Adding env variable for explicitly including cpython in participating during build time

README.md

@@ -2,9 +2,9 @@
 
 ## `docker.io/paketobuildpacks/node-engine`
 
-The Node Engine CNB provides the Node binary distribution.  The buildpack
+The Node Engine CNB provides the Node binary distribution. The buildpack
 installs the Node binary distribution onto the `$PATH` which makes it available
-for subsequent buildpacks and in the final running container.  Examples of
+for subsequent buildpacks and in the final running container. Examples of
 buildpacks that might use the Node binary distribution are the [NPM
 CNB](https://github.com/paketo-buildpacks/npm) and [Yarn Install
 CNB](https://github.com/paketo-buildpacks/yarn-install)
@@ -159,14 +159,34 @@ $BPL_DEBUG_PORT="9009"
 
 For more information on debugging, see [Official Documentation](https://nodejs.org/en/docs/guides/debugging-getting-started)
 
+### Include python during build process
+
+To require [python](https://github.com/paketo-buildpacks/cpython) during the build process, set the `BP_NODE_INCLUDE_BUILD_PYTHON` environment variable at build time. You can set it either directly:
+
+```shell
+pack build my-app --builder paketobuildpcks/builder-jammy-base \
+  --env BP_NODE_INCLUDE_BUILD_PYTHON=true
+```
+
+or through a [`project.toml`](https://github.com/buildpacks/spec/blob/main/extensions/project-descriptor.md) file.
+
+This is necessary for compiling native modules during `npm install` process, as `node-gyp` requires Python to complete this process.
+
+Note that the `BP_NODE_INCLUDE_BUILD_PYTHON` variable is not required in the following cases:
+
+- The [builder-jammy-full](https://github.com/paketo-buildpacks/builder-jammy-full) builder as python is already provided by the build image.
+- The UBI builders ([ubi-8-builder](https://github.com/paketo-buildpacks/builder-ubi8-base), [ubi-9-builder](https://github.com/paketo-buildpacks/ubi-9-builder), etc.), as Python is being provided by the extension during build time.
+
 ## Run Tests
 
 To run all unit tests, run:
+
 ```
 ./scripts/unit.sh
 ```
 
 To run all integration tests, run:
+
 ```
 /scripts/integration.sh
 ```

detect.go

@@ -2,7 +2,6 @@ package nodeengine
 
 import (
 	"os"
-	"os/exec"
 	"path/filepath"
 
 	"github.com/paketo-buildpacks/packit/v2"
@@ -83,10 +82,15 @@ func Detect(nvmrcParser, nodeVersionParser VersionParser) packit.DetectFunc {
 			})
 		}
 
-		targetOs := os.Getenv("CNB_TARGET_DISTRO_NAME")
-		_, pythonNotFound := exec.LookPath("python")
+		bpNodeIncludeBuildPython, bpNodeIncludeBuildPythonExists := os.LookupEnv("BP_NODE_INCLUDE_BUILD_PYTHON")
+
+		installPython := false
+		if bpNodeIncludeBuildPythonExists && (bpNodeIncludeBuildPython == "" || bpNodeIncludeBuildPython == "true") {
+			installPython = true
+		} else if bpNodeIncludeBuildPythonExists && bpNodeIncludeBuildPython == "false" {
+			installPython = false
+		}
 
-		installPython := (targetOs != "rhel" && pythonNotFound != nil)
 		if installPython {
 			requirements = append(requirements, packit.BuildPlanRequirement{
 				Name: Cpython,

detect_test.go

@@ -279,6 +279,136 @@ func testDetect(t *testing.T, context spec.G, it spec.S) {
 		})
 	})
 
