Disable debug metrics for components inside foreach, and for foreach …

…itself.

internal/runtime/alloy.go

@@ -207,17 +207,22 @@ func newController(o controllerOptions) *Runtime {
 			OnExportsChange: o.OnExportsChange,
 			Registerer:      o.Reg,
 			ControllerID:    o.ControllerID,
-			NewModuleController: func(id string) controller.ModuleController {
+			NewModuleController: func(opts controller.ModuleControllerOpts) controller.ModuleController {
+				reg := o.Reg
+				if opts.Reg != nil {
+					reg = opts.Reg
+				}
+
 				return newModuleController(&moduleControllerOptions{
 					ComponentRegistry:    o.ComponentRegistry,
 					ModuleRegistry:       o.ModuleRegistry,
 					Logger:               log,
 					Tracer:               tracer,
-					Reg:                  o.Reg,
+					Reg:                  reg,
 					DataPath:             o.DataPath,
 					MinStability:         o.MinStability,
 					EnableCommunityComps: o.EnableCommunityComps,
-					ID:                   id,
+					ID:                   opts.Id,
 					ServiceMap:           serviceMap,
 					WorkerPool:           workerPool,
 				})

internal/runtime/foreach_test.go

@@ -4,13 +4,17 @@ import (
 	"context"
 	"os"
 	"path/filepath"
+	"strconv"
+	"strings"
 	"sync"
 	"testing"
 	"time"
 
 	"github.com/grafana/alloy/internal/component"
 	"github.com/grafana/alloy/internal/runtime"
 	alloy_runtime "github.com/grafana/alloy/internal/runtime"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/testutil"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/tools/txtar"
 )
@@ -27,20 +31,42 @@ func TestForeach(t *testing.T) {
 			if tc.update != nil {
 				testConfigForEach(t, tc.main, tc.reloadConfig, func() {
 					require.NoError(t, os.WriteFile(tc.update.name, []byte(tc.update.updateConfig), 0664))
-				})
+				}, nil, nil)
 			} else {
-				testConfigForEach(t, tc.main, tc.reloadConfig, nil)
+				testConfigForEach(t, tc.main, tc.reloadConfig, nil, nil, nil)
+			}
+		})
+	}
+}
+
+func TestForeachMetrics(t *testing.T) {
+	directory := "./testdata/foreach_metrics"
+	for _, file := range getTestFiles(directory, t) {
+		tc := buildTestForEach(t, filepath.Join(directory, file.Name()))
+		t.Run(tc.description, func(t *testing.T) {
+			if tc.module != "" {
+				defer os.Remove("module.alloy")
+				require.NoError(t, os.WriteFile("module.alloy", []byte(tc.module), 0664))
+			}
+			if tc.update != nil {
+				testConfigForEach(t, tc.main, tc.reloadConfig, func() {
+					require.NoError(t, os.WriteFile(tc.update.name, []byte(tc.update.updateConfig), 0664))
+				}, tc.expectedMetrics, tc.expectedDurationMetrics)
+			} else {
+				testConfigForEach(t, tc.main, tc.reloadConfig, nil, tc.expectedMetrics, tc.expectedDurationMetrics)
 			}
 		})
 	}
 }
 
 type testForEachFile struct {
-	description  string      // description at the top of the txtar file
-	main         string      // root config that the controller should load
-	module       string      // module imported by the root config
-	reloadConfig string      // root config that the controller should apply on reload
-	update       *updateFile // update can be used to update the content of a file at runtime
+	description             string      // description at the top of the txtar file
+	main                    string      // root config that the controller should load
+	module                  string      // module imported by the root config
+	reloadConfig            string      // root config that the controller should apply on reload
+	update                  *updateFile // update can be used to update the content of a file at runtime
+	expectedMetrics         *string     // expected prometheus metrics
+	expectedDurationMetrics *int        // expected prometheus duration metrics - check those separately as they vary with each test run
 }
 
