Refactors Windows package-buildpack to use baselayer shim

Signed-off-by: Micah Young <[email protected]>

acceptance/acceptance_test.go

@@ -240,8 +240,6 @@ func testWithoutSpecificBuilderRequirement(
 				"pack does not support 'package-buildpack'",
 			)
 
-			h.SkipIf(t, dockerHostOS() == "windows", "These tests are not yet compatible with Windows-based containers")
-
 			var err error
 			tmpDir, err = ioutil.TempDir("", "package-buildpack-tests")
 			assert.Nil(err)

build_test.go

@@ -2253,7 +2253,9 @@ func newWindowsImage(name, topLayerSha string, identifier imgutil.Identifier) *f
 	result := fakes.NewImage(name, topLayerSha, identifier)
 	arch, _ := result.Architecture()
 	osVersion, _ := result.OSVersion()
-	result.SetPlatform("windows", osVersion, arch)
+	result.SetOS("windows")
+	result.SetOSVersion(osVersion)
+	result.SetArchitecture(arch)
 	return result
 }
 

create_builder_test.go

@@ -350,7 +350,7 @@ func testCreateBuilder(t *testing.T, when spec.G, it spec.S) {
 
 						prepareFetcherWithRunImages()
 
-						fakeBuildImage.SetPlatform("windows", "0123", "amd64")
+						h.AssertNil(t, fakeBuildImage.SetOS("windows"))
 						mockImageFetcher.EXPECT().Fetch(gomock.Any(), "some/build-image", true, config.PullAlways).Return(fakeBuildImage, nil)
 
 						err = packClientWithExperimental.CreateBuilder(context.TODO(), opts)
@@ -362,7 +362,7 @@ func testCreateBuilder(t *testing.T, when spec.G, it spec.S) {
 					it("fails", func() {
 						prepareFetcherWithRunImages()
 
-						fakeBuildImage.SetPlatform("windows", "0123", "amd64")
+						h.AssertNil(t, fakeBuildImage.SetOS("windows"))
 						mockImageFetcher.EXPECT().Fetch(gomock.Any(), "some/build-image", true, config.PullAlways).Return(fakeBuildImage, nil)
 
 						err := subject.CreateBuilder(context.TODO(), opts)
@@ -429,7 +429,7 @@ func testCreateBuilder(t *testing.T, when spec.G, it spec.S) {
 					prepareFetcherWithRunImages()
 					opts.Config.Lifecycle.URI = ""
 					opts.Config.Lifecycle.Version = "3.4.5"
-					fakeBuildImage.SetPlatform("windows", "0123", "amd64")
+					h.AssertNil(t, fakeBuildImage.SetOS("windows"))
 
 					mockDownloader.EXPECT().Download(
 						gomock.Any(),
@@ -481,7 +481,7 @@ func testCreateBuilder(t *testing.T, when spec.G, it spec.S) {
 					prepareFetcherWithRunImages()
 					opts.Config.Lifecycle.URI = ""
 					opts.Config.Lifecycle.Version = ""
-					fakeBuildImage.SetPlatform("windows", "0123", "amd64")
+					h.AssertNil(t, fakeBuildImage.SetOS("windows"))
 