+	context("when $BP_NODE_INCLUDE_BUILD_PYTHON env variable is present", func() {
+		it.After(func() {
+			os.Unsetenv("BP_NODE_INCLUDE_BUILD_PYTHON")
+		})
+
+		it("has been set to true, it should include cpython buildpack", func() {
+			os.Setenv("BP_NODE_INCLUDE_BUILD_PYTHON", "true")
+
+			result, err := detect(packit.DetectContext{
+				WorkingDir: "/working-dir",
+			})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result.Plan).To(Equal(packit.BuildPlan{
+				Provides: []packit.BuildPlanProvision{
+					{Name: nodeengine.Node},
+				},
+				Requires: []packit.BuildPlanRequirement{
+					{
+						Name: nodeengine.Cpython,
+						Metadata: nodeengine.BuildPlanMetadata{
+							Build:  true,
+							Launch: false,
+						},
+					},
+				},
+				Or: []packit.BuildPlan{
+					{
+						Provides: []packit.BuildPlanProvision{
+							{Name: nodeengine.Node},
+							{Name: nodeengine.Npm},
+						},
+						Requires: []packit.BuildPlanRequirement{
+							{
+								Name: nodeengine.Cpython,
+								Metadata: nodeengine.BuildPlanMetadata{
+									Build:  true,
+									Launch: false,
+								},
+							},
+						},
+					},
+				},
+			}))
+		})
+
+		it("has no value, it should include cpython buildpack", func() {
+			os.Setenv("BP_NODE_INCLUDE_BUILD_PYTHON", "")
+
+			result, err := detect(packit.DetectContext{
+				WorkingDir: "/working-dir",
+			})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result.Plan).To(Equal(packit.BuildPlan{
+				Provides: []packit.BuildPlanProvision{
+					{Name: nodeengine.Node},
+				},
+				Requires: []packit.BuildPlanRequirement{
+					{
+						Name: nodeengine.Cpython,
+						Metadata: nodeengine.BuildPlanMetadata{
+							Build:  true,
+							Launch: false,
+						},
+					},
+				},
+				Or: []packit.BuildPlan{
+					{
+						Provides: []packit.BuildPlanProvision{
+							{Name: nodeengine.Node},
+							{Name: nodeengine.Npm},
+						},
+						Requires: []packit.BuildPlanRequirement{
+							{
+								Name: nodeengine.Cpython,
+								Metadata: nodeengine.BuildPlanMetadata{
+									Build:  true,
+									Launch: false,
+								},
+							},
+						},
+					},
+				},
+			}))
+		})
+
+		it("has been set to false, it does not include cpython buildpack", func() {
+			os.Setenv("BP_NODE_INCLUDE_BUILD_PYTHON", "false")
+
+			result, err := detect(packit.DetectContext{
+				WorkingDir: "/working-dir",
+			})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result.Plan).To(Equal(packit.BuildPlan{
+				Provides: []packit.BuildPlanProvision{
+					{Name: nodeengine.Node},
+				},
+				Or: []packit.BuildPlan{
+					{
+						Provides: []packit.BuildPlanProvision{
+							{Name: nodeengine.Node},
+							{Name: nodeengine.Npm},
+						},
+					},
+				},
+			}))
+		})
+
+		it("has been set to random string, it does not include cpython buildpack", func() {
+			os.Setenv("BP_NODE_INCLUDE_BUILD_PYTHON", "random-string")
+
+			result, err := detect(packit.DetectContext{
+				WorkingDir: "/working-dir",
+			})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result.Plan).To(Equal(packit.BuildPlan{
+				Provides: []packit.BuildPlanProvision{
+					{Name: nodeengine.Node},
+				},
+				Or: []packit.BuildPlan{
+					{
+						Provides: []packit.BuildPlanProvision{
+							{Name: nodeengine.Node},
+							{Name: nodeengine.Npm},
+						},
+					},
+				},
+			}))
+		})
+	})
+
 	context("failure cases", func() {
 		context("when the dir specified by BP_NODE_PROJECT_PATH does not exist", func() {
 			var workingDir string

integration/inspector_test.go

@@ -52,7 +52,6 @@ func testInspector(t *testing.T, context spec.G, it spec.S) {
 		image, logs, err = pack.WithNoColor().Build.
 			WithPullPolicy("never").
 			WithBuildpacks(
-				settings.Buildpacks.Cpython.Online,
 				settings.Buildpacks.NodeEngine.Online,
 				settings.Buildpacks.Processes.Online,
 			).

