Build debuggable containers

integration/testdata/debug/go/Dockerfile

@@ -1,14 +1,15 @@
 FROM golang:1.12 as builder
 
 COPY app.go .
-# Must use eval to handle GOGCFLAGS with spaces like `-gcflags='all=-N -l'`
-ARG GOGCFLAGS
-RUN eval go build "${GOGCFLAGS}" -o /app .
+ARG SKAFFOLD_GO_GCFLAGS
+ARG SKAFFOLD_GO_LDFLAGS
+# Must use eval to handle gcflags with spaces like `all=-N -l`
+RUN eval go build -gcflags="${SKAFFOLD_GO_GCFLAGS}" -ldflags="${SKAFFOLD_GO_LDFLAGS}" -o /app .
 
 FROM gcr.io/distroless/base
 # `skaffold debug` uses GOTRACEBACK as an indicator of the Go runtime
 ENV GOTRACEBACK=all
 WORKDIR /
 EXPOSE 8080
 COPY --from=builder /app .
-CMD ["/app"]
+CMD ["/app"]

integration/testdata/debug/skaffold.yaml

@@ -15,9 +15,6 @@ build:
     context: python3
   - image: skaffold-debug-go
     context: go
-    docker:
-      buildArgs:
-        GOGCFLAGS: "-gcflags='all=-N -l'"
 
 deploy:
   kubectl:
@@ -57,5 +54,3 @@ profiles:
       context: go
       buildpacks:
         builder: "gcr.io/buildpacks/builder:v1"
-        env:
-        - GOOGLE_GCFLAGS="-gcflags='all=-N -l'"

pkg/skaffold/build/buildpacks/build_test.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/buildpacks/pack"
 
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/config"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/docker"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/latest"
 	"github.com/GoogleContainerTools/skaffold/testutil"
@@ -46,35 +47,69 @@ func TestBuild(t *testing.T) {
 		api             *testutil.FakeAPIClient
 		files           map[string]string
 		pushImages      bool
-		devMode         bool
 		shouldErr       bool
+		mode            config.RunMode
 		expectedOptions *pack.BuildOptions
 	}{
 		{
-			description: "success",
+			description: "success for debug",
 			artifact:    buildpacksArtifact("my/builder", "my/run"),
 			tag:         "img:tag",
+			mode:        config.RunModes.Debug,
 			api:         &testutil.FakeAPIClient{},
 			expectedOptions: &pack.BuildOptions{
 				AppPath:  ".",
 				Builder:  "my/builder",
 				RunImage: "my/run",
-				Env:      map[string]string{},
+				Env:      buildArgsForDebug,
 				Image:    "img:latest",
 			},
 		},
 		{
-			description: "success with buildpacks",
+			description: "success for build",
+			artifact:    buildpacksArtifact("my/builder", "my/run"),
+			tag:         "img:tag",
+			mode:        config.RunModes.Build,
+			api:         &testutil.FakeAPIClient{},
+			expectedOptions: &pack.BuildOptions{
+				AppPath:  ".",
+				Builder:  "my/builder",
+				RunImage: "my/run",
+				NoPull:   true,
+				Env:      buildArgsForDev,
+				Image:    "img:latest",
+			},
+		},
+		{
+			description: "success with buildpacks for debug",
 			artifact:    withTrustedBuilder(withBuildpacks([]string{"my/buildpack", "my/otherBuildpack"}, buildpacksArtifact("my/otherBuilder", "my/otherRun"))),
 			tag:         "img:tag",
 			api:         &testutil.FakeAPIClient{},
+			mode:        config.RunModes.Debug,
 			expectedOptions: &pack.BuildOptions{
 				AppPath:      ".",
 				Builder:      "my/otherBuilder",
 				RunImage:     "my/otherRun",
 				Buildpacks:   []string{"my/buildpack", "my/otherBuildpack"},
 				TrustBuilder: true,
-				Env:          map[string]string{},
+				Env:          buildArgsForDebug,
+				Image:        "img:latest",
+			},
+		},
+		{
+			description: "success with buildpacks for build",
+			artifact:    withTrustedBuilder(withBuildpacks([]string{"my/buildpack", "my/otherBuildpack"}, buildpacksArtifact("my/otherBuilder", "my/otherRun"))),
+			tag:         "img:tag",
+			api:         &testutil.FakeAPIClient{},
+			mode:        config.RunModes.Build,
+			expectedOptions: &pack.BuildOptions{
+				AppPath:      ".",
+				Builder:      "my/otherBuilder",
+				RunImage:     "my/otherRun",
+				Buildpacks:   []string{"my/buildpack", "my/otherBuildpack"},
+				TrustBuilder: true,
+				NoPull:       true,
+				Env:          buildArgsForDev,
 				Image:        "img:latest",
 			},
 		},
@@ -83,6 +118,7 @@ func TestBuild(t *testing.T) {
 			artifact:    buildpacksArtifact("my/builder2", "my/run2"),
 			tag:         "img:tag",
 			api:         &testutil.FakeAPIClient{},
+			mode:        config.RunModes.Build,
 			files: map[string]string{
 				"project.toml": `[[build.env]]
 name = "GOOGLE_RUNTIME_VERSION"
@@ -99,9 +135,9 @@ version = "1.0"
 				Builder:    "my/builder2",
 				RunImage:   "my/run2",
 				Buildpacks: []string{"my/buildpack", "my/[email protected]"},
-				Env: map[string]string{
+				Env: AppendDefaultArgs(config.RunModes.Build, map[string]string{
 					"GOOGLE_RUNTIME_VERSION": "14.3.0",
-				},
+				}),
 				Image: "img:latest",
 			},
 		},
@@ -120,14 +156,15 @@ id = "my/ignored"
 				Builder:    "my/builder3",
 				RunImage:   "my/run3",
 				Buildpacks: []string{"my/buildpack", "my/otherBuildpack"},
-				Env:        map[string]string{},
+				Env:        buildArgsForDev,
 				Image:      "img:latest",
 			},
 		},
 		{
 			description: "Combine env from skaffold.yaml and project.toml",
 			artifact:    withEnv([]string{"KEY1=VALUE1"}, buildpacksArtifact("my/builder4", "my/run4")),
 			tag:         "img:tag",
+			mode:        config.RunModes.Build,
 			api:         &testutil.FakeAPIClient{},
 			files: map[string]string{
 				"project.toml": `[[build.env]]
@@ -139,10 +176,10 @@ value = "VALUE2"
 				AppPath:  ".",
 				Builder:  "my/builder4",
 				RunImage: "my/run4",
-				Env: map[string]string{
+				Env: AppendDefaultArgs(config.RunModes.Build, map[string]string{
 					"KEY1": "VALUE1",
 					"KEY2": "VALUE2",
-				},
+				}),
 				Image: "img:latest",
 			},
 		},
@@ -151,14 +188,14 @@ value = "VALUE2"
 			artifact:    withSync(&latest.Sync{Auto: &latest.Auto{}}, buildpacksArtifact("another/builder", "another/run")),
 			tag:         "img:tag",
 			api:         &testutil.FakeAPIClient{},
-			devMode:     true,
+			mode:        config.RunModes.Dev,
 			expectedOptions: &pack.BuildOptions{
 				AppPath:  ".",
 				Builder:  "another/builder",
 				RunImage: "another/run",
-				Env: map[string]string{
+				Env: AppendDefaultArgs(config.RunModes.Build, map[string]string{
 					"GOOGLE_DEVMODE": "1",
-				},
+				}),
 				Image: "img:latest",
 			},
 		},
@@ -167,12 +204,12 @@ value = "VALUE2"
 			artifact:    buildpacksArtifact("my/other-builder", "my/run"),
 			tag:         "img:tag",
 			api:         &testutil.FakeAPIClient{},
-			devMode:     true,
+			mode:        config.RunModes.Dev,
 			expectedOptions: &pack.BuildOptions{
 				AppPath:  ".",
 				Builder:  "my/other-builder",
 				RunImage: "my/run",
-				Env:      map[string]string{},
+				Env:      buildArgsForDev,
 				Image:    "img:latest",
 			},
 		},
@@ -223,7 +260,7 @@ value = "VALUE2"
 				Add("img:latest", "builtImageID")
 			localDocker := docker.NewLocalDaemon(test.api, nil, false, nil)
 