 					mockDownloader.EXPECT().Download(
 						gomock.Any(),

go.sum

@@ -45,11 +45,8 @@ github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRF
 github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239 h1:kFOfPq6dUM1hTo4JG6LR5AXSUEsOjtdm0kw0FtQtMJA=
 github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239/go.mod h1:2FmKhYUyUczH0OGQWaF5ceTx0UBShxjsH6f8oGKYe2c=
 github.com/apex/log v1.1.2-0.20190827100214-baa5455d1012/go.mod h1:Ls949n1HFtXfbDcjiTTFQqkVUrte0puoIBfO3SVgwOA=
-github.com/apex/log v1.1.2 h1:bnDuVoi+o98wOdVqfEzNDlY0tcmBia7r4YkjS9EqGYk=
-github.com/apex/log v1.1.2/go.mod h1:SyfRweFO+TlkIJ3DVizTSeI1xk7jOIIqOnUPZQTTsww=
 github.com/apex/log v1.9.0 h1:FHtw/xuaM8AgmvDDTI9fiwoAL25Sq2cxojnZICUU8l0=
 github.com/apex/log v1.9.0/go.mod h1:m82fZlWIuiWzWP04XCTXmnX0xRkYYbCdYn8jbJeLBEA=
-github.com/apex/logs v0.0.3/go.mod h1:XzxuLZ5myVHDy9SAmYpamKKRNApGj54PfYLcFrXqDwo=
 github.com/apex/logs v1.0.0/go.mod h1:XzxuLZ5myVHDy9SAmYpamKKRNApGj54PfYLcFrXqDwo=
 github.com/aphistic/golf v0.0.0-20180712155816-02c07f170c5a/go.mod h1:3NqKYiepwy8kCu4PNA+aP7WUV72eXWJeP9/r3/K9aLE=
 github.com/aphistic/sweet v0.2.0/go.mod h1:fWDlIh/isSE9n6EPsRmC0det+whmX6dJid3stzu0Xys=
@@ -177,8 +174,6 @@ github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfb
 github.com/golang/mock v1.2.0/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/mock v1.3.1 h1:qGJ6qTW+x6xX/my+8YUVl4WNpX9B7+/l2tRsHGZ7f2s=
 github.com/golang/mock v1.3.1/go.mod h1:sBzyDLLjw3U8JLTeZvSv8jJB+tU5PVekmnlKIyFUx0Y=
-github.com/golang/mock v1.4.1 h1:ocYkMQY5RrXTYgXl7ICpV0IXwlEQGwKIsery4gyXa1U=
-github.com/golang/mock v1.4.1/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt3cw=
 github.com/golang/mock v1.4.4 h1:l75CXGRSwbaYNpl/Z2X1XIIAMSCquvXgpVZDhwEIJsc=
 github.com/golang/mock v1.4.4/go.mod h1:l3mdAwkq5BuhzHwde/uurv3sEJeZMXNpwsxVWU71h+4=
 github.com/golang/protobuf v0.0.0-20161109072736-4bd1920723d7/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -390,8 +385,7 @@ github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkU
 github.com/spf13/cobra v0.0.2-0.20171109065643-2da4a54c5cee/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.3/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
-github.com/spf13/cobra v0.0.6 h1:breEStsVwemnKh2/s6gMvSdMEkwW0sK8vGStnlVBMCs=
-github.com/spf13/cobra v0.0.6/go.mod h1:/6GTrnGXV9HjY+aR4k0oJ5tcvakLuG6EuKReYlHNrgE=
+github.com/spf13/cobra v0.0.7 h1:FfTH+vuMXOas8jmfb5/M7dzEYx7LpcLb7a0LPe34uOU=
 github.com/spf13/cobra v0.0.7/go.mod h1:/6GTrnGXV9HjY+aR4k0oJ5tcvakLuG6EuKReYlHNrgE=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
@@ -412,9 +406,11 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/syndtr/gocapability v0.0.0-20170704070218-db04d3cc01c8/go.mod h1:hkRG7XYTFWNJGYcbNJQlaLq0fg1yr4J4t/NcTQtrfww=
 github.com/tj/assert v0.0.0-20171129193455-018094318fb0/go.mod h1:mZ9/Rh9oLWpLLDRpvE+3b7gP/C2YyLFYxNmcLnPTMe0=
+github.com/tj/assert v0.0.3 h1:Df/BlaZ20mq6kuai7f5z2TvPFiwC3xaWJSDQNiIS3Rk=
 github.com/tj/assert v0.0.3/go.mod h1:Ne6X72Q+TB1AteidzQncjw9PabbMp4PBMZ1k+vd1Pvk=
 github.com/tj/go-buffer v1.1.0/go.mod h1:iyiJpfFcR2B9sXu7KvjbT9fpM4mOelRSDTbntVj52Uc=
 github.com/tj/go-elastic v0.0.0-20171221160941-36157cbbebc2/go.mod h1:WjeM0Oo1eNAjXGDx2yma7uG2XoyRZTq1uv3M/o7imD0=
@@ -475,8 +471,6 @@ golang.org/x/mobile v0.0.0-20190312151609-d3739f865fa6/go.mod h1:z+o9i4GpDbdi3rU
 golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKGUJ2LatrhH/nqhxcFungHvyanc=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee h1:WG0RUwxtNT4qqaXX3DPA8zHFNm/D9xaBpxzHt1WcA/E=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
-golang.org/x/mod v0.2.0 h1:KU7oHjnv3XNWfa5COkzUifxZmxp1TyI7ImMXqFxLwvQ=
-golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0 h1:RM4zey1++hCTbCVQfnWeKs9/IEsaBLA8vTkd0WVtmH4=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20170114055629-f2499483f923/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -543,7 +537,6 @@ golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527 h1:uYVVQ9WP/Ds2ROhcaGPeIdVq0RIXVLwsHlnvJ+cT1So=
 golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.0.0-20160726164857-2910a502d2bf/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
@@ -643,6 +636,7 @@ gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.0-20200605160147-a5ece683394c h1:grhR+C34yXImVGp7EzNk+DTIk+323eIUWOmEevy6bDo=
 gopkg.in/yaml.v3 v3.0.0-20200605160147-a5ece683394c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools v2.2.0+incompatible h1:VsBPFP1AI068pPrMxtb/S8Zkgf9xEmTLJjfM+P5UIEo=
 gotest.tools v2.2.0+incompatible/go.mod h1:DsYFclhRJ6vuDpmuTbkuFWG+y2sxOXAzmJt81HFBacw=
@@ -683,8 +677,6 @@ modernc.org/golex v1.0.0/go.mod h1:b/QX9oBD/LhixY6NDh+IdGv17hgB+51fET1i2kPSmvk=
 modernc.org/mathutil v1.0.0/go.mod h1:wU0vUrJsVWBZ4P6e7xtFJEhFSNsfRLJ8H458uRjg03k=
 modernc.org/strutil v1.0.0/go.mod h1:lstksw84oURvj9y3tn8lGvRxyRC1S2+g5uuIzNfIOBs=
 modernc.org/xc v1.0.0/go.mod h1:mRNCo0bvLjGhHO9WsyuKVU4q0ceiDDDoEeWDJHrNx8I=
-rsc.io/quote/v3 v3.1.0/go.mod h1:yEA65RcK8LyAZtP9Kv3t0HmxON59tX3rD+tICJqUlj0=
-rsc.io/sampler v1.3.0/go.mod h1:T1hPZKmBbMNahiBKFy5HrXp6adAjACjK9JXDnKaTXpA=
 sigs.k8s.io/structured-merge-diff v0.0.0-20190525122527-15d366b2352e/go.mod h1:wWxsB5ozmmv/SG7nM11ayaAW51xMvak/t1r0CSlcokI=
 sigs.k8s.io/structured-merge-diff v1.0.1-0.20191108220359-b1b620dd3f06/go.mod h1:/ULNhyfzRopfcjskuui0cTITekDduZ7ycKN3oUT9R18=
 sigs.k8s.io/yaml v1.1.0/go.mod h1:UJmg0vDUVViEyp3mgSv9WPwZCDxu4rQW1olrI1uml+o=