integration/offline_test.go

@@ -60,7 +60,10 @@ func testOffline(t *testing.T, context spec.G, it spec.S) {
 					settings.Buildpacks.NodeEngine.Offline,
 					settings.Buildpacks.BuildPlan.Online,
 				).
-				WithEnv(map[string]string{"BP_NODE_OPTIMIZE_MEMORY": "true"}).
+				WithEnv(map[string]string{
+					"BP_NODE_OPTIMIZE_MEMORY":      "true",
+					"BP_NODE_INCLUDE_BUILD_PYTHON": "true",
+				}).
 				WithNetwork("none").
 				Execute(name, source)
 

integration/openssl_test.go

@@ -67,7 +67,6 @@ func testOpenSSL(t *testing.T, context spec.G, it spec.S) {
 
 				image, logs, err = pack.WithNoColor().Build.
 					WithBuildpacks(
-						settings.Buildpacks.Cpython.Online,
 						settings.Buildpacks.NodeEngine.Online,
 						settings.Buildpacks.BuildPlan.Online,
 					).
@@ -107,7 +106,6 @@ func testOpenSSL(t *testing.T, context spec.G, it spec.S) {
 
 				image, logs, err = pack.WithNoColor().Build.
 					WithBuildpacks(
-						settings.Buildpacks.Cpython.Online,
 						settings.Buildpacks.NodeEngine.Online,
 						settings.Buildpacks.BuildPlan.Online,
 					).

integration/optimize_memory_test.go

@@ -53,7 +53,6 @@ func testOptimizeMemory(t *testing.T, context spec.G, it spec.S) {
 		image, logs, err = pack.WithNoColor().Build.
 			WithPullPolicy("never").
 			WithBuildpacks(
-				settings.Buildpacks.Cpython.Online,
 				settings.Buildpacks.NodeEngine.Online,
 				settings.Buildpacks.Processes.Online,
 			).

integration/project_path_test.go

@@ -60,7 +60,6 @@ func testProjectPath(t *testing.T, context spec.G, it spec.S) {
 			image, logs, err = pack.WithNoColor().Build.
 				WithPullPolicy("never").
 				WithBuildpacks(
-					settings.Buildpacks.Cpython.Online,
 					settings.Buildpacks.NodeEngine.Online,
 					settings.Buildpacks.BuildPlan.Online,
 				).

integration/provides_test.go

@@ -55,7 +55,6 @@ func testProvides(t *testing.T, context spec.G, it spec.S) {
 			image, logs, err = pack.WithNoColor().Build.
 				WithPullPolicy("never").
 				WithBuildpacks(
-					settings.Buildpacks.Cpython.Online,
 					settings.Buildpacks.NodeEngine.Online,
 					settings.Buildpacks.BuildPlan.Online,
 				).

integration/reuse_layer_rebuild_test.go

@@ -72,7 +72,6 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 			firstImage, logs, err = pack.WithNoColor().Build.
 				WithPullPolicy("never").
 				WithBuildpacks(
-					settings.Buildpacks.Cpython.Online,
 					settings.Buildpacks.NodeEngine.Online,
 					settings.Buildpacks.BuildPlan.Online,
 				).
@@ -81,10 +80,9 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 
 			imageIDs[firstImage.ID] = struct{}{}
 
-
-			Expect(firstImage.Buildpacks).To(HaveLen(3))
-			Expect(firstImage.Buildpacks[1].Key).To(Equal(settings.Buildpack.ID))
-			Expect(firstImage.Buildpacks[1].Layers).To(HaveKey("node"))
+			Expect(firstImage.Buildpacks).To(HaveLen(2))
+			Expect(firstImage.Buildpacks[0].Key).To(Equal(settings.Buildpack.ID))
+			Expect(firstImage.Buildpacks[0].Layers).To(HaveKey("node"))
 
 			Expect(logs).To(ContainLines(
 				fmt.Sprintf("%s 1.2.3", settings.Buildpack.Name),
@@ -139,7 +137,6 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 			secondImage, logs, err = pack.WithNoColor().Build.
 				WithPullPolicy("never").
 				WithBuildpacks(
-					settings.Buildpacks.Cpython.Online,
 					settings.Buildpacks.NodeEngine.Online,
 					settings.Buildpacks.BuildPlan.Online,
 				).
@@ -148,9 +145,9 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 
 			imageIDs[secondImage.ID] = struct{}{}
 
