Merge branch 'main' into fix/error-response-handler-null-4284-4286

* feat: add support for configurable pre expanded levels

When a span is expanded, now it will return nested children
up to a max depth level

* feat: show spinner on expanding span and fix autoscroll

Two improvemnts are included in this commit:
- Show a loading spiner in UI when a span is expanded
  to signal api call.
- Don't auto scroll the waterfall to bring the selected
  span to centre in case it's expanded or scrolled up
  because it looks very flickering behaviour to user

* feat: add support for returning all the spans

If total spans are less than a max value.
This allows UI to not have to call API
for smaller spans on ever collapse/uncollapse

* Revert "feat: show spinner on expanding span and fix autoscroll"

This reverts commit 6bd194dfb4.

* chore: add tests

* chore: make the code changes more easy to understand

* chore: cleanup traversal in trace waterfall

* chore: rename variables to be self descriptive

* chore: add rests for auto expand

* chore: add tests for getAllSpans

---------

Co-authored-by: nityanandagohain <nityanandagohain@gmail.com>

frontend/src/api/ErrorResponseHandlerV2.test.ts

@@ -0,0 +1,143 @@
+import { AxiosError } from 'axios';
+import { ErrorV2Resp } from 'types/api';
+import APIError from 'types/api/error';
+
+import { ErrorResponseHandlerV2 } from './ErrorResponseHandlerV2';
+
+function makeAxiosError(
+	overrides: Partial<AxiosError<ErrorV2Resp>>,
+): AxiosError<ErrorV2Resp> {
+	return {
+		isAxiosError: true,
+		name: 'AxiosError',
+		message: 'Request failed',
+		config: {} as any,
+		toJSON: () => ({}),
+		...overrides,
+	} as AxiosError<ErrorV2Resp>;
+}
+
+describe('ErrorResponseHandlerV2', () => {
+	describe('when the server responds with a well-formed error body', () => {
+		it('throws an APIError with fields from response.data.error', () => {
+			const error = makeAxiosError({
+				response: {
+					status: 403,
+					data: {
+						error: {
+							code: 'FORBIDDEN',
+							message: 'only editors/admins can access this resource',
+							url: '/api/v1/dashboards/123',
+							errors: [],
+						},
+					},
+					headers: {} as any,
+					config: {} as any,
+					statusText: 'Forbidden',
+				},
+			});
+
+			expect(() => ErrorResponseHandlerV2(error)).toThrow(APIError);
+			try {
+				ErrorResponseHandlerV2(error);
+			} catch (e) {
+				expect(e).toBeInstanceOf(APIError);
+				const apiError = e as APIError;
+				expect(apiError.getHttpStatusCode()).toBe(403);
+				expect(apiError.getErrorMessage()).toBe(
+					'only editors/admins can access this resource',
+				);
+				expect(apiError.getErrorCode()).toBe('FORBIDDEN');
+			}
+		});
+	});
+
+	describe('when the server responds with a null error body', () => {
+		it('throws an APIError without crashing, using fallback values', () => {
+			const error = makeAxiosError({
+				name: 'AxiosError',
+				message: 'timeout exceeded',
+				response: {
+					status: 504,
+					data: (null as unknown) as ErrorV2Resp,
+					headers: {} as any,
+					config: {} as any,
+					statusText: 'Gateway Timeout',
+				},
+			});
+
+			expect(() => ErrorResponseHandlerV2(error)).toThrow(APIError);
+			try {
+				ErrorResponseHandlerV2(error);
+			} catch (e) {
+				expect(e).toBeInstanceOf(APIError);
+				const apiError = e as APIError;
+				expect(apiError.getHttpStatusCode()).toBe(504);
+				expect(apiError.getErrorMessage()).toBe('timeout exceeded');
+			}
+		});
+
+		it('throws an APIError when response.data.error is missing', () => {
+			const error = makeAxiosError({
+				name: 'AxiosError',
+				message: 'Bad Gateway',
+				response: {
+					status: 502,
+					data: {} as ErrorV2Resp,
+					headers: {} as any,
+					config: {} as any,
+					statusText: 'Bad Gateway',
+				},
+			});
+
+			expect(() => ErrorResponseHandlerV2(error)).toThrow(APIError);
+			try {
+				ErrorResponseHandlerV2(error);
+			} catch (e) {
+				expect(e).toBeInstanceOf(APIError);
+				const apiError = e as APIError;
+				expect(apiError.getHttpStatusCode()).toBe(502);
+			}
+		});
+	});
+
+	describe('when no response is received (network/timeout)', () => {
+		it('throws an APIError using error.message', () => {
+			const error = makeAxiosError({
+				request: {},
+				name: 'ECONNABORTED',
+				message: 'timeout exceeded',
+				status: undefined,
+			});
+
+			expect(() => ErrorResponseHandlerV2(error)).toThrow(APIError);
+			try {
+				ErrorResponseHandlerV2(error);
+			} catch (e) {
+				expect(e).toBeInstanceOf(APIError);
+				const apiError = e as APIError;
+				expect(apiError.getErrorMessage()).toBe('timeout exceeded');
+			}
+		});
+	});
+
+	describe('when the error is a setup error (no request or response)', () => {
+		it('throws an APIError using error.name and error.message', () => {
+			const error = makeAxiosError({
+				name: 'Error',
+				message: 'Something went wrong setting up the request',
+			});
+
+			expect(() => ErrorResponseHandlerV2(error)).toThrow(APIError);
+			try {
+				ErrorResponseHandlerV2(error);
+			} catch (e) {
+				expect(e).toBeInstanceOf(APIError);
+				const apiError = e as APIError;
+				expect(apiError.getErrorMessage()).toBe(
+					'Something went wrong setting up the request',
+				);
+			}
+		});
+	});
+});

