Error out if notebook file does not exist locally (#261)

Adds check for whether file exists locally

case 1: local (relative) file does not exist
```
    foo:
      name: "[job-output] test-job by shreyas"

      tasks:
        - task_key: my_notebook_task
          existing_cluster_id: ***
          notebook_task:
            notebook_path: "./doesnotexist"
```
output:
```
shreyas.goenka@THW32HFW6T job-output % bricks bundle deploy
Error: notebook ./doesnotexist not found. Error: open /Users/shreyas.goenka/projects/job-output/doesnotexist: no such file or directory
```


case 2: remote (absolute) file does not exist
```
    foo:
      name: "[job-output] test-job by shreyas"

      tasks:
        - task_key: my_notebook_task
          existing_cluster_id: ***
          notebook_task:
            notebook_path: "/Users/shreyas.goenka@databricks.com/doesnotexist"
```

output:
```
shreyas.goenka@THW32HFW6T job-output % bricks bundle deploy
shreyas.goenka@THW32HFW6T job-output % bricks bundle run foo
Error: failed to reach TERMINATED or SKIPPED, got INTERNAL_ERROR: Task my_notebook_task failed with message: Notebook not found: /Users/shreyas.goenka@databricks.com/doesnotexist. This caused all downstream tasks to get skipped.
```

case 3: remote exists
Successful deploy and run

bundle/config/mutator/translate_notebook_paths.go

@@ -26,6 +26,10 @@ func (m *translateNotebookPaths) Name() string {
 }
 
 func (m *translateNotebookPaths) rewritePath(b *bundle.Bundle, p *string) error {
+	// We assume absolute paths point to a location in the workspace
+	if path.IsAbs(*p) {
+		return nil
+	}
 	relPath := path.Clean(*p)
 	if interp, ok := m.seen[relPath]; ok {
 		*p = interp
@@ -34,14 +38,12 @@ func (m *translateNotebookPaths) rewritePath(b *bundle.Bundle, p *string) error
 
 	absPath := filepath.Join(b.Config.Path, relPath)
 	nb, _, err := notebook.Detect(absPath)
-	if err != nil {
-		// Ignore if this file doesn't exist. Maybe it's an absolute workspace path?
 	if os.IsNotExist(err) {
-			return nil
+		return fmt.Errorf("notebook %s not found: %w", *p, err)
 	}
+	if err != nil {
 		return fmt.Errorf("unable to determine if %s is a notebook: %w", relPath, err)
 	}
-
 	if !nb {
 		return fmt.Errorf("file at %s is not a notebook", relPath)
 	}

