project: Add support for Java functions

cli/azd/pkg/project/framework_service_maven.go

@@ -2,6 +2,7 @@ package project
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -95,16 +96,36 @@ func (m *mavenProject) Package(
 	buildOutput *ServiceBuildResult,
 	progress *async.Progress[ServiceProgress],
 ) (*ServicePackageResult, error) {
-	packageDest, err := os.MkdirTemp("", "azd")
-	if err != nil {
-		return nil, fmt.Errorf("creating staging directory: %w", err)
-	}
-
 	progress.SetProgress(NewServiceProgress("Packaging maven project"))
 	if err := m.mavenCli.Package(ctx, serviceConfig.Path()); err != nil {
 		return nil, err
 	}
 
+	if serviceConfig.Host == AzureFunctionTarget {
+		if serviceConfig.OutputPath != "" {
+			// If the 'dist' property is specified, we use it directly.
+			return &ServicePackageResult{
+				Build:       buildOutput,
+				PackagePath: filepath.Join(serviceConfig.Path(), serviceConfig.OutputPath),
+			}, nil
+		}
+
+		funcAppDir, err := m.funcAppDir(ctx, serviceConfig)
+		if err != nil {
+			return nil, err
+		}
+
+		return &ServicePackageResult{
+			Build:       buildOutput,
+			PackagePath: funcAppDir,
+		}, nil
+	}
+
+	packageDest, err := os.MkdirTemp("", "azd")
+	if err != nil {
+		return nil, fmt.Errorf("creating staging directory: %w", err)
+	}
+
 	packageSrcPath := buildOutput.BuildOutputPath
 	if packageSrcPath == "" {
 		packageSrcPath = serviceConfig.Path()
@@ -153,6 +174,58 @@ func (m *mavenProject) Package(
 	}, nil
 }
 
+// funcAppDir returns the directory of the function app packaged by azure-functions-maven-plugin for the given service.
+//
+// The app is typically packaged under target/azure-functions.
+func (m *mavenProject) funcAppDir(ctx context.Context, svc *ServiceConfig) (string, error) {
+	svcPath := svc.Path()
+	// The staging directory for azure-functions-maven-plugin is target/azure-functions.
+	// It isn't configurable, but this may change in the future: https://github.com/microsoft/azure-maven-plugins/issues/1968
+	functionsStagingRel := filepath.Join("target", "azure-functions")
+	functionsStagingDir := filepath.Join(svcPath, functionsStagingRel)
+
+	// A conventional azure-functions-maven-plugin project will have the property 'functionAppName' in pom.xml,
+	// with its property value is passed to azure-functions-maven-plugin as 'appName'.
+	appName, err := m.mavenCli.GetProperty(ctx, "functionAppName", svcPath)
+	if err != nil && !errors.Is(err, maven.ErrPropertyNotFound) {
+		return "", fmt.Errorf("getting 'functionAppName' maven property: %w", err)
+	}
+
+	if appName != "" {
+		funcDir := filepath.Join(functionsStagingDir, appName)
+		if _, err := os.Stat(funcDir); err == nil {
+			return funcDir, nil
+		} else if !errors.Is(err, os.ErrNotExist) {
+			return "", fmt.Errorf("checking for function app staging directory: %w", err)
+		}
+	}
+
+	entries, err := os.ReadDir(functionsStagingDir)
+	if err != nil {
+		return "", fmt.Errorf("reading azure-functions directory: %w", err)
+	}
+
+	dirs := make([]string, 0, len(entries))
+	for _, entry := range entries {
+		if entry.IsDir() {
+			dirs = append(dirs, entry.Name())
+		}
+	}
+
+	if len(dirs) == 1 {
+		return filepath.Join(functionsStagingDir, dirs[0]), nil
+	}
+
+	for i := range dirs {
+		dirs[i] = filepath.Join(functionsStagingRel, dirs[i])
+	}
+
+	return "", fmt.Errorf(
+		//nolint:lll
+		"multiple staging directories found: %s. Specify 'dist' in azure.yaml to select a specific directory",
+		strings.Join(dirs, ", "))
+}
+
 func isSupportedJavaArchive(archiveFile string) bool {
 	ext := strings.ToLower(filepath.Ext(archiveFile))
 	return ext == ".jar" || ext == ".war" || ext == ".ear"