frontend/src/api/ErrorResponseHandlerV2.ts

@@ -8,13 +8,14 @@ export function ErrorResponseHandlerV2(error: AxiosError<ErrorV2Resp>): never {
 	// The request was made and the server responded with a status code
 	// that falls out of the range of 2xx
 	if (response) {
+		const errorData = response.data?.error;
 		throw new APIError({
 			httpStatusCode: response.status || 500,
 			error: {
-				code: response.data.error.code,
-				message: response.data.error.message,
-				url: response.data.error.url,
-				errors: response.data.error.errors,
+				code: errorData?.code ?? error.name,
+				message: errorData?.message ?? error.message,
+				url: errorData?.url ?? '',
+				errors: errorData?.errors ?? [],
 			},
 		});
 	}

frontend/src/components/InviteMembersModal/InviteMembersModal.tsx

@@ -202,19 +202,8 @@ function InviteMembersModal({
 			onComplete?.();
 		} catch (err) {
 			const apiErr = err as APIError;
-			if (apiErr?.getHttpStatusCode() === 409) {
-				toast.error(
-					touchedRows.length === 1
-						? `${touchedRows[0].email} is already a member`
-						: 'Invite for one or more users already exists',
-					{ richColors: true },
-				);
-			} else {
-				const errorMessage = apiErr?.getErrorMessage?.() ?? 'An error occurred';
-				toast.error(`Failed to send invites: ${errorMessage}`, {
-					richColors: true,
-				});
-			}
+			const errorMessage = apiErr?.getErrorMessage?.() ?? 'An error occurred';
+			toast.error(errorMessage, { richColors: true });
 		} finally {
 			setIsSubmitting(false);
 		}

frontend/src/components/InviteMembersModal/__tests__/InviteMembersModal.test.tsx

@@ -1,9 +1,18 @@
+import { toast } from '@signozhq/sonner';
 import inviteUsers from 'api/v1/invite/bulk/create';
 import sendInvite from 'api/v1/invite/create';
+import { StatusCodes } from 'http-status-codes';
 import { render, screen, userEvent, waitFor } from 'tests/test-utils';
+import APIError from 'types/api/error';
 
 import InviteMembersModal from '../InviteMembersModal';
 
+const makeApiError = (message: string, code = StatusCodes.CONFLICT): APIError =>
+	new APIError({
+		httpStatusCode: code,
+		error: { code: 'already_exists', message, url: '', errors: [] },
+	});
+
 jest.mock('api/v1/invite/create');
 jest.mock('api/v1/invite/bulk/create');
 jest.mock('@signozhq/sonner', () => ({
@@ -142,6 +151,90 @@ describe('InviteMembersModal', () => {
 		});
 	});
 