 func buildTestForEach(t *testing.T, filename string) testForEachFile {
@@ -62,14 +88,22 @@ func buildTestForEach(t *testing.T, filename string) testForEachFile {
 			}
 		case "reload_config.alloy":
 			tc.reloadConfig = string(alloyConfig.Data)
+		case "expected_metrics.prom":
+			expectedMetrics := string(alloyConfig.Data)
+			tc.expectedMetrics = &expectedMetrics
+		case "expected_duration_metrics.prom":
+			expectedDurationMetrics, err := strconv.Atoi(strings.TrimSpace(string((alloyConfig.Data))))
+			require.NoError(t, err)
+			tc.expectedDurationMetrics = &expectedDurationMetrics
 		}
 	}
 	return tc
 }
 
-func testConfigForEach(t *testing.T, config string, reloadConfig string, update func()) {
+func testConfigForEach(t *testing.T, config string, reloadConfig string, update func(), expectedMetrics *string, expectedDurationMetrics *int) {
 	defer verifyNoGoroutineLeaks(t)
-	ctrl, f := setup(t, config)
+	reg := prometheus.NewRegistry()
+	ctrl, f := setup(t, config, reg)
 
 	err := ctrl.LoadSource(f, nil, "")
 	require.NoError(t, err)
@@ -92,6 +126,34 @@ func testConfigForEach(t *testing.T, config string, reloadConfig string, update
 		return sum >= 10
 	}, 3*time.Second, 10*time.Millisecond)
 
+	if expectedDurationMetrics != nil {
+		// These metrics have different values in each run.
+		// Hence, we can't compare their values from run to run.
+		// But we can check if the metric exists as a whole, which is good enough.
+		metricsToCheck := []string{
+			"alloy_component_dependencies_wait_seconds",
+			"alloy_component_evaluation_seconds",
+		}
+
+		countedMetrics, err := testutil.GatherAndCount(reg, metricsToCheck...)
+		require.NoError(t, err)
+		require.Equal(t, *expectedDurationMetrics, countedMetrics)
+	}
+
+	if expectedMetrics != nil {
+		// These metrics have fixed values.
+		// Hence, we can compare their values from run to run.
+		metricsToCheck := []string{
+			"alloy_component_controller_evaluating",
+			"alloy_component_controller_running_components",
+			"alloy_component_evaluation_queue_size",
+			"pulse_count",
+		}
+
+		err := testutil.GatherAndCompare(reg, strings.NewReader(*expectedMetrics), metricsToCheck...)
+		require.NoError(t, err)
+	}
+
 	if update != nil {
 		update()
 

internal/runtime/import_git_test.go

@@ -55,7 +55,7 @@ testImport.add "cc" {
 	runGit(t, testRepo, "commit", "-m \"test\"")
 
 	defer verifyNoGoroutineLeaks(t)
-	ctrl, f := setup(t, main)
+	ctrl, f := setup(t, main, nil)
 	err = ctrl.LoadSource(f, nil, "")
 	require.NoError(t, err)
 	ctx, cancel := context.WithCancel(context.Background())
@@ -122,7 +122,7 @@ testImport.add "cc" {
 	runGit(t, testRepo, "commit", "-m \"test\"")
 
 	defer verifyNoGoroutineLeaks(t)
-	ctrl, f := setup(t, main)
+	ctrl, f := setup(t, main, nil)
 	err = ctrl.LoadSource(f, nil, "")
 	require.NoError(t, err)
 	ctx, cancel := context.WithCancel(context.Background())
@@ -205,7 +205,7 @@ testImport.add "cc" {
 	runGit(t, testRepo, "commit", "-m \"test2\"")
 
 	defer verifyNoGoroutineLeaks(t)
-	ctrl, f := setup(t, main)
+	ctrl, f := setup(t, main, nil)
 	err = ctrl.LoadSource(f, nil, "")
 	require.NoError(t, err)
 	ctx, cancel := context.WithCancel(context.Background())
@@ -269,7 +269,7 @@ testImport.add "cc" {
 
 	defer verifyNoGoroutineLeaks(t)
 