cli/azd/pkg/project/framework_service_maven_test.go

@@ -152,7 +152,7 @@ func Test_MavenProject(t *testing.T) {
 	})
 }
 
-func Test_MavenProject_Package(t *testing.T) {
+func Test_MavenProject_AppService_Package(t *testing.T) {
 	type args struct {
 		// service config to be packaged.
 		svc *ServiceConfig
@@ -319,6 +319,145 @@ func Test_MavenProject_Package(t *testing.T) {
 	}
 }
 
+func Test_MavenProject_FuncApp_Package(t *testing.T) {
+	tempDir := t.TempDir()
+
+	ostest.Chdir(t, tempDir)
+
+	err := os.WriteFile(getMvnwCmd(), nil, osutil.PermissionExecutableFile)
+	require.NoError(t, err)
+
+	mockContext := mocks.NewMockContext(context.Background())
+	mockContext.CommandRunner.
+		When(func(args exec.RunArgs, command string) bool {
+			return strings.Contains(command, getMvnwCmd()+" package")
+		}).
+		RespondFn(func(args exec.RunArgs) (exec.RunResult, error) {
+			return exec.NewRunResult(0, "", ""), nil
+		})
+
+	// mvnFuncAppNameProperty is the value of the maven property that holds the function app name.
+	mvnFuncAppNameProperty := ""
+	mockContext.CommandRunner.
+		When(func(args exec.RunArgs, command string) bool {
+			return strings.Contains(command, getMvnwCmd()+" help:evaluate -Dexpression=functionAppName")
+		}).
+		RespondFn(func(args exec.RunArgs) (exec.RunResult, error) {
+			if len(mvnFuncAppNameProperty) == 0 {
+				return exec.NewRunResult(0, "", ""), maven.ErrPropertyNotFound
+			}
+
+			return exec.NewRunResult(0, mvnFuncAppNameProperty, ""), nil
+		})
+
+	env := environment.New("test")
+	mavenCli := maven.NewCli(mockContext.CommandRunner)
+	javaCli := javac.NewCli(mockContext.CommandRunner)
+
+	serviceConfig := createTestServiceConfig("./src/api", AzureFunctionTarget, ServiceLanguageJava)
+	err = os.MkdirAll(serviceConfig.Path(), osutil.PermissionDirectory)
+	require.NoError(t, err)
+
+	mavenProject := NewMavenProject(env, mavenCli, javaCli)
+
+	t.Run("uses maven property functionAppName", func(t *testing.T) {
+		mvnFuncAppNameProperty = "my-function-app"
+		var svc ServiceConfig = *serviceConfig
+
+		err = os.RemoveAll(filepath.Join(svc.Path(), "target", "azure-functions"))
+		require.NoError(t, err)
+
+		err = os.MkdirAll(
+			filepath.Join(svc.Path(), "target", "azure-functions", mvnFuncAppNameProperty),
+			osutil.PermissionDirectory)
+		require.NoError(t, err)
+
+		result, err := logProgress(t, func(progress *async.Progress[ServiceProgress]) (*ServicePackageResult, error) {
+			return mavenProject.Package(
+				*mockContext.Context,
+				&svc,
+				&ServiceBuildResult{
+					BuildOutputPath: svc.Path(),
+				},
+				progress,
+			)
+		})
+
+		require.NoError(t, err)
+		require.NotNil(t, result)
+		require.Equal(t, result.PackagePath, filepath.Join(svc.Path(), "target", "azure-functions", mvnFuncAppNameProperty))
+	})
+
+	t.Run("uses target/azure-functions when maven property functionAppName not available", func(t *testing.T) {
+		mvnFuncAppNameProperty = ""
+		var svc ServiceConfig = *serviceConfig
+
+		err = os.RemoveAll(filepath.Join(svc.Path(), "target", "azure-functions"))
+		require.NoError(t, err)
+
+		err = os.MkdirAll(
+			filepath.Join(svc.Path(), "target", "azure-functions", "any"),
+			osutil.PermissionDirectory)
+		require.NoError(t, err)
+
+		result, err := logProgress(t, func(progress *async.Progress[ServiceProgress]) (*ServicePackageResult, error) {
+			return mavenProject.Package(
+				*mockContext.Context,
+				&svc,
+				&ServiceBuildResult{
+					BuildOutputPath: svc.Path(),
+				},
+				progress,
+			)
+		})
+
+		// returns single staging directory
+		require.NoError(t, err)
+		require.NotNil(t, result)
+		require.Equal(t, result.PackagePath, filepath.Join(svc.Path(), "target", "azure-functions", "any"))
+
+		// errors when multiple staging directories are found
+		err = os.MkdirAll(
+			filepath.Join(svc.Path(), "target", "azure-functions", "any2"),
+			osutil.PermissionDirectory)
+		require.NoError(t, err)
+
+		_, err = logProgress(t, func(progress *async.Progress[ServiceProgress]) (*ServicePackageResult, error) {
+			return mavenProject.Package(
+				*mockContext.Context,
+				&svc,
+				&ServiceBuildResult{
+					BuildOutputPath: svc.Path(),
+				},
+				progress,
+			)
+		})
+		require.Error(t, err)
+		require.ErrorContains(t, err, "multiple staging directories")
+	})
+
+	t.Run("uses dist specified", func(t *testing.T) {
+		mvnFuncAppNameProperty = ""
+		var svc ServiceConfig = *serviceConfig
+
+		svc.OutputPath = "my-custom-dir"
+		result, err := logProgress(t, func(progress *async.Progress[ServiceProgress]) (*ServicePackageResult, error) {
+			return mavenProject.Package(
+				*mockContext.Context,
+				&svc,
+				&ServiceBuildResult{
+					BuildOutputPath: svc.Path(),
+				},
+				progress,
+			)
+		})
+
+		require.NoError(t, err)
+		require.NotNil(t, result)
+		require.Equal(t, result.PackagePath, filepath.Join(svc.Path(), svc.OutputPath))
+	})
+}
+
 func getMvnwCmd() string {
 	if runtime.GOOS == "windows" {
 		return "mvnw.cmd"