+	describe('error handling', () => {
+		it('shows BE message on single invite 409', async () => {
+			const user = userEvent.setup({ pointerEventsCheck: 0 });
+			mockSendInvite.mockRejectedValue(
+				makeApiError('An invite already exists for this email: single@signoz.io'),
+			);
+
+			render(<InviteMembersModal {...defaultProps} />);
+
+			await user.type(
+				screen.getAllByPlaceholderText('john@signoz.io')[0],
+				'single@signoz.io',
+			);
+			await user.click(screen.getAllByText('Select roles')[0]);
+			await user.click(await screen.findByText('Viewer'));
+			await user.click(
+				screen.getByRole('button', { name: /invite team members/i }),
+			);
+
+			await waitFor(() => {
+				expect(toast.error).toHaveBeenCalledWith(
+					'An invite already exists for this email: single@signoz.io',
+					expect.anything(),
+				);
+			});
+		});
+
+		it('shows BE message on bulk invite 409', async () => {
+			const user = userEvent.setup({ pointerEventsCheck: 0 });
+			mockInviteUsers.mockRejectedValue(
+				makeApiError('An invite already exists for this email: alice@signoz.io'),
+			);
+
+			render(<InviteMembersModal {...defaultProps} />);
+
+			const emailInputs = screen.getAllByPlaceholderText('john@signoz.io');
+			await user.type(emailInputs[0], 'alice@signoz.io');
+			await user.click(screen.getAllByText('Select roles')[0]);
+			await user.click(await screen.findByText('Viewer'));
+
+			await user.type(emailInputs[1], 'bob@signoz.io');
+			await user.click(screen.getAllByText('Select roles')[0]);
+			const editorOptions = await screen.findAllByText('Editor');
+			await user.click(editorOptions[editorOptions.length - 1]);
+
+			await user.click(
+				screen.getByRole('button', { name: /invite team members/i }),
+			);
+
+			await waitFor(() => {
+				expect(toast.error).toHaveBeenCalledWith(
+					'An invite already exists for this email: alice@signoz.io',
+					expect.anything(),
+				);
+			});
+		});
+
+		it('shows BE message on generic error', async () => {
+			const user = userEvent.setup({ pointerEventsCheck: 0 });
+			mockSendInvite.mockRejectedValue(
+				makeApiError('Internal server error', StatusCodes.INTERNAL_SERVER_ERROR),
+			);
+
+			render(<InviteMembersModal {...defaultProps} />);
+
+			await user.type(
+				screen.getAllByPlaceholderText('john@signoz.io')[0],
+				'single@signoz.io',
+			);
+			await user.click(screen.getAllByText('Select roles')[0]);
+			await user.click(await screen.findByText('Viewer'));
+			await user.click(
+				screen.getByRole('button', { name: /invite team members/i }),
+			);
+
+			await waitFor(() => {
+				expect(toast.error).toHaveBeenCalledWith(
+					'Internal server error',
+					expect.anything(),
+				);
+			});
+		});
+	});
+
 	it('uses inviteUsers (bulk) when multiple rows are filled', async () => {
 		const user = userEvent.setup({ pointerEventsCheck: 0 });
 		const onComplete = jest.fn();

frontend/src/container/AlertHistory/Statistics/AverageResolutionCard/AverageResolutionCard.tsx

@@ -16,9 +16,9 @@ function AverageResolutionCard({
 }: TotalTriggeredCardProps): JSX.Element {
 	return (
 		<StatsCard
-			displayValue={formatTime(currentAvgResolutionTime)}
-			totalCurrentCount={currentAvgResolutionTime}
-			totalPastCount={pastAvgResolutionTime}
+			displayValue={formatTime(+currentAvgResolutionTime)}
+			totalCurrentCount={+currentAvgResolutionTime}
+			totalPastCount={+pastAvgResolutionTime}
 			title="Avg. Resolution Time"
 			timeSeries={timeSeries}
 		/>

frontend/src/container/GeneralSettings/GeneralSettings.tsx

@@ -464,14 +464,10 @@ function GeneralSettings({
 		onModalToggleHandler(type);
 	};
 
-	const {
-		isCloudUser: isCloudUserVal,
-		isEnterpriseSelfHostedUser,
-	} = useGetTenantLicense();
+	const { isCloudUser: isCloudUserVal } = useGetTenantLicense();
 
 	const isAdmin = user.role === USER_ROLES.ADMIN;
-	const showCustomDomainSettings =
-		(isCloudUserVal || isEnterpriseSelfHostedUser) && isAdmin;
+	const showCustomDomainSettings = isCloudUserVal && isAdmin;
 
 	const renderConfig = [
 		{

frontend/src/container/GeneralSettings/__tests__/GeneralSettings.test.tsx

@@ -38,7 +38,6 @@ jest.mock('hooks/useComponentPermission', () => ({
 jest.mock('hooks/useGetTenantLicense', () => ({
 	useGetTenantLicense: jest.fn(() => ({
 		isCloudUser: false,
-		isEnterpriseSelfHostedUser: false,
 	})),
 }));
 