-	ctrl, f := setup(t, main)
+	ctrl, f := setup(t, main, nil)
 	err = ctrl.LoadSource(f, nil, "")
 	require.NoError(t, err)
 	ctx, cancel := context.WithCancel(context.Background())
@@ -354,7 +354,7 @@ testImport.add "cc" {
 	runGit(t, testRepo, "commit", "-m \"test\"")
 
 	defer verifyNoGoroutineLeaks(t)
-	ctrl, f := setup(t, main)
+	ctrl, f := setup(t, main, nil)
 	err = ctrl.LoadSource(f, nil, "")
 	expectedErr := vcs.InvalidRevisionError{
 		Revision: "nonexistent",

internal/runtime/import_test.go

@@ -16,6 +16,7 @@ import (
 	"github.com/grafana/alloy/internal/runtime/logging"
 	"github.com/grafana/alloy/internal/service"
 	"github.com/grafana/alloy/internal/util"
+	"github.com/prometheus/client_golang/prometheus"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/tools/txtar"
 
@@ -298,7 +299,7 @@ func TestImportError(t *testing.T) {
 
 func testConfig(t *testing.T, config string, reloadConfig string, update func()) {
 	defer verifyNoGoroutineLeaks(t)
-	ctrl, f := setup(t, config)
+	ctrl, f := setup(t, config, nil)
 
 	err := ctrl.LoadSource(f, nil, "")
 	require.NoError(t, err)
@@ -351,7 +352,7 @@ func testConfig(t *testing.T, config string, reloadConfig string, update func())
 
 func testConfigError(t *testing.T, config string, expectedError string) {
 	defer verifyNoGoroutineLeaks(t)
-	ctrl, f := setup(t, config)
+	ctrl, f := setup(t, config, nil)
 	err := ctrl.LoadSource(f, nil, "")
 	require.ErrorContains(t, err, expectedError)
 	ctx, cancel := context.WithCancel(context.Background())
@@ -368,14 +369,14 @@ func testConfigError(t *testing.T, config string, expectedError string) {
 	}()
 }
 
-func setup(t *testing.T, config string) (*alloy_runtime.Runtime, *alloy_runtime.Source) {
+func setup(t *testing.T, config string, reg prometheus.Registerer) (*alloy_runtime.Runtime, *alloy_runtime.Source) {
 	s, err := logging.New(os.Stderr, logging.DefaultOptions)
 	require.NoError(t, err)
 	ctrl := alloy_runtime.New(alloy_runtime.Options{
 		Logger:       s,
 		DataPath:     t.TempDir(),
 		MinStability: featuregate.StabilityPublicPreview,
-		Reg:          nil,
+		Reg:          reg,
 		Services:     []service.Service{},
 	})
 	f, err := alloy_runtime.ParseSource(t.Name(), []byte(config))

internal/runtime/internal/controller/loader_test.go

@@ -83,7 +83,7 @@ func TestLoader(t *testing.T) {
 				MinStability:      stability,
 				OnBlockNodeUpdate: func(cn controller.BlockNode) { /* no-op */ },
 				Registerer:        prometheus.NewRegistry(),
-				NewModuleController: func(id string) controller.ModuleController {
+				NewModuleController: func(opts controller.ModuleControllerOpts) controller.ModuleController {
 					return nil
 				},
 			},
@@ -382,7 +382,7 @@ func TestLoader_Services(t *testing.T) {
 				MinStability:      stability,
 				OnBlockNodeUpdate: func(cn controller.BlockNode) { /* no-op */ },
 				Registerer:        prometheus.NewRegistry(),
-				NewModuleController: func(id string) controller.ModuleController {
+				NewModuleController: func(opts controller.ModuleControllerOpts) controller.ModuleController {
 					return nil
 				},
 			},
@@ -439,7 +439,7 @@ func TestScopeWithFailingComponent(t *testing.T) {
 				MinStability:      featuregate.StabilityPublicPreview,
 				OnBlockNodeUpdate: func(cn controller.BlockNode) { /* no-op */ },
 				Registerer:        prometheus.NewRegistry(),
-				NewModuleController: func(id string) controller.ModuleController {
+				NewModuleController: func(opts controller.ModuleControllerOpts) controller.ModuleController {
 					return fakeModuleController{}
 				},
 			},

internal/runtime/internal/controller/node_builtin_component.go

@@ -60,20 +60,25 @@ func (id ComponentID) Equals(other ComponentID) bool {
 // DialFunc is a function to establish a network connection.
 type DialFunc func(ctx context.Context, network, address string) (net.Conn, error)
 