-			Expect(secondImage.Buildpacks).To(HaveLen(3))
-			Expect(secondImage.Buildpacks[1].Key).To(Equal(settings.Buildpack.ID))
-			Expect(secondImage.Buildpacks[1].Layers).To(HaveKey("node"))
+			Expect(secondImage.Buildpacks).To(HaveLen(2))
+			Expect(secondImage.Buildpacks[0].Key).To(Equal(settings.Buildpack.ID))
+			Expect(secondImage.Buildpacks[0].Layers).To(HaveKey("node"))
 
 			Expect(logs).To(ContainLines(
 				fmt.Sprintf("%s 1.2.3", settings.Buildpack.Name),
@@ -184,8 +181,7 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 			Expect(err).NotTo(HaveOccurred())
 			Expect(content).To(ContainSubstring("hello world"))
 
-			Expect(secondImage.Buildpacks[0].Layers["cpython"].SHA).To(Equal(firstImage.Buildpacks[0].Layers["cpython"].SHA))
-			Expect(secondImage.Buildpacks[1].Layers["node"].SHA).To(Equal(firstImage.Buildpacks[1].Layers["node"].SHA))
+			Expect(secondImage.Buildpacks[0].Layers["node"].SHA).To(Equal(firstImage.Buildpacks[0].Layers["node"].SHA))
 		})
 	})
 
@@ -207,7 +203,6 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 			firstImage, logs, err = pack.WithNoColor().Build.
 				WithPullPolicy("never").
 				WithBuildpacks(
-					settings.Buildpacks.Cpython.Online,
 					settings.Buildpacks.NodeEngine.Online,
 					settings.Buildpacks.BuildPlan.Online,
 				).
@@ -217,9 +212,9 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 
 			imageIDs[firstImage.ID] = struct{}{}
 
-			Expect(firstImage.Buildpacks).To(HaveLen(3))
-			Expect(firstImage.Buildpacks[1].Key).To(Equal(settings.Buildpack.ID))
-			Expect(firstImage.Buildpacks[1].Layers).To(HaveKey("node"))
+			Expect(firstImage.Buildpacks).To(HaveLen(2))
+			Expect(firstImage.Buildpacks[0].Key).To(Equal(settings.Buildpack.ID))
+			Expect(firstImage.Buildpacks[0].Layers).To(HaveKey("node"))
 
 			Expect(logs).To(ContainLines(
 				fmt.Sprintf("%s 1.2.3", settings.Buildpack.Name),
@@ -275,7 +270,6 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 			secondImage, logs, err = pack.WithNoColor().Build.
 				WithPullPolicy("never").
 				WithBuildpacks(
-					settings.Buildpacks.Cpython.Online,
 					settings.Buildpacks.NodeEngine.Online,
 					settings.Buildpacks.BuildPlan.Online,
 				).
@@ -285,9 +279,9 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 
 			imageIDs[secondImage.ID] = struct{}{}
 
-			Expect(secondImage.Buildpacks).To(HaveLen(3))
-			Expect(secondImage.Buildpacks[1].Key).To(Equal(settings.Buildpack.ID))
-			Expect(secondImage.Buildpacks[1].Layers).To(HaveKey("node"))
+			Expect(secondImage.Buildpacks).To(HaveLen(2))
+			Expect(secondImage.Buildpacks[0].Key).To(Equal(settings.Buildpack.ID))
+			Expect(secondImage.Buildpacks[0].Layers).To(HaveKey("node"))
 
 			Expect(logs).To(ContainLines(
 				fmt.Sprintf("%s 1.2.3", settings.Buildpack.Name),
@@ -347,7 +341,7 @@ func testReusingLayerRebuild(t *testing.T, context spec.G, it spec.S) {
 			Expect(err).NotTo(HaveOccurred())
 			Expect(content).To(ContainSubstring("hello world"))
 
-			Expect(secondImage.Buildpacks[1].Layers["node"].SHA).NotTo(Equal(firstImage.Buildpacks[1].Layers["node"].SHA))
+			Expect(secondImage.Buildpacks[0].Layers["node"].SHA).NotTo(Equal(firstImage.Buildpacks[0].Layers["node"].SHA))
 		})
 	})
 }