@@ -389,7 +388,6 @@ describe('GeneralSettings - S3 Logs Retention', () => {
 		beforeEach(() => {
 			(useGetTenantLicense as jest.Mock).mockReturnValue({
 				isCloudUser: true,
-				isEnterpriseSelfHostedUser: false,
 			});
 		});
 
@@ -411,15 +409,14 @@ describe('GeneralSettings - S3 Logs Retention', () => {
 		});
 	});
 
-	describe('Enterprise Self-Hosted User Rendering', () => {
+	describe('Non-cloud user rendering', () => {
 		beforeEach(() => {
 			(useGetTenantLicense as jest.Mock).mockReturnValue({
 				isCloudUser: false,
-				isEnterpriseSelfHostedUser: true,
 			});
 		});
 
-		it('should render CustomDomainSettings but not GeneralSettingsCloud', () => {
+		it('should not render CustomDomainSettings or GeneralSettingsCloud', () => {
 			render(
 				<GeneralSettings
 					metricsTtlValuesPayload={mockMetricsRetention}
@@ -432,12 +429,14 @@ describe('GeneralSettings - S3 Logs Retention', () => {
 				/>,
 			);
 
-			expect(screen.getByTestId('custom-domain-settings')).toBeInTheDocument();
+			expect(
+				screen.queryByTestId('custom-domain-settings'),
+			).not.toBeInTheDocument();
 			expect(
 				screen.queryByTestId('general-settings-cloud'),
 			).not.toBeInTheDocument();
 
-			// Save buttons should be visible for self-hosted
+			// Save buttons should be visible for non-cloud users (these are from retentions)
 			const saveButtons = screen.getAllByRole('button', { name: /save/i });
 			expect(saveButtons.length).toBeGreaterThan(0);
 		});

frontend/src/container/InfraMonitoringK8s/Volumes/K8sVolumesList.tsx

@@ -217,7 +217,7 @@ function K8sVolumesList({
 		{
 			dataSource: currentQuery.builder.queryData[0].dataSource,
 			aggregateAttribute: GetK8sEntityToAggregateAttribute(
-				K8sCategory.NODES,
+				K8sCategory.VOLUMES,
 				dotMetricsEnabled,
 			),
 			aggregateOperator: 'noop',
@@ -228,7 +228,7 @@ function K8sVolumesList({
 			queryKey: [currentQuery.builder.queryData[0].dataSource, 'noop'],
 		},
 		true,
-		K8sCategory.NODES,
+		K8sCategory.VOLUMES,
 	);
 
 	const query = useMemo(() => {
@@ -597,7 +597,7 @@ function K8sVolumesList({
 				isLoadingGroupByFilters={isLoadingGroupByFilters}
 				handleGroupByChange={handleGroupByChange}
 				selectedGroupBy={groupBy}
-				entity={K8sCategory.NODES}
+				entity={K8sCategory.VOLUMES}
 				showAutoRefresh={!selectedVolumeData}
 			/>
 			{isError && <Typography>{data?.error || 'Something went wrong'}</Typography>}

frontend/src/container/InfraMonitoringK8s/__tests__/Volumes/K8sVolumesList.test.tsx