+type ModuleControllerOpts struct {
+	Id  string
+	Reg prometheus.Registerer
+}
+
 // ComponentGlobals are used by BuiltinComponentNodes to build managed components. All
 // BuiltinComponentNodes should use the same ComponentGlobals.
 type ComponentGlobals struct {
-	Logger               *logging.Logger                        // Logger shared between all managed components.
-	TraceProvider        trace.TracerProvider                   // Tracer shared between all managed components.
-	DataPath             string                                 // Shared directory where component data may be stored
-	MinStability         featuregate.Stability                  // Minimum allowed stability level for features
-	OnBlockNodeUpdate    func(cn BlockNode)                     // Informs controller that we need to reevaluate
-	OnExportsChange      func(exports map[string]any)           // Invoked when the managed component updated its exports
-	Registerer           prometheus.Registerer                  // Registerer for serving Alloy and component metrics
-	ControllerID         string                                 // ID of controller.
-	NewModuleController  func(id string) ModuleController       // Func to generate a module controller.
-	GetServiceData       func(name string) (interface{}, error) // Get data for a service.
-	EnableCommunityComps bool                                   // Enables the use of community components.
+	Logger               *logging.Logger                                  // Logger shared between all managed components.
+	TraceProvider        trace.TracerProvider                             // Tracer shared between all managed components.
+	DataPath             string                                           // Shared directory where component data may be stored
+	MinStability         featuregate.Stability                            // Minimum allowed stability level for features
+	OnBlockNodeUpdate    func(cn BlockNode)                               // Informs controller that we need to reevaluate
+	OnExportsChange      func(exports map[string]any)                     // Invoked when the managed component updated its exports
+	Registerer           prometheus.Registerer                            // Registerer for serving Alloy and component metrics
+	ControllerID         string                                           // ID of controller.
+	NewModuleController  func(opts ModuleControllerOpts) ModuleController // Func to generate a module controller.
+	GetServiceData       func(name string) (interface{}, error)           // Get data for a service.
+	EnableCommunityComps bool                                             // Enables the use of community components.
 }
 
 // BuiltinComponentNode is a controller node which manages a builtin component.
@@ -146,7 +151,7 @@ func NewBuiltinComponentNode(globals ComponentGlobals, reg component.Registratio
 		componentName:     strings.Join(b.Name, "."),
 		reg:               reg,
 		exportsType:       getExportsType(reg),
-		moduleController:  globals.NewModuleController(globalID),
+		moduleController:  globals.NewModuleController(ModuleControllerOpts{Id: globalID}),
 		OnBlockNodeUpdate: globals.OnBlockNodeUpdate,
 
 		block: b,

internal/runtime/internal/controller/node_builtin_component_test.go

@@ -13,7 +13,7 @@ func TestGlobalID(t *testing.T) {
 		DataPath:     "/data/",
 		MinStability: featuregate.StabilityPublicPreview,
 		ControllerID: "module.file",
-		NewModuleController: func(id string) ModuleController {
+		NewModuleController: func(opts ModuleControllerOpts) ModuleController {
 			return nil
 		},
 	}, &BuiltinComponentNode{
@@ -28,7 +28,7 @@ func TestLocalID(t *testing.T) {
 		DataPath:     "/data/",
 		MinStability: featuregate.StabilityPublicPreview,
 		ControllerID: "",
-		NewModuleController: func(id string) ModuleController {
+		NewModuleController: func(opts ModuleControllerOpts) ModuleController {
 			return nil
 		},
 	}, &BuiltinComponentNode{