cli/azd/pkg/tools/maven/maven.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"strings"
 	"sync"
 
 	osexec "os/exec"
@@ -212,6 +213,30 @@ func (cli *Cli) ResolveDependencies(ctx context.Context, projectPath string) err
 	return nil
 }
 
+var ErrPropertyNotFound = errors.New("property not found")
+
+func (cli *Cli) GetProperty(ctx context.Context, propertyPath string, projectPath string) (string, error) {
+	mvnCmd, err := cli.mvnCmd()
+	if err != nil {
+		return "", err
+	}
+	runArgs := exec.NewRunArgs(mvnCmd,
+		"help:evaluate",
+		// cspell: disable-next-line Dexpression and DforceStdout are maven command line arguments
+		"-Dexpression="+propertyPath, "-q", "-DforceStdout").WithCwd(projectPath)
+	res, err := cli.commandRunner.Run(ctx, runArgs)
+	if err != nil {
+		return "", fmt.Errorf("mvn help:evaluate on project '%s' failed: %w", projectPath, err)
+	}
+
+	result := strings.TrimSpace(res.Stdout)
+	if result == "null object or invalid expression" {
+		return "", ErrPropertyNotFound
+	}
+
+	return result, nil
+}
+
 func NewCli(commandRunner exec.CommandRunner) *Cli {
 	return &Cli{
 		commandRunner: commandRunner,