@@ -0,0 +1,162 @@
+import setupCommonMocks from '../commonMocks';
+
+setupCommonMocks();
+
+import { QueryClient, QueryClientProvider } from 'react-query';
+// eslint-disable-next-line no-restricted-imports
+import { Provider } from 'react-redux';
+import { MemoryRouter } from 'react-router-dom';
+import { render, waitFor } from '@testing-library/react';
+import { FeatureKeys } from 'constants/features';
+import K8sVolumesList from 'container/InfraMonitoringK8s/Volumes/K8sVolumesList';
+import { rest, server } from 'mocks-server/server';
+import { IAppContext, IUser } from 'providers/App/types';
+import store from 'store';
+import { LicenseResModel } from 'types/api/licensesV3/getActive';
+
+const queryClient = new QueryClient({
+	defaultOptions: {
+		queries: {
+			retry: false,
+			cacheTime: 0,
+		},
+	},
+});
+
+const SERVER_URL = 'http://localhost/api';
+
+describe('K8sVolumesList - useGetAggregateKeys Category Regression', () => {
+	let requestsMade: Array<{
+		url: string;
+		params: URLSearchParams;
+		body?: any;
+	}> = [];
+
+	beforeEach(() => {
+		requestsMade = [];
+		queryClient.clear();
+
+		server.use(
+			rest.get(`${SERVER_URL}/v3/autocomplete/attribute_keys`, (req, res, ctx) => {
+				const url = req.url.toString();
+				const params = req.url.searchParams;
+
+				requestsMade.push({
+					url,
+					params,
+				});
+
+				return res(
+					ctx.status(200),
+					ctx.json({
+						status: 'success',
+						data: {
+							attributeKeys: [],
+						},
+					}),
+				);
+			}),
+			rest.post(`${SERVER_URL}/v1/pvcs/list`, (req, res, ctx) =>
+				res(
+					ctx.status(200),
+					ctx.json({
+						status: 'success',
+						data: {
+							type: 'list',
+							records: [],
+							groups: null,
+							total: 0,
+							sentAnyHostMetricsData: false,
+							isSendingK8SAgentMetrics: false,
+						},
+					}),
+				),
+			),
+		);
+	});
+
+	afterEach(() => {
+		server.resetHandlers();
+	});
+
+	it('should call aggregate keys API with k8s_volume_capacity', async () => {
+		render(
+			<QueryClientProvider client={queryClient}>
+				<Provider store={store}>
+					<MemoryRouter>
+						<K8sVolumesList
+							isFiltersVisible={false}
+							handleFilterVisibilityChange={jest.fn()}
+							quickFiltersLastUpdated={-1}
+						/>
+					</MemoryRouter>
+				</Provider>
+			</QueryClientProvider>,
+		);
+
+		await waitFor(() => {
+			expect(requestsMade.length).toBeGreaterThan(0);
+		});
+
+		// Find the attribute_keys request
+		const attributeKeysRequest = requestsMade.find((req) =>
+			req.url.includes('/autocomplete/attribute_keys'),
+		);
+
+		expect(attributeKeysRequest).toBeDefined();
+
+		const aggregateAttribute = attributeKeysRequest?.params.get(
+			'aggregateAttribute',
+		);
+
+		expect(aggregateAttribute).toBe('k8s_volume_capacity');
+	});
+
+	it('should call aggregate keys API with k8s.volume.capacity when dotMetrics enabled', async () => {
+		jest
+			.spyOn(await import('providers/App/App'), 'useAppContext')
+			.mockReturnValue({
+				featureFlags: [
+					{
+						name: FeatureKeys.DOT_METRICS_ENABLED,
+						active: true,
+						usage: 0,
+						usage_limit: 0,
+						route: '',
+					},
+				],
+				user: { role: 'ADMIN' } as IUser,
+				activeLicense: (null as unknown) as LicenseResModel,
+			} as IAppContext);
+
+		render(
+			<QueryClientProvider client={queryClient}>
+				<Provider store={store}>
+					<MemoryRouter>
+						<K8sVolumesList
+							isFiltersVisible={false}
+							handleFilterVisibilityChange={jest.fn()}
+							quickFiltersLastUpdated={-1}
+						/>
+					</MemoryRouter>
+				</Provider>
+			</QueryClientProvider>,
+		);
+
+		await waitFor(() => {
+			expect(requestsMade.length).toBeGreaterThan(0);
+		});
+
+		const attributeKeysRequest = requestsMade.find((req) =>
+			req.url.includes('/autocomplete/attribute_keys'),
+		);
+
+		expect(attributeKeysRequest).toBeDefined();
+
+		const aggregateAttribute = attributeKeysRequest?.params.get(
+			'aggregateAttribute',
+		);
+
+		expect(aggregateAttribute).toBe('k8s.volume.capacity');
+	});
+});

frontend/src/types/api/alerts/def.ts

@@ -56,8 +56,8 @@ export interface AlertRuleStats {
 	totalPastTriggers: number;
 	currentTriggersSeries: CurrentTriggersSeries;
 	pastTriggersSeries: CurrentTriggersSeries | null;
-	currentAvgResolutionTime: number;
-	pastAvgResolutionTime: number;
+	currentAvgResolutionTime: string;
+	pastAvgResolutionTime: string;
 	currentAvgResolutionTimeSeries: CurrentTriggersSeries;
 	pastAvgResolutionTimeSeries: any | null;
 }

frontend/src/utils/timeUtils.ts

@@ -112,6 +112,12 @@ export function formatEpochTimestamp(epoch: number): string {
  */
 
 export function formatTime(seconds: number): string {
+	seconds = +seconds;
+
+	if (Number.isNaN(seconds)) {
+		return '-';
+	}
+
 	const days = seconds / 86400;
 
