[Python] Add telemetry (#2713)

## Changes
Add telemetry for PythonMutator. It includes:
- counts of added and updated resources
- counts of declared mutators and resource loaders

## Why
It allows to track adoption patterns of `experimental/python` feature.

## Tests
Unit test

Author: kanterov

bundle/bundle.go

@@ -36,10 +36,12 @@ const internalFolder = ".internal"
 // This struct is used as a communication channel to collect metrics
 // from all over the bundle codebase to finally be emitted as telemetry.
 type Metrics struct {
-	ConfigurationFileCount int64
-	TargetCount            int64
-	DeploymentId           uuid.UUID
-	BoolValues             []protos.BoolMapEntry
+	ConfigurationFileCount      int64
+	TargetCount                 int64
+	DeploymentId                uuid.UUID
+	BoolValues                  []protos.BoolMapEntry
+	PythonAddedResourcesCount   int64
+	PythonUpdatedResourcesCount int64
 }
 
 func (m *Metrics) AddBoolValue(key string, value bool) {

bundle/config/mutator/python/python_mutator.go

@@ -258,6 +258,13 @@ func (m *pythonMutator) Apply(ctx context.Context, b *bundle.Bundle) diag.Diagno
 		return newRoot, nil
 	})
 
+	// don't instrument deprecated phases
+	if m.phase == PythonMutatorPhaseLoadResources || m.phase == PythonMutatorPhaseApplyMutators {
+		// we can precisely track resources that are added/updated, so sum doesn't double-count
+		b.Metrics.PythonUpdatedResourcesCount += int64(result.UpdatedResources.Size())
+		b.Metrics.PythonAddedResourcesCount += int64(result.AddedResources.Size())
+	}
+
 	if err == mutateDiagsHasError {
 		if !mutateDiags.HasError() {
 			panic("mutateDiags has no error, but error is expected")

bundle/config/mutator/python/python_mutator_test.go

@@ -166,6 +166,9 @@ workspace: { current_user: { userName: test }}`)
 	})
 	assert.NoError(t, err)
 
+	assert.Equal(t, int64(2), b.Metrics.PythonAddedResourcesCount)
+	assert.Equal(t, int64(0), b.Metrics.PythonUpdatedResourcesCount)
+
 	assert.Equal(t, 1, len(diags))
 	assert.Equal(t, "job doesn't have any tasks", diags[0].Summary)
 	assert.Equal(t, []dyn.Location{
@@ -243,6 +246,9 @@ resources:
 		return v, nil
 	})
 	assert.NoError(t, err)
+
+	assert.Equal(t, int64(0), b.Metrics.PythonAddedResourcesCount)
+	assert.Equal(t, int64(1), b.Metrics.PythonUpdatedResourcesCount)
 }
 
 func TestPythonMutator_badOutput(t *testing.T) {

bundle/config/mutator/resourcemutator/resource_key.go

@@ -37,6 +37,16 @@ func (r ResourceKeySet) IsEmpty() bool {
 	return len(r) == 0
 }
 
+func (r ResourceKeySet) Size() int {
+	size := 0
+
+	for _, resources := range r {
+		size += len(resources)
+	}
+
+	return size
+}
+
 // AddPattern adds all resource keys that match the pattern.
 func (r ResourceKeySet) AddPattern(pattern dyn.Pattern, root dyn.Value) error {
 	if len(pattern) != 3 {

bundle/config/mutator/resourcemutator/resource_key_test.go

@@ -127,4 +127,5 @@ func TestResourceKeySet_AddResourceKey(t *testing.T) {
 		},
 		set.ToArray(),
 	)
+	assert.Equal(t, 2, set.Size())
 }

bundle/phases/deploy.go

@@ -333,6 +333,11 @@ func logTelemetry(ctx context.Context, b *bundle.Bundle) {
 		mode = protos.BundleModeProduction
 	}
 
+	experimentalConfig := b.Config.Experimental
+	if experimentalConfig == nil {
+		experimentalConfig = &config.Experimental{}
+	}
+
 	telemetry.Log(ctx, protos.DatabricksCliLog{
 		BundleDeployEvent: &protos.BundleDeployEvent{
 			BundleUuid:   bundleUuid,
@@ -358,11 +363,15 @@ func logTelemetry(ctx context.Context, b *bundle.Bundle) {
 			ResourceDashboardIDs: dashboardIds,
 
 			Experimental: &protos.BundleDeployExperimental{
-				BundleMode:                mode,
-				ConfigurationFileCount:    b.Metrics.ConfigurationFileCount,
-				TargetCount:               b.Metrics.TargetCount,
-				WorkspaceArtifactPathType: artifactPathType,
-				BoolValues:                b.Metrics.BoolValues,
+				BundleMode:                  mode,
+				ConfigurationFileCount:      b.Metrics.ConfigurationFileCount,
+				TargetCount:                 b.Metrics.TargetCount,
+				WorkspaceArtifactPathType:   artifactPathType,
+				BoolValues:                  b.Metrics.BoolValues,
+				PythonAddedResourcesCount:   b.Metrics.PythonAddedResourcesCount,
+				PythonUpdatedResourcesCount: b.Metrics.PythonUpdatedResourcesCount,
+				PythonResourceLoadersCount:  int64(len(experimentalConfig.Python.Resources)),
+				PythonResourceMutatorsCount: int64(len(experimentalConfig.Python.Mutators)),
 			},
 		},
 	})

libs/telemetry/protos/bundle_deploy.go

@@ -68,6 +68,18 @@ type BundleDeployExperimental struct {
 
 	// Execution time per mutator for a selected subset of mutators.
 	BundleMutatorExecutionTimeMs []IntMapEntry `json:"bundle_mutator_execution_time_ms,omitempty"`
+
+	// Number of resources added by PythonMutator
+	PythonAddedResourcesCount int64 `json:"python_added_resources_count,omitempty"`
+
+	// Number of resources updated by PythonMutator
+	PythonUpdatedResourcesCount int64 `json:"python_updated_resources_count,omitempty"`
+
+	// Number of resource loaders declared at 'python/resources' in databricks.yml
+	PythonResourceLoadersCount int64 `json:"python_resource_loaders_count,omitempty"`
+
+	// Number of resource mutators declared at 'python/mutators' in databricks.yml
+	PythonResourceMutatorsCount int64 `json:"python_resource_mutators_count,omitempty"`
 }
 
 type BoolMapEntry struct {