ninech · ctrox · Dec 14, 2023 · Dec 14, 2023
diff --git a/detect.go b/detect.go
@@ -1,7 +1,12 @@
 package static
 
 import (
+	"errors"
+	"os"
+	"path/filepath"
+
 	require "github.com/ninech/buildpack-static-require"
+	"github.com/paketo-buildpacks/libnodejs"
 	"github.com/paketo-buildpacks/packit/v2"
 	"github.com/paketo-buildpacks/packit/v2/scribe"
 )
@@ -26,6 +31,14 @@ func Detect(logger scribe.Emitter) packit.DetectFunc {
 			return packit.DetectResult{}, err
 		}
 
+		ok, nodeAppPath, err := isNodeApp(context.WorkingDir)
+		if err != nil {
+			return packit.DetectResult{}, err
+		}
+		if ok {
+			webRoot = filepath.Join(nodeAppPath, "build")
+		}
+
 		result := packit.DetectResult{
 			Plan: packit.BuildPlan{
 				Provides: []packit.BuildPlanProvision{{Name: name}},
@@ -41,3 +54,24 @@ func Detect(logger scribe.Emitter) packit.DetectFunc {
 		return result, nil
 	}
 }
+
+// isNodeApp checks if there is a package.json in the "projectPath". By
+// default that is the workspace but it could also be overridden using
+// BP_NODE_PROJECT_PATH.
+func isNodeApp(workingDir string) (bool, string, error) {
+	projectPath, err := libnodejs.FindProjectPath(workingDir)
+	if err != nil {
+		return false, "", err
+	}
+
+	if _, err := libnodejs.ParsePackageJSON(projectPath); err == nil {
+		relativePath, err := filepath.Rel(workingDir, projectPath)
+		return true, relativePath, err
+	} else {
+		if errors.Is(err, os.ErrNotExist) {
+			return false, "", nil
+		}
+
+		return false, "", err
+	}
+}
diff --git a/detect_test.go b/detect_test.go
@@ -23,6 +23,12 @@ func testDetect(t *testing.T, context spec.G, it spec.S) {
 		indexFile  = `
 <!DOCTYPE html>
 <html></html>`
+		packageJSONFile = `
+{
+	"engines": {
+		"node": "1.2.3"
+	}
+}`
 	)
 
 	it.Before(func() {
@@ -96,4 +102,55 @@ func testDetect(t *testing.T, context spec.G, it spec.S) {
 			Expect(err).To(MatchError(packit.Fail.WithMessage("no index.html found")))
 		})
 	})
+
+	context("when a package.json is present", func() {
+		it.Before(func() {
+			var err error
+			workingDir, err = os.MkdirTemp(t.TempDir(), "working-dir-*")
+			Expect(err).NotTo(HaveOccurred())
+			err = os.WriteFile(filepath.Join(workingDir, "index.html"), []byte(indexFile), os.ModePerm)
+			Expect(err).NotTo(HaveOccurred())
+			err = os.WriteFile(filepath.Join(workingDir, "package.json"), []byte(packageJSONFile), os.ModePerm)
+			Expect(err).NotTo(HaveOccurred())
+		})
+
+		it("sets the webroot accordingly", func() {
+			result, err := Detect(scribe.NewEmitter(buffer))(packit.DetectContext{
+				WorkingDir: workingDir,
+			})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result.Plan.Provides).To(ContainElement(packit.BuildPlanProvision{Name: name}))
+			Expect(result.Plan.Requires).To(ContainElement(packit.BuildPlanRequirement{
+				Name: name, Metadata: BuildPlanMetadata{WebRoot: "build"},
+			}))
+		})
+	})
+
+	context("when a package.json is present in BP_NODE_PROJECT_PATH", func() {
+		var nodeProjectPath = "node-app"
+		it.Before(func() {
+			var err error
+			workingDir, err = os.MkdirTemp(t.TempDir(), "working-dir-*")
+			Expect(err).NotTo(HaveOccurred())
+			err = os.WriteFile(filepath.Join(workingDir, "index.html"), []byte(indexFile), os.ModePerm)
+			Expect(err).NotTo(HaveOccurred())
+
+			Expect(os.MkdirAll(filepath.Join(workingDir, nodeProjectPath), os.ModePerm)).NotTo(HaveOccurred())
+			err = os.WriteFile(filepath.Join(workingDir, nodeProjectPath, "package.json"), []byte(packageJSONFile), os.ModePerm)
+			Expect(err).NotTo(HaveOccurred())
+
+			t.Setenv("BP_NODE_PROJECT_PATH", nodeProjectPath)
+		})
+
+		it("sets the webroot accordingly", func() {
+			result, err := Detect(scribe.NewEmitter(buffer))(packit.DetectContext{
+				WorkingDir: workingDir,
+			})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result.Plan.Provides).To(ContainElement(packit.BuildPlanProvision{Name: name}))
+			Expect(result.Plan.Requires).To(ContainElement(packit.BuildPlanRequirement{
+				Name: name, Metadata: BuildPlanMetadata{WebRoot: filepath.Join(nodeProjectPath, "build")},
+			}))
+		})
+	})
 }
diff --git a/go.mod b/go.mod
@@ -6,6 +6,7 @@ require (
 	github.com/BurntSushi/toml v1.3.2
 	github.com/ninech/buildpack-static-require v0.0.1
 	github.com/onsi/gomega v1.29.0
+	github.com/paketo-buildpacks/libnodejs v0.2.0
 	github.com/paketo-buildpacks/nginx v0.15.7
 	github.com/paketo-buildpacks/occam v0.17.0
 	github.com/paketo-buildpacks/packit/v2 v2.12.0