 	if (days >= 1) {

pkg/query-service/app/clickhouseReader/reader.go

@@ -1090,7 +1090,21 @@ func (r *ClickHouseReader) GetWaterfallSpansForTraceWithMetadata(ctx context.Con
 	}
 
 	processingPostCache := time.Now()
-	selectedSpans, uncollapsedSpans, rootServiceName, rootServiceEntryPoint := tracedetail.GetSelectedSpans(req.UncollapsedSpans, req.SelectedSpanID, traceRoots, spanIdToSpanNodeMap, req.IsSelectedSpanIDUnCollapsed)
+	// When req.Limit is 0 (not set by the client),  selectAllSpans is set to false
+	// preserving the old paged behaviour for backward compatibility
+	limit := min(req.Limit, tracedetail.MaxLimitToSelectAllSpans)
+	selectAllSpans := totalSpans <= uint64(limit)
+
+	var (
+		selectedSpans                          []*model.Span
+		uncollapsedSpans                       []string
+		rootServiceName, rootServiceEntryPoint string
+	)
+	if selectAllSpans {
+		selectedSpans, rootServiceName, rootServiceEntryPoint = tracedetail.GetAllSpans(traceRoots)
+	} else {
+		selectedSpans, uncollapsedSpans, rootServiceName, rootServiceEntryPoint = tracedetail.GetSelectedSpans(req.UncollapsedSpans, req.SelectedSpanID, traceRoots, spanIdToSpanNodeMap, req.IsSelectedSpanIDUnCollapsed)
+	}
 	r.logger.Info("getWaterfallSpansForTraceWithMetadata: processing post cache", "duration", time.Since(processingPostCache), "traceID", traceID)
 
 	// convert start timestamp to millis because right now frontend is expecting it in millis
@@ -1103,7 +1117,7 @@ func (r *ClickHouseReader) GetWaterfallSpansForTraceWithMetadata(ctx context.Con
 	}
 
 	response.Spans = selectedSpans
-	response.UncollapsedSpans = uncollapsedSpans
+	response.UncollapsedSpans = uncollapsedSpans // ignoring if all spans are returning
 	response.StartTimestampMillis = startTime / 1000000
 	response.EndTimestampMillis = endTime / 1000000
 	response.TotalSpansCount = totalSpans
@@ -1112,6 +1126,7 @@ func (r *ClickHouseReader) GetWaterfallSpansForTraceWithMetadata(ctx context.Con
 	response.RootServiceEntryPoint = rootServiceEntryPoint
 	response.ServiceNameToTotalDurationMap = serviceNameToTotalDurationMap
 	response.HasMissingSpans = hasMissingSpans
+	response.HasMore = !selectAllSpans
 	return response, nil
 }
 
@@ -3371,8 +3386,8 @@ func (r *ClickHouseReader) GetMetricAggregateAttributes(ctx context.Context, org
 
 	// Query all relevant metric names from time_series_v4, but leave metadata retrieval to cache/db
 	query := fmt.Sprintf(
-		`SELECT DISTINCT metric_name 
-		 FROM %s.%s 
+		`SELECT DISTINCT metric_name
+		 FROM %s.%s
 		 WHERE metric_name ILIKE $1 AND __normalized = $2`,
 		signozMetricDBName, signozTSTableNameV41Day)
 