internal/build/phase_config_provider_test.go

@@ -64,7 +64,7 @@ func testPhaseConfigProvider(t *testing.T, when spec.G, it spec.S) {
 		when("building for Windows", func() {
 			it("sets process isolation", func() {
 				fakeBuilderImage := ifakes.NewImage("fake-builder", "", nil)
-				fakeBuilderImage.SetPlatform("windows", "", "")
+				h.AssertNil(t, fakeBuilderImage.SetOS("windows"))
 				fakeBuilder, err := fakes.NewFakeBuilder(fakes.WithImage(fakeBuilderImage))
 				h.AssertNil(t, err)
 				lifecycle := newTestLifecycleExec(t, false, fakes.WithBuilder(fakeBuilder))
@@ -141,7 +141,7 @@ func testPhaseConfigProvider(t *testing.T, when spec.G, it spec.S) {
 			when("building for Windows", func() {
 				it("sets daemon access on the config", func() {
 					fakeBuilderImage := ifakes.NewImage("fake-builder", "", nil)
-					fakeBuilderImage.SetPlatform("windows", "", "")
+					h.AssertNil(t, fakeBuilderImage.SetOS("windows"))
 					fakeBuilder, err := fakes.NewFakeBuilder(fakes.WithImage(fakeBuilderImage))
 					h.AssertNil(t, err)
 					lifecycle := newTestLifecycleExec(t, false, fakes.WithBuilder(fakeBuilder))
@@ -242,7 +242,7 @@ func testPhaseConfigProvider(t *testing.T, when spec.G, it spec.S) {
 			when("building for Windows", func() {
 				it("sets root user on the config", func() {
 					fakeBuilderImage := ifakes.NewImage("fake-builder", "", nil)
-					fakeBuilderImage.SetPlatform("windows", "", "")
+					h.AssertNil(t, fakeBuilderImage.SetOS("windows"))
 					fakeBuilder, err := fakes.NewFakeBuilder(fakes.WithImage(fakeBuilderImage))
 					h.AssertNil(t, err)
 					lifecycle := newTestLifecycleExec(t, false, fakes.WithBuilder(fakeBuilder))