-			builder := NewArtifactBuilder(localDocker, test.pushImages, test.devMode)
+			builder := NewArtifactBuilder(localDocker, test.pushImages, test.mode)
 			_, err := builder.Build(context.Background(), ioutil.Discard, test.artifact, test.tag)
 
 			t.CheckError(test.shouldErr, err)

pkg/skaffold/build/buildpacks/default_args.go

@@ -0,0 +1,46 @@
+/*
+Copyright 2020 The Skaffold Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package buildpacks
+
+import "github.com/GoogleContainerTools/skaffold/pkg/skaffold/config"
+
+var buildArgsForDebug = map[string]string{
+	"GOOGLE_GOGCFLAGS": "'all=-N -l'", // disable build optimization for Golang
+	// TODO: Add for other languages
+}
+
+var buildArgsForDev = map[string]string{
+	"GOOGLE_GOLDFLAGS": "-w", // omit debug information in build output for Golang
+	// TODO: Add for other languages
+}
+
+func AppendDefaultArgs(mode config.RunMode, existing map[string]string) map[string]string {
+	var args map[string]string
+	switch mode {
+	case config.RunModes.Debug:
+		args = buildArgsForDebug
+	default:
+		args = buildArgsForDev
+	}
+
+	for k, v := range args {
+		if _, found := existing[k]; !found {
+			existing[k] = v
+		}
+	}
+	return existing
+}

pkg/skaffold/build/buildpacks/lifecycle.go

@@ -31,6 +31,7 @@ import (
 	"github.com/buildpacks/pack/project"
 
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/build/misc"
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/config"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/docker"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/latest"
 )
@@ -65,20 +66,21 @@ func (b *Builder) build(ctx context.Context, out io.Writer, a *latest.Artifact,
 	}
 	latest := parsed.BaseName + ":latest"
 