@@ -3449,8 +3464,8 @@ func (r *ClickHouseReader) GetMeterAggregateAttributes(ctx context.Context, orgI
 	var response v3.AggregateAttributeResponse
 	// Query all relevant metric names from time_series_v4, but leave metadata retrieval to cache/db
 	query := fmt.Sprintf(
-		`SELECT metric_name,type,temporality,is_monotonic 
-		 FROM %s.%s 
+		`SELECT metric_name,type,temporality,is_monotonic
+		 FROM %s.%s
 		 WHERE metric_name ILIKE $1
 		 GROUP BY metric_name,type,temporality,is_monotonic`,
 		signozMeterDBName, signozMeterSamplesName)
@@ -5146,7 +5161,7 @@ func (r *ClickHouseReader) GetOverallStateTransitions(ctx context.Context, ruleI
         state,
         unix_milli AS firing_time
     FROM %s.%s
-    WHERE overall_state = '` + model.StateFiring.String() + `' 
+    WHERE overall_state = '` + model.StateFiring.String() + `'
       AND overall_state_changed = true
       AND rule_id IN ('%s')
 	  AND unix_milli >= %d AND unix_milli <= %d
@@ -5157,7 +5172,7 @@ resolution_events AS (
         state,
         unix_milli AS resolution_time
     FROM %s.%s
-    WHERE overall_state = '` + model.StateInactive.String() + `' 
+    WHERE overall_state = '` + model.StateInactive.String() + `'
       AND overall_state_changed = true
       AND rule_id IN ('%s')
 	  AND unix_milli >= %d AND unix_milli <= %d
@@ -5278,7 +5293,7 @@ WITH firing_events AS (
         state,
         unix_milli AS firing_time
     FROM %s.%s
-    WHERE overall_state = '` + model.StateFiring.String() + `' 
+    WHERE overall_state = '` + model.StateFiring.String() + `'
       AND overall_state_changed = true
       AND rule_id IN ('%s')
 	  AND unix_milli >= %d AND unix_milli <= %d
@@ -5289,7 +5304,7 @@ resolution_events AS (
         state,
         unix_milli AS resolution_time
     FROM %s.%s
-    WHERE overall_state = '` + model.StateInactive.String() + `' 
+    WHERE overall_state = '` + model.StateInactive.String() + `'
       AND overall_state_changed = true
       AND rule_id IN ('%s')
 	  AND unix_milli >= %d AND unix_milli <= %d
@@ -5335,7 +5350,7 @@ WITH firing_events AS (
         state,
         unix_milli AS firing_time
     FROM %s.%s
-    WHERE overall_state = '` + model.StateFiring.String() + `' 
+    WHERE overall_state = '` + model.StateFiring.String() + `'
       AND overall_state_changed = true
       AND rule_id IN ('%s')
 	  AND unix_milli >= %d AND unix_milli <= %d
@@ -5346,7 +5361,7 @@ resolution_events AS (
         state,
         unix_milli AS resolution_time
     FROM %s.%s
-    WHERE overall_state = '` + model.StateInactive.String() + `' 
+    WHERE overall_state = '` + model.StateInactive.String() + `'
       AND overall_state_changed = true
       AND rule_id IN ('%s')
 	  AND unix_milli >= %d AND unix_milli <= %d
@@ -5608,7 +5623,7 @@ func (r *ClickHouseReader) GetMetricsDataPoints(ctx context.Context, metricName
 		instrumentationtypes.CodeNamespace:    "clickhouse-reader",
 		instrumentationtypes.CodeFunctionName: "GetMetricsDataPoints",
 	})
-	query := fmt.Sprintf(`SELECT 
+	query := fmt.Sprintf(`SELECT
     sum(count) as data_points
 FROM %s.%s
 WHERE metric_name = ?
@@ -5628,7 +5643,7 @@ func (r *ClickHouseReader) GetMetricsLastReceived(ctx context.Context, metricNam
 		instrumentationtypes.CodeNamespace:    "clickhouse-reader",
 		instrumentationtypes.CodeFunctionName: "GetMetricsLastReceived",
 	})
-	query := fmt.Sprintf(`SELECT 
+	query := fmt.Sprintf(`SELECT
     MAX(unix_milli) AS last_received_time
 FROM %s.%s
 WHERE metric_name = ?
@@ -5639,7 +5654,7 @@ WHERE metric_name = ?
 	if err != nil {
 		return 0, &model.ApiError{Typ: "ClickHouseError", Err: err}
 	}
-	query = fmt.Sprintf(`SELECT 
+	query = fmt.Sprintf(`SELECT
     MAX(unix_milli) AS last_received_time
 FROM %s.%s
 WHERE metric_name = ? and unix_milli > ?
@@ -5658,7 +5673,7 @@ func (r *ClickHouseReader) GetTotalTimeSeriesForMetricName(ctx context.Context,
 		instrumentationtypes.CodeNamespace:    "clickhouse-reader",
 		instrumentationtypes.CodeFunctionName: "GetTotalTimeSeriesForMetricName",
 	})
-	query := fmt.Sprintf(`SELECT 
+	query := fmt.Sprintf(`SELECT
     uniq(fingerprint) AS timeSeriesCount
 FROM %s.%s
 WHERE metric_name = ?;`, signozMetricDBName, signozTSTableNameV41Week)
@@ -5690,7 +5705,7 @@ func (r *ClickHouseReader) GetAttributesForMetricName(ctx context.Context, metri
 	}
 