internal/buildpackage/builder.go

@@ -3,10 +3,12 @@ package buildpackage
 import (
 	"archive/tar"
 	"compress/gzip"
-	"context"
+	"io"
 	"io/ioutil"
 	"os"
 
+	"github.com/buildpacks/imgutil/layer"
+
 	"github.com/buildpacks/imgutil"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/empty"
@@ -15,24 +17,18 @@ import (
 	"github.com/google/go-containerregistry/pkg/v1/tarball"
 	"github.com/pkg/errors"
 
-	pubcfg "github.com/buildpacks/pack/config"
 	"github.com/buildpacks/pack/internal/archive"
 	"github.com/buildpacks/pack/internal/dist"
 	"github.com/buildpacks/pack/internal/stack"
 	"github.com/buildpacks/pack/internal/style"
 )
 
-const windowsPackageBase = "mcr.microsoft.com/windows/nanoserver:1809-amd64" // TODO: Should this be hard-coded?
-
 type ImageFactory interface {
 	NewImage(repoName string, local bool) (imgutil.Image, error)
 }
 
-type ImageFetcher interface {
-	Fetch(ctx context.Context, name string, daemon bool, pullPolicy pubcfg.PullPolicy) (imgutil.Image, error)
-}
-
 type WorkableImage interface {
+	SetOS(string) error
 	SetLabel(string, string) error
 	AddLayerWithDiffID(path, diffID string) error
 }
@@ -55,12 +51,22 @@ func (i *layoutImage) SetLabel(key string, val string) error {
 	return err
 }
 
+func (i *layoutImage) SetOS(osVal string) error {
+	configFile, err := i.ConfigFile()
+	if err != nil {
+		return err
+	}
+	configFile.OS = osVal
+	i.Image, err = mutate.ConfigFile(i.Image, configFile)
+	return err
+}
+
 func (i *layoutImage) AddLayerWithDiffID(path, _ string) error {
-	layer, err := tarball.LayerFromFile(path, tarball.WithCompressionLevel(gzip.DefaultCompression))
+	tarLayer, err := tarball.LayerFromFile(path, tarball.WithCompressionLevel(gzip.DefaultCompression))
 	if err != nil {
 		return err
 	}
-	i.Image, err = mutate.AppendLayers(i.Image, layer)
+	i.Image, err = mutate.AppendLayers(i.Image, tarLayer)
 	if err != nil {
 		return errors.Wrap(err, "add layer")
 	}
@@ -70,16 +76,12 @@ func (i *layoutImage) AddLayerWithDiffID(path, _ string) error {
 type PackageBuilder struct {
 	buildpack    dist.Buildpack
 	dependencies []dist.Buildpack
-	imageOS      string
 	imageFactory ImageFactory
-	imageFetcher ImageFetcher
 }
 
-func NewBuilder(imageOS string, imageFactory ImageFactory, imageFetcher ImageFetcher) *PackageBuilder {
+func NewBuilder(imageFactory ImageFactory) *PackageBuilder {
 	return &PackageBuilder{
-		imageOS:      imageOS,
 		imageFactory: imageFactory,
-		imageFetcher: imageFetcher,
 	}
 }
 
@@ -91,14 +93,24 @@ func (b *PackageBuilder) AddDependency(buildpack dist.Buildpack) {
 	b.dependencies = append(b.dependencies, buildpack)
 }
 
-func (b *PackageBuilder) finalizeImage(tmpDir string, image WorkableImage) error {
+func (b *PackageBuilder) finalizeImage(image WorkableImage, imageOS, tmpDir string) error {
 	if err := dist.SetLabel(image, MetadataLabel, &Metadata{
 		BuildpackInfo: b.buildpack.Descriptor().Info,
 		Stacks:        b.resolvedStacks(),
 	}); err != nil {
 		return err
 	}
 
