feat(cnbBuild): preserve maven test results in the workspace (#3429)

Co-authored-by: Pavel Busko <pavel.busko@sap.com>
Co-authored-by: Ralf Pannemans <ralf.pannemans@sap.com>

cmd/cnbBuild.go

@@ -98,14 +98,6 @@ func isIgnored(find string, include, exclude *ignore.GitIgnore) bool {
 	return false
 }
 
-func isDir(path string) (bool, error) {
-	info, err := os.Stat(path)
-	if err != nil {
-		return false, err
-	}
-	return info.IsDir(), nil
-}
-
 func isBuilder(utils cnbutils.BuildUtils) error {
 	exists, err := utils.FileExists(creatorPath)
 	if err != nil {
@@ -163,7 +155,7 @@ func copyProject(source, target string, include, exclude *ignore.GitIgnore, util
 		}
 		if !isIgnored(relPath, include, exclude) {
 			target := path.Join(target, strings.ReplaceAll(sourceFile, source, ""))
-			dir, err := isDir(sourceFile)
+			dir, err := utils.DirExists(sourceFile)
 			if err != nil {
 				log.SetErrorCategory(log.ErrorBuild)
 				return errors.Wrapf(err, "Checking file info '%s' failed", target)
@@ -221,6 +213,27 @@ func prepareDockerConfig(source string, utils cnbutils.BuildUtils) (string, erro
 	return source, nil
 }
 
+func linkTargetFolder(utils cnbutils.BuildUtils, source, target string) error {
+	var err error
+	linkPath := filepath.Join(target, "target")
+	targetPath := filepath.Join(source, "target")
+	if ok, _ := utils.DirExists(targetPath); !ok {
+		err = utils.MkdirAll(targetPath, os.ModePerm)
+		if err != nil {
+			return err
+		}
+	}
+
+	if ok, _ := utils.DirExists(linkPath); ok {
+		err = utils.RemoveAll(linkPath)
+		if err != nil {
+			return err
+		}
+	}
+
+	return utils.Symlink(targetPath, linkPath)
+}
+
 func (c *cnbBuildOptions) mergeEnvVars(vars map[string]interface{}) {
 	if c.BuildEnvVars == nil {
 		c.BuildEnvVars = vars
@@ -302,20 +315,23 @@ func runCnbBuild(config *cnbBuildOptions, telemetryData *telemetry.CustomData, u
 	}
 
 	target := "/workspace"
-	source, err := utils.Getwd()
+	pwd, err := utils.Getwd()
 	if err != nil {
 		log.SetErrorCategory(log.ErrorBuild)
 		return errors.Wrap(err, "failed to get current working directory")
 	}
 
+	var source string
 	if len(config.Path) > 0 {
 		source = config.Path
+	} else {
+		source = pwd
 	}
 
-	dir, err := isDir(source)
+	dir, err := utils.DirExists(source)
 	if err != nil {
 		log.SetErrorCategory(log.ErrorBuild)
-		return errors.Wrapf(err, "Checking file info '%s' failed", target)
+		return errors.Wrapf(err, "Checking file info '%s' failed", source)
 	}
 
 	if dir {
@@ -332,6 +348,14 @@ func runCnbBuild(config *cnbBuildOptions, telemetryData *telemetry.CustomData, u
 		}
 	}
 
+	if ok, _ := utils.FileExists(filepath.Join(target, "pom.xml")); ok {
+		err = linkTargetFolder(utils, pwd, target)
+		if err != nil {
+			log.SetErrorCategory(log.ErrorBuild)
+			return err
+		}
+	}
+
 	metadata.WriteProjectMetadata(GeneralConfig.EnvRootPath, utils)
 
 	var buildpacksPath = "/cnb/buildpacks"

cmd/cnbBuild_test.go

@@ -192,6 +192,55 @@ func TestRunCnbBuild(t *testing.T) {
 		assert.Contains(t, runner.Calls[0].Params, fmt.Sprintf("%s/%s:3.1.5", registry, config.ContainerImageName))
 	})
 
+	t.Run("pom.xml exists (symlink for the target folder)", func(t *testing.T) {
+		t.Parallel()
+		config := cnbBuildOptions{
+			ContainerImageName:   "my-image",
+			ContainerImageTag:    "3.1.5",
+			ContainerRegistryURL: "some-registry",
+			DockerConfigJSON:     "/path/to/config.json",
+		}
+
+		utils := newCnbBuildTestsUtils()
+		utils.FilesMock.CurrentDir = "/jenkins"
+		utils.FilesMock.AddDir("/jenkins")
+		utils.FilesMock.AddFile(config.DockerConfigJSON, []byte(`{"auths":{"my-registry":{"auth":"dXNlcjpwYXNz"}}}`))
+		utils.FilesMock.AddFile("/workspace/pom.xml", []byte("test"))
+		addBuilderFiles(&utils)
+
+		err := runCnbBuild(&config, &telemetry.CustomData{}, &utils, &cnbBuildCommonPipelineEnvironment{}, &piperhttp.Client{})
+		assert.NoError(t, err)
+
+		runner := utils.ExecMockRunner
+		assertLifecycleCalls(t, runner)
+
+		assert.True(t, utils.FilesMock.HasCreatedSymlink("/jenkins/target", "/workspace/target"))
+	})
+
+	t.Run("no pom.xml exists (no symlink for the target folder)", func(t *testing.T) {
+		t.Parallel()
+		config := cnbBuildOptions{
+			ContainerImageName:   "my-image",
+			ContainerImageTag:    "3.1.5",
+			ContainerRegistryURL: "some-registry",
+			DockerConfigJSON:     "/path/to/config.json",
+		}
+
+		utils := newCnbBuildTestsUtils()
+		utils.FilesMock.CurrentDir = "/jenkins"
+		utils.FilesMock.AddDir("/jenkins")
+		utils.FilesMock.AddFile(config.DockerConfigJSON, []byte(`{"auths":{"my-registry":{"auth":"dXNlcjpwYXNz"}}}`))
+		addBuilderFiles(&utils)
+
+		err := runCnbBuild(&config, &telemetry.CustomData{}, &utils, &cnbBuildCommonPipelineEnvironment{}, &piperhttp.Client{})
+		assert.NoError(t, err)
+
+		runner := utils.ExecMockRunner
+		assertLifecycleCalls(t, runner)
+
+		assert.False(t, utils.FilesMock.HasCreatedSymlink("/jenkins/target", "/workspace/target"))
+	})
+
 	t.Run("error case: Invalid DockerConfigJSON file", func(t *testing.T) {
 		t.Parallel()
 		commonPipelineEnvironment := cnbBuildCommonPipelineEnvironment{}