-	// Eveluate Env Vars.
+	// Evaluate Env Vars.
 	envVars, err := misc.EvaluateEnv(artifact.Env)
 	if err != nil {
 		return "", fmt.Errorf("unable to evaluate env variables: %w", err)
 	}
 
-	if b.devMode && a.Sync != nil && a.Sync.Auto != nil {
+	if b.mode == config.RunModes.Dev && a.Sync != nil && a.Sync.Auto != nil {
 		envVars = append(envVars, "GOOGLE_DEVMODE=1")
 	}
 
 	env := envMap(envVars)
 	for _, kv := range projectDescriptor.Build.Env {
 		env[kv.Name] = kv.Value
 	}
+	env = AppendDefaultArgs(b.mode, env)
 
 	// List buildpacks to be used for the build.
 	// Those specified in the skaffold.yaml replace those in the project.toml.

pkg/skaffold/build/buildpacks/types.go

@@ -16,20 +16,23 @@ limitations under the License.
 
 package buildpacks
 
-import "github.com/GoogleContainerTools/skaffold/pkg/skaffold/docker"
+import (
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/config"
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/docker"
+)
 
 // Builder is an artifact builder that uses buildpacks
 type Builder struct {
 	localDocker docker.LocalDaemon
 	pushImages  bool
-	devMode     bool
+	mode        config.RunMode
 }
 
 // NewArtifactBuilder returns a new buildpack artifact builder
-func NewArtifactBuilder(localDocker docker.LocalDaemon, pushImages, devMode bool) *Builder {
+func NewArtifactBuilder(localDocker docker.LocalDaemon, pushImages bool, mode config.RunMode) *Builder {
 	return &Builder{
 		localDocker: localDocker,
 		pushImages:  pushImages,
-		devMode:     devMode,
+		mode:        mode,
 	}
 }

pkg/skaffold/build/cache/cache.go

@@ -85,7 +85,7 @@ func NewCache(runCtx *runcontext.RunContext, imagesAreLocal bool, dependencies D
 		cacheFile:          cacheFile,
 		imagesAreLocal:     imagesAreLocal,
 		hashForArtifact: func(ctx context.Context, a *latest.Artifact) (string, error) {
-			return getHashForArtifact(ctx, dependencies, a, runCtx.DevMode())
+			return getHashForArtifact(ctx, dependencies, a, runCtx.Mode())
 		},
 	}, nil
 }

pkg/skaffold/build/cache/hash.go

@@ -30,6 +30,7 @@ import (
 	"github.com/sirupsen/logrus"
 
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/build/misc"
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/config"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/docker"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/latest"
 )
@@ -40,11 +41,11 @@ var (
 	artifactConfigFunction = artifactConfig
 )
 
-func getHashForArtifact(ctx context.Context, depLister DependencyLister, a *latest.Artifact, devMode bool) (string, error) {
+func getHashForArtifact(ctx context.Context, depLister DependencyLister, a *latest.Artifact, mode config.RunMode) (string, error) {
 	var inputs []string
 
 	// Append the artifact's configuration
-	config, err := artifactConfigFunction(a, devMode)
+	config, err := artifactConfigFunction(a, mode)
 	if err != nil {
 		return "", fmt.Errorf("getting artifact's configuration for %q: %w", a.ImageName, err)
 	}
@@ -72,7 +73,9 @@ func getHashForArtifact(ctx context.Context, depLister DependencyLister, a *late
 
 	// add build args for the artifact if specified
 	if buildArgs := retrieveBuildArgs(a); buildArgs != nil {
-		buildArgs, err := docker.EvaluateBuildArgs(buildArgs)
+		buildArgs, err := docker.EvaluateBuildArgs(buildArgs, func(m map[string]*string) map[string]*string {
+			return docker.AppendDefaultArgs(mode, buildArgs)
+		})
 		if err != nil {
 			return "", fmt.Errorf("evaluating build args: %w", err)
 		}
@@ -100,16 +103,20 @@ func getHashForArtifact(ctx context.Context, depLister DependencyLister, a *late
 }
 
 // TODO(dgageot): when the buildpacks builder image digest changes, we need to change the hash
-func artifactConfig(a *latest.Artifact, devMode bool) (string, error) {
+func artifactConfig(a *latest.Artifact, mode config.RunMode) (string, error) {
 	buf, err := json.Marshal(a.ArtifactType)
 	if err != nil {
 		return "", fmt.Errorf("marshalling the artifact's configuration for %q: %w", a.ImageName, err)
 	}
 
-	if devMode && a.BuildpackArtifact != nil && a.Sync != nil && a.Sync.Auto != nil {
+	if mode == config.RunModes.Dev && a.BuildpackArtifact != nil && a.Sync != nil && a.Sync.Auto != nil {
 		return string(buf) + ".DEV", nil
 	}
 
+	if mode == config.RunModes.Debug {
+		return string(buf) + ".DEBUG", nil
+	}
+
 	return string(buf), nil
 }