Add default value for `volume_type` for DABs (#1952)

## Changes

The Unity Catalog volumes API requires a `volume_type` argument when
creating volumes. In the context of DABs, it's unnecessary to require
users to specify the volume type every time. We can default to "MANAGED"
instead.

This PR is similar to https://github.com/databricks/cli/pull/1743 which
does the same for dashboards.

## Tests
Unit test

bundle/config/mutator/configure_volume_defaults.go

@@ -0,0 +1,44 @@
+package mutator
+
+import (
+	"context"
+
+	"github.com/databricks/cli/bundle"
+	"github.com/databricks/cli/libs/diag"
+	"github.com/databricks/cli/libs/dyn"
+)
+
+type configureVolumeDefaults struct{}
+
+func ConfigureVolumeDefaults() bundle.Mutator {
+	return &configureVolumeDefaults{}
+}
+
+func (m *configureVolumeDefaults) Name() string {
+	return "ConfigureVolumeDefaults"
+}
+
+func (m *configureVolumeDefaults) Apply(ctx context.Context, b *bundle.Bundle) diag.Diagnostics {
+	var diags diag.Diagnostics
+
+	pattern := dyn.NewPattern(
+		dyn.Key("resources"),
+		dyn.Key("volumes"),
+		dyn.AnyKey(),
+	)
+
+	// Configure defaults for all volumes.
+	err := b.Config.Mutate(func(v dyn.Value) (dyn.Value, error) {
+		return dyn.MapByPattern(v, pattern, func(p dyn.Path, v dyn.Value) (dyn.Value, error) {
+			var err error
+			v, err = setIfNotExists(v, dyn.NewPath(dyn.Key("volume_type")), dyn.V("MANAGED"))
+			if err != nil {
+				return dyn.InvalidValue, err
+			}
+			return v, nil
+		})
+	})
+
+	diags = diags.Extend(diag.FromErr(err))
+	return diags
+}

bundle/config/mutator/configure_volume_defaults_test.go

@@ -0,0 +1,75 @@
+package mutator_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/databricks/cli/bundle"
+	"github.com/databricks/cli/bundle/config"
+	"github.com/databricks/cli/bundle/config/mutator"
+	"github.com/databricks/cli/bundle/config/resources"
+	"github.com/databricks/cli/bundle/internal/bundletest"
+	"github.com/databricks/cli/libs/dyn"
+	"github.com/databricks/databricks-sdk-go/service/catalog"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestConfigureVolumeDefaultsVolumeType(t *testing.T) {
+	b := &bundle.Bundle{
+		Config: config.Root{
+			Resources: config.Resources{
+				Volumes: map[string]*resources.Volume{
+					"v1": {
+						// Empty string is skipped.
+						// See below for how it is set.
+						CreateVolumeRequestContent: &catalog.CreateVolumeRequestContent{
+							VolumeType: "",
+						},
+					},
+					"v2": {
+						// Non-empty string is skipped.
+						CreateVolumeRequestContent: &catalog.CreateVolumeRequestContent{
+							VolumeType: "already-set",
+						},
+					},
+					"v3": {
+						// No volume type set.
+					},
+					"v4": nil,
+				},
+			},
+		},
+	}
+
+	// We can't set an empty string in the typed configuration.
+	// Do it on the dyn.Value directly.
+	bundletest.Mutate(t, b, func(v dyn.Value) (dyn.Value, error) {
+		return dyn.Set(v, "resources.volumes.v1.volume_type", dyn.V(""))
+	})
+
+	diags := bundle.Apply(context.Background(), b, mutator.ConfigureVolumeDefaults())
+	require.NoError(t, diags.Error())
+
+	var v dyn.Value
+	var err error
+
+	// Set to empty string; unchanged.
+	v, err = dyn.Get(b.Config.Value(), "resources.volumes.v1.volume_type")
+	require.NoError(t, err)
+	assert.Equal(t, "", v.MustString())
+
+	// Set to non-empty string; unchanged.
+	v, err = dyn.Get(b.Config.Value(), "resources.volumes.v2.volume_type")
+	require.NoError(t, err)
+	assert.Equal(t, "already-set", v.MustString())
+
+	// Not set; set to default.
+	v, err = dyn.Get(b.Config.Value(), "resources.volumes.v3.volume_type")
+	require.NoError(t, err)
+	assert.Equal(t, "MANAGED", v.MustString())
+
+	// No valid volume; No change.
+	_, err = dyn.Get(b.Config.Value(), "resources.volumes.v4.volume_type")
+	assert.True(t, dyn.IsCannotTraverseNilError(err))
+}

bundle/internal/schema/main.go

@@ -93,6 +93,24 @@ func removeJobsFields(typ reflect.Type, s jsonschema.Schema) jsonschema.Schema {
 	return s
 }
 
