First look for databricks.yml before falling back to bundle.yml (#580)

## Changes
* Add support for using `databricks.yml` as config file. If
`databricks.yml` is not found then falling back to `bundle.yml` for
backwards compatibility.
* Add support for `.yaml` extension.
* Give an error when more than one config file is found

## Tests
* added unit test
* manual testing the different cases

---------

Co-authored-by: Pieter Noordhuis <pieter.noordhuis@databricks.com>

bundle/bundle.go

@@ -45,7 +45,11 @@ type Bundle struct {
 
 func Load(path string) (*Bundle, error) {
 	bundle := &Bundle{}
-	err := bundle.Config.Load(filepath.Join(path, config.FileName))
+	configFile, err := config.FileNames.FindInPath(path)
+	if err != nil {
+		return nil, err
+	}
+	err = bundle.Config.Load(configFile)
 	if err != nil {
 		return nil, err
 	}

bundle/bundle_test.go

@@ -23,7 +23,7 @@ func TestLoadExists(t *testing.T) {
 
 func TestBundleCacheDir(t *testing.T) {
 	projectDir := t.TempDir()
-	f1, err := os.Create(filepath.Join(projectDir, "bundle.yml"))
+	f1, err := os.Create(filepath.Join(projectDir, "databricks.yml"))
 	require.NoError(t, err)
 	f1.Close()
 
@@ -47,7 +47,7 @@ func TestBundleCacheDir(t *testing.T) {
 func TestBundleCacheDirOverride(t *testing.T) {
 	projectDir := t.TempDir()
 	bundleTmpDir := t.TempDir()
-	f1, err := os.Create(filepath.Join(projectDir, "bundle.yml"))
+	f1, err := os.Create(filepath.Join(projectDir, "databricks.yml"))
 	require.NoError(t, err)
 	f1.Close()
 

bundle/config/mutator/process_root_includes.go

@@ -27,8 +27,10 @@ func (m *processRootIncludes) Apply(ctx context.Context, b *bundle.Bundle) error
 	var out []bundle.Mutator
 
 	// Map with files we've already seen to avoid loading them twice.
-	var seen = map[string]bool{
-		config.FileName: true,
+	var seen = map[string]bool{}
+
+	for _, file := range config.FileNames {
+		seen[file] = true
 	}
 
 	// Maintain list of files in order of files being loaded.

bundle/config/mutator/process_root_includes_test.go

@@ -61,7 +61,7 @@ func TestProcessRootIncludesSingleGlob(t *testing.T) {
 		},
 	}
 
-	touch(t, bundle.Config.Path, "bundle.yml")
+	touch(t, bundle.Config.Path, "databricks.yml")
 	touch(t, bundle.Config.Path, "a.yml")
 	touch(t, bundle.Config.Path, "b.yml")
 

bundle/config/root.go

@@ -11,12 +11,39 @@ import (
 	"github.com/imdario/mergo"
 )
 
-// FileName is the name of bundle configuration file.
-const FileName = "bundle.yml"
+type ConfigFileNames []string
+
+// FileNames contains allowed names of bundle configuration files.
+var FileNames = ConfigFileNames{"databricks.yml", "databricks.yaml", "bundle.yml", "bundle.yaml"}
+
+func (c ConfigFileNames) FindInPath(path string) (string, error) {
+	result := ""
+	var firstErr error
+
+	for _, file := range c {
+		filePath := filepath.Join(path, file)
+		_, err := os.Stat(filePath)
+		if err == nil {
+			if result != "" {
+				return "", fmt.Errorf("multiple bundle root configuration files found in %s", path)
+			}
+			result = filePath
+		} else {
+			if firstErr == nil {
+				firstErr = err
+			}
+		}
+	}
+
+	if result == "" {
+		return "", firstErr
+	}
+	return result, nil
+}
 
 type Root struct {
 	// Path contains the directory path to the root of the bundle.
-	// It is set when loading `bundle.yml`.
+	// It is set when loading `databricks.yml`.
 	Path string `json:"-" bundle:"readonly"`
 
 	// Contains user defined variables
@@ -27,7 +54,7 @@ type Root struct {
 	Bundle Bundle `json:"bundle"`
 
 	// Include specifies a list of patterns of file names to load and
-	// merge into the this configuration. If not set in `bundle.yml`,
+	// merge into the this configuration. If not set in `databricks.yml`,
 	// it defaults to loading `*.yml` and `*/*.yml`.
 	//
 	// Also see [mutator.DefineDefaultInclude].
@@ -62,7 +89,10 @@ func Load(path string) (*Root, error) {
 
 	// If we were given a directory, assume this is the bundle root.
 	if stat.IsDir() {
-		path = filepath.Join(path, FileName)
+		path, err = FileNames.FindInPath(path)
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	if err := r.Load(path); err != nil {

bundle/config/root_test.go

@@ -2,7 +2,11 @@ package config
 
 import (
 	"encoding/json"
+	"os"
+	"path/filepath"
 	"reflect"
+	"runtime"
+	"strings"
 	"testing"
 
