WithOverrides(platformDir, buildConfigDir).Return(append(os.Environ(), "TEST_ENV=Av1"), nil).AnyTimes()
 						appendErr = errors.New("some error")
 					})
 

buildpack/detect.go

@@ -26,9 +26,10 @@ const (
 )
 
 type DetectInputs struct {
-	AppDir      string
-	PlatformDir string
-	Env         BuildEnv
+	AppDir         string
+	BuildConfigDir string
+	PlatformDir    string
+	Env            BuildEnv
 }
 
 type DetectOutputs struct {
@@ -57,18 +58,13 @@ func (e *DefaultDetectExecutor) Detect(d Descriptor, inputs DetectInputs, logger
 }
 
 func detectBp(d BpDescriptor, inputs DetectInputs, logger log.Logger) DetectOutputs {
-	appDir, platformDir, err := processPlatformPaths(inputs)
-	if err != nil {
-		return DetectOutputs{Code: -1, Err: err}
-	}
-
 	planDir, planPath, err := processBuildpackPaths()
 	defer os.RemoveAll(planDir)
 	if err != nil {
 		return DetectOutputs{Code: -1, Err: err}
 	}
 
-	result := runDetect(&d, platformDir, planPath, appDir, inputs.Env, EnvBuildpackDir)
+	result := runDetect(&d, inputs, planPath, EnvBuildpackDir)
 	if result.Code != 0 {
 		return result
 	}
@@ -99,11 +95,6 @@ func detectBp(d BpDescriptor, inputs DetectInputs, logger log.Logger) DetectOutp
 }
 
 func detectExt(d ExtDescriptor, inputs DetectInputs, logger log.Logger) DetectOutputs {
-	appDir, platformDir, err := processPlatformPaths(inputs)
-	if err != nil {
-		return DetectOutputs{Code: -1, Err: err}
-	}
-
 	planDir, planPath, err := processBuildpackPaths()
 	defer os.RemoveAll(planDir)
 	if err != nil {
@@ -119,7 +110,7 @@ func detectExt(d ExtDescriptor, inputs DetectInputs, logger log.Logger) DetectOu
 			return DetectOutputs{Code: -1, Err: err}
 		}
 	} else {
-		result = runDetect(&d, platformDir, planPath, appDir, inputs.Env, EnvExtensionDir)
+		result = runDetect(&d, inputs, planPath, EnvExtensionDir)
 		if result.Code != 0 {
 			return result
 		}
@@ -144,18 +135,6 @@ func detectExt(d ExtDescriptor, inputs DetectInputs, logger log.Logger) DetectOu
 	return result
 }
 
-func processPlatformPaths(inputs DetectInputs) (string, string, error) {
-	appDir, err := filepath.Abs(inputs.AppDir)
-	if err != nil {
-		return "", "", nil
-	}
-	platformDir, err := filepath.Abs(inputs.PlatformDir)
-	if err != nil {
-		return "", "", nil
-	}
-	return appDir, platformDir, nil
-}
-
 func processBuildpackPaths() (string, string, error) {
 	planDir, err := os.MkdirTemp("", "plan.")
 	if err != nil {
@@ -174,31 +153,31 @@ type detectable interface {
 	RootDir() string
 }
 
-func runDetect(d detectable, platformDir, planPath, appDir string, bpEnv BuildEnv, envRootDirKey string) DetectOutputs {
+func runDetect(d detectable, inputs DetectInputs, planPath string, envRootDirKey string) DetectOutputs {
 	out := &bytes.Buffer{}
 	cmd := exec.Command(
 		filepath.Join(d.RootDir(), "bin", "detect"),
-		platformDir,
+		inputs.PlatformDir,
 		planPath,
 	) // #nosec G204
-	cmd.Dir = appDir
+	cmd.Dir = inputs.AppDir
 	cmd.Stdout = out
 	cmd.Stderr = out
 
 	var err error
 	if d.ClearEnv() {
-		cmd.Env = bpEnv.List()
+		cmd.Env, err = inputs.Env.WithOverrides("", inputs.BuildConfigDir)
 	} else {
-		cmd.Env, err = bpEnv.WithPlatform(platformDir)
-		if err != nil {
-			return DetectOutputs{Code: -1, Err: err}
-		}
+		cmd.Env, err = inputs.Env.WithOverrides(inputs.PlatformDir, inputs.BuildConfigDir)
+	}
+	if err != nil {
+		return DetectOutputs{Code: -1, Err: err}
 	}
 	cmd.Env = append(cmd.Env, envRootDirKey+"="+d.RootDir())
 	if api.MustParse(d.API()).AtLeast("0.8") {
 		cmd.Env = append(
 			cmd.Env,
-			EnvPlatformDir+"="+platformDir,
+			EnvPlatformDir+"="+inputs.PlatformDir,
 			EnvBuildPlanPath+"="+planPath,
 		)
 	}