+// While volume_type is required in the volume create API, DABs automatically sets
+// it's value to "MANAGED" if it's not provided. Thus, we make it optional
+// in the bundle schema.
+func makeVolumeTypeOptional(typ reflect.Type, s jsonschema.Schema) jsonschema.Schema {
+	if typ != reflect.TypeOf(resources.Volume{}) {
+		return s
+	}
+
+	res := []string{}
+	for _, r := range s.Required {
+		if r != "volume_type" {
+			res = append(res, r)
+		}
+	}
+	s.Required = res
+	return s
+}
+
 func main() {
 	if len(os.Args) != 2 {
 		fmt.Println("Usage: go run main.go <output-file>")
@@ -118,6 +136,7 @@ func main() {
 		p.addDescriptions,
 		p.addEnums,
 		removeJobsFields,
+		makeVolumeTypeOptional,
 		addInterpolationPatterns,
 	})
 	if err != nil {

bundle/internal/schema/testdata/fail/incorrect_volume_type.yml

@@ -0,0 +1,10 @@
+bundle:
+  name: volume with incorrect type
+
+resources:
+  volumes:
+    foo:
+      catalog_name: main
+      name: my_volume
+      schema_name: myschema
+      volume_type: incorrect_type

bundle/internal/schema/testdata/pass/volume.yml

@@ -0,0 +1,9 @@
+bundle:
+  name: a volume
+
+resources:
+  volumes:
+    foo:
+      catalog_name: main
+      name: my_volume
+      schema_name: myschema

bundle/phases/initialize.go

@@ -68,6 +68,7 @@ func Initialize() bundle.Mutator {
 			mutator.SetRunAs(),
 			mutator.OverrideCompute(),
 			mutator.ConfigureDashboardDefaults(),
+			mutator.ConfigureVolumeDefaults(),
 			mutator.ProcessTargetMode(),
 			mutator.ApplyPresets(),
 			mutator.DefaultQueueing(),

bundle/schema/jsonschema.json

@@ -791,6 +791,51 @@
                   }
                 ]
               },
+              "resources.Volume": {
+                "anyOf": [
+                  {
+                    "type": "object",
+                    "properties": {
+                      "catalog_name": {
+                        "description": "The name of the catalog where the schema and the volume are",
+                        "$ref": "#/$defs/string"
+                      },
+                      "comment": {
+                        "description": "The comment attached to the volume",
+                        "$ref": "#/$defs/string"
+                      },
+                      "grants": {
+                        "$ref": "#/$defs/slice/github.com/databricks/cli/bundle/config/resources.Grant"
+                      },
+                      "name": {
+                        "description": "The name of the volume",
+                        "$ref": "#/$defs/string"
+                      },
+                      "schema_name": {
+                        "description": "The name of the schema where the volume is",
+                        "$ref": "#/$defs/string"
+                      },
+                      "storage_location": {
+                        "description": "The storage location on the cloud",
+                        "$ref": "#/$defs/string"
+                      },
+                      "volume_type": {
+                        "$ref": "#/$defs/github.com/databricks/databricks-sdk-go/service/catalog.VolumeType"
+                      }
+                    },
+                    "additionalProperties": false,
+                    "required": [
+                      "catalog_name",
+                      "name",
+                      "schema_name"
+                    ]
+                  },
+                  {
+                    "type": "string",
+                    "pattern": "\\$\\{(var(\\.[a-zA-Z]+([-_]?[a-zA-Z0-9]+)*(\\[[0-9]+\\])*)+)\\}"
+                  }
+                ]
+              },
               "variable.Lookup": {
                 "anyOf": [
                   {
@@ -963,6 +1008,9 @@
                     },
                     "name": {
                       "$ref": "#/$defs/string"
+                    },
+                    "uuid": {
+                      "$ref": "#/$defs/string"
                     }
                   },
                   "additionalProperties": false,
@@ -1157,6 +1205,9 @@
                     },
                     "schemas": {
                       "$ref": "#/$defs/map/github.com/databricks/cli/bundle/config/resources.Schema"
+                    },
+                    "volumes": {
+                      "$ref": "#/$defs/map/github.com/databricks/cli/bundle/config/resources.Volume"
                     }
                   },
                   "additionalProperties": false
@@ -1558,6 +1609,13 @@
                 }
               ]
             },
+            "catalog.VolumeType": {
+              "type": "string",
+              "enum": [
+                "EXTERNAL",
+                "MANAGED"
+              ]
+            },
             "compute.Adlsgen2Info": {
               "anyOf": [
                 {
@@ -5565,6 +5623,20 @@
                     }
                   ]
                 },
+                "resources.Volume": {
+                  "anyOf": [
+                    {
+                      "type": "object",
+                      "additionalProperties": {
+                        "$ref": "#/$defs/github.com/databricks/cli/bundle/config/resources.Volume"
+                      }
+                    },
+                    {
+                      "type": "string",
+                      "pattern": "\\$\\{(var(\\.[a-zA-Z]+([-_]?[a-zA-Z0-9]+)*(\\[[0-9]+\\])*)+)\\}"
+                    }
+                  ]
+                },
                 "variable.TargetVariable": {
                   "anyOf": [
                     {