 	"github.com/databricks/cli/bundle/config/variable"
@@ -26,7 +30,7 @@ func TestRootMarshalUnmarshal(t *testing.T) {
 
 func TestRootLoad(t *testing.T) {
 	root := &Root{}
-	err := root.Load("../tests/basic/bundle.yml")
+	err := root.Load("../tests/basic/databricks.yml")
 	require.NoError(t, err)
 	assert.Equal(t, "basic", root.Bundle.Name)
 }
@@ -78,13 +82,13 @@ func TestRootMergeMap(t *testing.T) {
 
 func TestDuplicateIdOnLoadReturnsError(t *testing.T) {
 	root := &Root{}
-	err := root.Load("./testdata/duplicate_resource_names_in_root/bundle.yml")
-	assert.ErrorContains(t, err, "multiple resources named foo (job at ./testdata/duplicate_resource_names_in_root/bundle.yml, pipeline at ./testdata/duplicate_resource_names_in_root/bundle.yml)")
+	err := root.Load("./testdata/duplicate_resource_names_in_root/databricks.yml")
+	assert.ErrorContains(t, err, "multiple resources named foo (job at ./testdata/duplicate_resource_names_in_root/databricks.yml, pipeline at ./testdata/duplicate_resource_names_in_root/databricks.yml)")
 }
 
 func TestDuplicateIdOnMergeReturnsError(t *testing.T) {
 	root := &Root{}
-	err := root.Load("./testdata/duplicate_resource_name_in_subconfiguration/bundle.yml")
+	err := root.Load("./testdata/duplicate_resource_name_in_subconfiguration/databricks.yml")
 	require.NoError(t, err)
 
 	other := &Root{}
@@ -92,7 +96,7 @@ func TestDuplicateIdOnMergeReturnsError(t *testing.T) {
 	require.NoError(t, err)
 
 	err = root.Merge(other)
-	assert.ErrorContains(t, err, "multiple resources named foo (job at ./testdata/duplicate_resource_name_in_subconfiguration/bundle.yml, pipeline at ./testdata/duplicate_resource_name_in_subconfiguration/resources.yml)")
+	assert.ErrorContains(t, err, "multiple resources named foo (job at ./testdata/duplicate_resource_name_in_subconfiguration/databricks.yml, pipeline at ./testdata/duplicate_resource_name_in_subconfiguration/resources.yml)")
 }
 
 func TestInitializeVariables(t *testing.T) {
@@ -163,3 +167,62 @@ func TestRootMergeEnvironmentWithMode(t *testing.T) {
 	require.NoError(t, root.MergeEnvironment(env))
 	assert.Equal(t, Development, root.Bundle.Mode)
 }
+
+func TestConfigFileNames_FindInPath(t *testing.T) {
+	testCases := []struct {
+		name     string
+		files    []string
+		expected string
+		err      string
+	}{
+		{
+			name:     "file found",
+			files:    []string{"databricks.yml"},
+			expected: "BASE/databricks.yml",
+			err:      "",
+		},
+		{
+			name:     "file found",
+			files:    []string{"bundle.yml"},
+			expected: "BASE/bundle.yml",
+			err:      "",
+		},
+		{
+			name:     "multiple files found",
+			files:    []string{"databricks.yaml", "bundle.yml"},
+			expected: "",
+			err:      "multiple bundle root configuration files found",
+		},
+		{
+			name:     "file not found",
+			files:    []string{},
+			expected: "",
+			err:      "no such file or directory",
+		},
+	}
+
+	if runtime.GOOS == "windows" {
+		testCases[3].err = "The system cannot find the file specified."
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			projectDir := t.TempDir()
+			for _, file := range tc.files {
+				f1, _ := os.Create(filepath.Join(projectDir, file))
+				f1.Close()
+			}
+
+			result, err := FileNames.FindInPath(projectDir)
+
+			expected := strings.Replace(tc.expected, "BASE/", projectDir+string(os.PathSeparator), 1)
+			assert.Equal(t, expected, result)
+
+			if tc.err != "" {
+				assert.ErrorContains(t, err, tc.err)
+			} else {
+				assert.NoError(t, err)
+			}
+		})
+	}
+}

bundle/root.go

@@ -36,12 +36,16 @@ func getRootWithTraversal() (string, error) {
 	if err != nil {
 		return "", err
 	}
-	path, err := folders.FindDirWithLeaf(wd, config.FileName)
-	if err != nil {
-		return "", fmt.Errorf(`unable to locate bundle root: %s not found`, config.FileName)
-	}
+
+	for _, file := range config.FileNames {
+		path, err := folders.FindDirWithLeaf(wd, file)
+		if err == nil {
 			return path, nil
 		}
+	}
+
+	return "", fmt.Errorf(`unable to locate bundle root: %s not found`, config.FileNames[0])
+}
 
 // mustGetRoot returns a bundle root or an error if one cannot be found.
 func mustGetRoot() (string, error) {

bundle/root_test.go

@@ -76,8 +76,8 @@ func TestRootLookup(t *testing.T) {
 
 	chdir(t, t.TempDir())
 