diff --git a/go.sum b/go.sum
@@ -2618,6 +2618,8 @@ github.com/otiai10/curr v1.0.0/go.mod h1:LskTG5wDwr8Rs+nNQ+1LlxRjAtTZZjtJW4rMXl6
 github.com/otiai10/mint v1.3.0/go.mod h1:F5AjcsTsWUqX+Na9fpHb52P8pcRX2CI6A3ctIT91xUo=
 github.com/otiai10/mint v1.3.1/go.mod h1:/yxELlJQ0ufhjUwhshSj+wFjZ78CnZ48/1wtmBH1OTc=
 github.com/pact-foundation/pact-go v1.0.4/go.mod h1:uExwJY4kCzNPcHRj+hCR/HBbOOIwwtUjcrb0b5/5kLM=
+github.com/paketo-buildpacks/libnodejs v0.2.0 h1:y7G6BQIeeMUnIlzREiAipQlAcaXJ82VMPldkTTiv9o4=
+github.com/paketo-buildpacks/libnodejs v0.2.0/go.mod h1:JLs6tu5TD6la8p1IKo3UYO1C93/ywGesa74FpM82wPw=
 github.com/paketo-buildpacks/nginx v0.15.7 h1:Pcs7NseRS+8RUL1HY5bkvXNp0NgPV+yDr6Ien97Im4E=
 github.com/paketo-buildpacks/nginx v0.15.7/go.mod h1:Fl+gBf4iFbY18SrmFUfN4K5jXctXOWXK++I5cPu4J1U=
 github.com/paketo-buildpacks/occam v0.17.0 h1:2Xt4Vc4MbSAsLyu+WLttd6gpR4ORsBwcoqAfWz4QaD4=

diff --git a/init_test.go b/init_test.go
@@ -8,7 +8,7 @@ import (
 )
 
 func TestUnitBuildpackStatic(t *testing.T) {
-	suite := spec.New("buildpack-static-confgen", spec.Report(report.Terminal{}), spec.Parallel())
+	suite := spec.New("buildpack-static-confgen", spec.Report(report.Terminal{}))
 	suite("Detect", testDetect)
 	suite("Build", testBuild)
 	suite.Run(t)

diff --git a/integration.json b/integration.json
@@ -3,5 +3,6 @@
     "index.docker.io/paketobuildpacks/builder-jammy-buildpackless-base:latest"
   ],
   "nginx": "github.com/paketo-buildpacks/nginx",
+  "webServers": "github.com/paketo-buildpacks/web-servers",
   "staticRequire": "github.com/ninech/buildpack-static-require"
 }
diff --git a/integration/default_test.go b/integration/default_test.go
@@ -101,5 +101,35 @@ func testDefault(t *testing.T, context spec.G, it spec.S) {
 				Eventually(container).Should(Serve(ContainSubstring("satic site served from public dir")).WithEndpoint("/index.html"))
 			})
 		})
+
+		context("when building the react_app", func() {
+			it("serves up the built index.html", func() {
+				var err error
+				source, err = occam.Source(filepath.Join("testdata", "react_app"))
+				Expect(err).NotTo(HaveOccurred())
+
+				var logs fmt.Stringer
+				image, logs, err = pack.WithNoColor().Build.
+					WithPullPolicy("never").
+					WithBuildpacks(
+						buildpack,
+						config.WebServers,
+						config.StaticRequire,
+					).
+					Execute(name, source)
+				Expect(err).NotTo(HaveOccurred(), logs.String())
+
+				container, err = docker.Container.Run.
+					WithEnv(map[string]string{"PORT": "8088"}).
+					WithPublish("8088").
+					Execute(image.ID)
+				Expect(err).ToNot(HaveOccurred())
+
+				// we expect the string %PUBLIC% to not be in the index.html
+				// anymore since npm build should take care of replacing that
+				// during build.
+				Eventually(container).Should(Serve(Not(ContainSubstring("%PUBLIC%"))).WithEndpoint("/index.html"))
+			})
+		})
 	})
 }
diff --git a/integration/init_test.go b/integration/init_test.go
@@ -27,6 +27,7 @@ var (
 
 	config struct {
 		Nginx         string `json:"nginx"`
+		WebServers    string `json:"webServers"`
 		StaticRequire string `json:"staticRequire"`
 	}
 )
@@ -67,6 +68,10 @@ func TestIntegration(t *testing.T) {
 		Execute(config.Nginx)
 	Expect(err).ToNot(HaveOccurred())
 
+	config.WebServers, err = buildpackStore.Get.
+		Execute(config.WebServers)
+	Expect(err).ToNot(HaveOccurred())
+
 	config.StaticRequire, err = buildpackStore.Get.
 		Execute(config.StaticRequire)
 	Expect(err).ToNot(HaveOccurred())

diff --git a/integration/testdata/react_app/.gitignore b/integration/testdata/react_app/.gitignore
@@ -0,0 +1,23 @@
+# See https://help.github.com/articles/ignoring-files/ for more about ignoring files.
+
+# dependencies
+/node_modules
+/.pnp
+.pnp.js
+
+# testing
+/coverage
+
+# production
+/build
+
+# misc
+.DS_Store
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*