bundle/config/mutator/translate_notebook_paths_test.go

@@ -43,7 +43,7 @@ func TestNotebookPaths(t *testing.T) {
 								},
 								{
 									NotebookTask: &jobs.NotebookTask{
-										NotebookPath: "./doesnt_exist.py",
+										NotebookPath: "/Users/jane.doe@databricks.com/doesnt_exist.py",
 									},
 								},
 								{
@@ -71,7 +71,7 @@ func TestNotebookPaths(t *testing.T) {
 								},
 								{
 									Notebook: &pipelines.NotebookLibrary{
-										Path: "./doesnt_exist.py",
+										Path: "/Users/jane.doe@databricks.com/doesnt_exist.py",
 									},
 								},
 								{
@@ -101,7 +101,7 @@ func TestNotebookPaths(t *testing.T) {
 	)
 	assert.Equal(
 		t,
-		"./doesnt_exist.py",
+		"/Users/jane.doe@databricks.com/doesnt_exist.py",
 		bundle.Config.Resources.Jobs["job"].Tasks[1].NotebookTask.NotebookPath,
 	)
 	assert.Equal(
@@ -118,7 +118,7 @@ func TestNotebookPaths(t *testing.T) {
 	)
 	assert.Equal(
 		t,
-		"./doesnt_exist.py",
+		"/Users/jane.doe@databricks.com/doesnt_exist.py",
 		bundle.Config.Resources.Pipelines["pipeline"].Libraries[1].Notebook.Path,
 	)
 	assert.Equal(
@@ -127,3 +127,59 @@ func TestNotebookPaths(t *testing.T) {
 		bundle.Config.Resources.Pipelines["pipeline"].Libraries[2].Notebook.Path,
 	)
 }
+
+func TestJobNotebookDoesNotExistError(t *testing.T) {
+	dir := t.TempDir()
+
+	bundle := &bundle.Bundle{
+		Config: config.Root{
+			Path: dir,
+			Resources: config.Resources{
+				Jobs: map[string]*resources.Job{
+					"job": {
+						JobSettings: &jobs.JobSettings{
+							Tasks: []jobs.JobTaskSettings{
+								{
+									NotebookTask: &jobs.NotebookTask{
+										NotebookPath: "./doesnt_exist.py",
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+
+	_, err := mutator.TranslateNotebookPaths().Apply(context.Background(), bundle)
+	assert.ErrorContains(t, err, "notebook ./doesnt_exist.py not found")
+}
+
+func TestPipelineNotebookDoesNotExistError(t *testing.T) {
+	dir := t.TempDir()
+
+	bundle := &bundle.Bundle{
+		Config: config.Root{
+			Path: dir,
+			Resources: config.Resources{
+				Pipelines: map[string]*resources.Pipeline{
+					"pipeline": {
+						PipelineSpec: &pipelines.PipelineSpec{
+							Libraries: []pipelines.PipelineLibrary{
+								{
+									Notebook: &pipelines.NotebookLibrary{
+										Path: "./doesnt_exist.py",
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+
+	_, err := mutator.TranslateNotebookPaths().Apply(context.Background(), bundle)
+	assert.ErrorContains(t, err, "notebook ./doesnt_exist.py not found")
+}

libs/notebook/detect.go

@@ -39,6 +39,14 @@ func readHeader(path string) ([]byte, error) {
 func Detect(path string) (notebook bool, language workspace.Language, err error) {
 	header := ""
 
+	buf, err := readHeader(path)
+	if err != nil {
+		return false, "", err
+	}
+	scanner := bufio.NewScanner(bytes.NewReader(buf))
+	scanner.Scan()
+	fileHeader := scanner.Text()
+
 	// Determine which header to expect based on filename extension.
 	ext := strings.ToLower(filepath.Ext(path))
 	switch ext {
@@ -60,14 +68,7 @@ func Detect(path string) (notebook bool, language workspace.Language, err error)
 		return false, "", nil
 	}
 
-	buf, err := readHeader(path)
-	if err != nil {
-		return false, "", err
-	}
-
-	scanner := bufio.NewScanner(bytes.NewReader(buf))
-	scanner.Scan()
-	if scanner.Text() != header {
+	if fileHeader != header {
 		return false, "", nil
 	}
 

libs/notebook/detect_test.go

@@ -49,13 +49,19 @@ func TestDetectCallsDetectJupyter(t *testing.T) {
 }
 
 func TestDetectUnknownExtension(t *testing.T) {
-	nb, _, err := Detect("./testdata/doesntexist.foobar")
+	_, _, err := Detect("./testdata/doesntexist.foobar")
+	assert.True(t, os.IsNotExist(err))
+
+	nb, _, err := Detect("./testdata/unknown_extension.foobar")
 	require.NoError(t, err)
 	assert.False(t, nb)
 }
 
 func TestDetectNoExtension(t *testing.T) {
-	nb, _, err := Detect("./testdata/doesntexist")
+	_, _, err := Detect("./testdata/doesntexist")
+	assert.True(t, os.IsNotExist(err))
+
+	nb, _, err := Detect("./testdata/no_extension")
 	require.NoError(t, err)
 	assert.False(t, nb)
 }

libs/notebook/testdata/no_extension

@@ -0,0 +1 @@
+# Databricks notebook source

libs/notebook/testdata/unknown_extension.foobar

@@ -0,0 +1 @@
+# Databricks notebook source