-	// Create bundle.yml file.
-	f, err := os.Create(config.FileName)
+	// Create databricks.yml file.
+	f, err := os.Create(config.FileNames[0])
 	require.NoError(t, err)
 	defer f.Close()
 

bundle/tests/conflicting_resource_ids_test.go

@@ -14,7 +14,7 @@ import (
 
 func TestConflictingResourceIdsNoSubconfig(t *testing.T) {
 	_, err := bundle.Load("./conflicting_resource_ids/no_subconfigurations")
-	bundleConfigPath := filepath.FromSlash("conflicting_resource_ids/no_subconfigurations/bundle.yml")
+	bundleConfigPath := filepath.FromSlash("conflicting_resource_ids/no_subconfigurations/databricks.yml")
 	assert.ErrorContains(t, err, fmt.Sprintf("multiple resources named foo (job at %s, pipeline at %s)", bundleConfigPath, bundleConfigPath))
 }
 
@@ -22,7 +22,7 @@ func TestConflictingResourceIdsOneSubconfig(t *testing.T) {
 	b, err := bundle.Load("./conflicting_resource_ids/one_subconfiguration")
 	require.NoError(t, err)
 	err = bundle.Apply(context.Background(), b, bundle.Seq(mutator.DefaultMutators()...))
-	bundleConfigPath := filepath.FromSlash("conflicting_resource_ids/one_subconfiguration/bundle.yml")
+	bundleConfigPath := filepath.FromSlash("conflicting_resource_ids/one_subconfiguration/databricks.yml")
 	resourcesConfigPath := filepath.FromSlash("conflicting_resource_ids/one_subconfiguration/resources.yml")
 	assert.ErrorContains(t, err, fmt.Sprintf("multiple resources named foo (job at %s, pipeline at %s)", bundleConfigPath, resourcesConfigPath))
 }

bundle/tests/job_and_pipeline_test.go

@@ -15,7 +15,7 @@ func TestJobAndPipelineDevelopment(t *testing.T) {
 	assert.Len(t, b.Config.Resources.Pipelines, 1)
 
 	p := b.Config.Resources.Pipelines["nyc_taxi_pipeline"]
-	assert.Equal(t, "job_and_pipeline/bundle.yml", filepath.ToSlash(p.ConfigFilePath))
+	assert.Equal(t, "job_and_pipeline/databricks.yml", filepath.ToSlash(p.ConfigFilePath))
 	assert.Equal(t, b.Config.Bundle.Mode, config.Development)
 	assert.True(t, p.Development)
 	require.Len(t, p.Libraries, 1)
@@ -29,7 +29,7 @@ func TestJobAndPipelineStaging(t *testing.T) {
 	assert.Len(t, b.Config.Resources.Pipelines, 1)
 
 	p := b.Config.Resources.Pipelines["nyc_taxi_pipeline"]
-	assert.Equal(t, "job_and_pipeline/bundle.yml", filepath.ToSlash(p.ConfigFilePath))
+	assert.Equal(t, "job_and_pipeline/databricks.yml", filepath.ToSlash(p.ConfigFilePath))
 	assert.False(t, p.Development)
 	require.Len(t, p.Libraries, 1)
 	assert.Equal(t, "./dlt/nyc_taxi_loader", p.Libraries[0].Notebook.Path)
@@ -42,14 +42,14 @@ func TestJobAndPipelineProduction(t *testing.T) {
 	assert.Len(t, b.Config.Resources.Pipelines, 1)
 
 	p := b.Config.Resources.Pipelines["nyc_taxi_pipeline"]
-	assert.Equal(t, "job_and_pipeline/bundle.yml", filepath.ToSlash(p.ConfigFilePath))
+	assert.Equal(t, "job_and_pipeline/databricks.yml", filepath.ToSlash(p.ConfigFilePath))
 	assert.False(t, p.Development)
 	require.Len(t, p.Libraries, 1)
 	assert.Equal(t, "./dlt/nyc_taxi_loader", p.Libraries[0].Notebook.Path)
 	assert.Equal(t, "nyc_taxi_production", p.Target)
 
 	j := b.Config.Resources.Jobs["pipeline_schedule"]
-	assert.Equal(t, "job_and_pipeline/bundle.yml", filepath.ToSlash(j.ConfigFilePath))
+	assert.Equal(t, "job_and_pipeline/databricks.yml", filepath.ToSlash(j.ConfigFilePath))
 	assert.Equal(t, "Daily refresh of production pipeline", j.Name)
 	require.Len(t, j.Tasks, 1)
 	assert.NotEmpty(t, j.Tasks[0].PipelineTask.PipelineId)

cmd/sync/sync.go

@@ -72,7 +72,7 @@ var syncCmd = &cobra.Command{
 
 		//
 		// To be uncommented and used once our VS Code extension is bundle aware.
-		// Until then, this could interfere with extension usage where a `bundle.yml` file is present.
+		// Until then, this could interfere with extension usage where a `databricks.yml` file is present.
 		// See https://github.com/databricks/cli/pull/207.
 		//
 		// b := bundle.GetOrNil(cmd.Context())