+	if err := image.SetOS(imageOS); err != nil {
+		return err
+	}
+
+	if imageOS == "windows" {
+		if err := addWindowsShimBaseLayer(image, tmpDir); err != nil {
+			return err
+		}
+	}
+
 	bpLayers := dist.BuildpackLayers{}
 	for _, bp := range append(b.dependencies, b.buildpack) {
 		bpLayerTar, err := dist.BuildpackToLayerTar(tmpDir, bp)
@@ -128,6 +140,39 @@ func (b *PackageBuilder) finalizeImage(tmpDir string, image WorkableImage) error
 	return nil
 }
 
+func addWindowsShimBaseLayer(image WorkableImage, tmpDir string) error {
+	baseLayerFile, err := ioutil.TempFile(tmpDir, "windows-baselayer")
+	if err != nil {
+		return err
+	}
+	defer baseLayerFile.Close()
+
+	baseLayer, err := layer.WindowsBaseLayer()
+	if err != nil {
+		return err
+	}
+
+	if _, err := io.Copy(baseLayerFile, baseLayer); err != nil {
+		return err
+	}
+
+	if err := baseLayerFile.Close(); err != nil {
+		return err
+	}
+
+	baseLayerPath := baseLayerFile.Name()
+	diffID, err := dist.LayerDiffID(baseLayerPath)
+	if err != nil {
+		return err
+	}
+
+	if err := image.AddLayerWithDiffID(baseLayerPath, diffID.String()); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func (b *PackageBuilder) validate() error {
 	if b.buildpack == nil {
 		return errors.New("buildpack must be set")
@@ -159,7 +204,7 @@ func (b *PackageBuilder) resolvedStacks() []dist.Stack {
 	return stacks
 }
 
-func (b *PackageBuilder) SaveAsFile(path string) error {
+func (b *PackageBuilder) SaveAsFile(path, imageOS string) error {
 	if err := b.validate(); err != nil {
 		return err
 	}
@@ -174,7 +219,7 @@ func (b *PackageBuilder) SaveAsFile(path string) error {
 	}
 	defer os.RemoveAll(tmpDir)
 
-	if err := b.finalizeImage(tmpDir, layoutImage); err != nil {
+	if err := b.finalizeImage(layoutImage, imageOS, tmpDir); err != nil {
 		return err
 	}
 
@@ -204,26 +249,14 @@ func (b *PackageBuilder) SaveAsFile(path string) error {
 	return archive.WriteDirToTar(tw, layoutDir, "/", 0, 0, 0755, true, nil)
 }
 
-func (b *PackageBuilder) SaveAsImage(ctx context.Context, repoName string, publish bool, pullPolicy pubcfg.PullPolicy) (imgutil.Image, error) {
+func (b *PackageBuilder) SaveAsImage(repoName string, publish bool, imageOS string) (imgutil.Image, error) {
 	if err := b.validate(); err != nil {
 		return nil, err
 	}
 
-	var (
-		image imgutil.Image
-		err   error
-	)
-	if b.imageOS == "windows" {
-		image, err = b.imageFetcher.Fetch(ctx, windowsPackageBase, !publish, pullPolicy)
-		if err != nil {
-			return nil, errors.Wrapf(err, "fetching base image")
-		}
-		image.Rename(repoName)
-	} else {
-		image, err = b.imageFactory.NewImage(repoName, !publish)
-		if err != nil {
-			return nil, errors.Wrapf(err, "creating image")
-		}
+	image, err := b.imageFactory.NewImage(repoName, !publish)
+	if err != nil {
+		return nil, errors.Wrapf(err, "creating image")
 	}
 
 	tmpDir, err := ioutil.TempDir("", "package-buildpack")
@@ -232,7 +265,7 @@ func (b *PackageBuilder) SaveAsImage(ctx context.Context, repoName string, publi
 	}
 	defer os.RemoveAll(tmpDir)
 
-	if err := b.finalizeImage(tmpDir, image); err != nil {
+	if err := b.finalizeImage(image, imageOS, tmpDir); err != nil {
 		return nil, err
 	}