 	const baseQueryTemplate = `
-SELECT 
+SELECT
     kv.1 AS key,
     arrayMap(x -> trim(BOTH '"' FROM x), groupUniqArray(1000)(kv.2)) AS values,
     length(groupUniqArray(10000)(kv.2)) AS valueCount
@@ -5799,7 +5814,7 @@ func (r *ClickHouseReader) ListSummaryMetrics(ctx context.Context, orgID valuer.
 	sampleTable, countExp := utils.WhichSampleTableToUse(req.Start, req.End)
 
 	metricsQuery := fmt.Sprintf(
-		`SELECT 
+		`SELECT
 		    t.metric_name AS metric_name,
 		    ANY_VALUE(t.description) AS description,
 		    ANY_VALUE(t.type) AS metric_type,
@@ -5864,11 +5879,11 @@ func (r *ClickHouseReader) ListSummaryMetrics(ctx context.Context, orgID valuer.
 
 	if whereClause != "" {
 		sb.WriteString(fmt.Sprintf(
-			`SELECT 
+			`SELECT
 				s.samples,
 				s.metric_name
 			FROM (
-				SELECT 
+				SELECT
 					dm.metric_name,
 					%s AS samples
 				FROM %s.%s AS dm
@@ -5898,11 +5913,11 @@ func (r *ClickHouseReader) ListSummaryMetrics(ctx context.Context, orgID valuer.
 	} else {
 		// If no filters, it is a simpler query.
 		sb.WriteString(fmt.Sprintf(
-			`SELECT 
+			`SELECT
         s.samples,
         s.metric_name
     FROM (
-        SELECT 
+        SELECT
             metric_name,
             %s AS samples
         FROM %s.%s
@@ -6007,16 +6022,16 @@ func (r *ClickHouseReader) GetMetricsTimeSeriesPercentage(ctx context.Context, r
 
 	// Construct the query without backticks
 	query := fmt.Sprintf(`
-		SELECT 
+		SELECT
 			metric_name,
 			total_value,
 			(total_value * 100.0 / total_time_series) AS percentage
 		FROM (
-			SELECT 
+			SELECT
 					metric_name,
 					uniq(fingerprint) AS total_value,
-					(SELECT uniq(fingerprint) 
-					 FROM %s.%s 
+					(SELECT uniq(fingerprint)
+					 FROM %s.%s
 					 WHERE unix_milli BETWEEN ? AND ? AND __normalized = ?) AS total_time_series
 				FROM %s.%s
 				WHERE unix_milli BETWEEN ? AND ? AND NOT startsWith(metric_name, 'signoz') AND __normalized = ? %s
@@ -6092,7 +6107,7 @@ func (r *ClickHouseReader) GetMetricsSamplesPercentage(ctx context.Context, req
 
 	queryLimit := 50 + req.Limit
 	metricsQuery := fmt.Sprintf(
-		`SELECT 
+		`SELECT
 		    ts.metric_name AS metric_name,
 		    uniq(ts.fingerprint) AS timeSeries
 		FROM %s.%s AS ts
@@ -6149,13 +6164,13 @@ func (r *ClickHouseReader) GetMetricsSamplesPercentage(ctx context.Context, req
 			FROM %s.%s
 			WHERE unix_milli BETWEEN ? AND ?
 		)
-		SELECT 
+		SELECT
 			s.samples,
 			s.metric_name,
 			COALESCE((s.samples * 100.0 / t.total_samples), 0) AS percentage
-		FROM 
+		FROM
 		(
-			SELECT 
+			SELECT
 				dm.metric_name,
 				%s AS samples
 			FROM %s.%s AS dm`,
@@ -6176,7 +6191,7 @@ func (r *ClickHouseReader) GetMetricsSamplesPercentage(ctx context.Context, req
 	if whereClause != "" {
 		sb.WriteString(fmt.Sprintf(
 			` AND dm.fingerprint IN (
-				SELECT ts.fingerprint 
+				SELECT ts.fingerprint
 				FROM %s.%s AS ts
 				WHERE ts.metric_name IN (%s)
 				AND unix_milli BETWEEN ? AND ?
@@ -6247,7 +6262,7 @@ func (r *ClickHouseReader) GetNameSimilarity(ctx context.Context, req *metrics_e
 	}
 
 	query := fmt.Sprintf(`
-		SELECT 
+		SELECT
 			metric_name,
 			any(type) as type,
 		    any(temporality) as temporality,
@@ -6306,7 +6321,7 @@ func (r *ClickHouseReader) GetAttributeSimilarity(ctx context.Context, req *metr
 
 	// Get target labels
 	extractedLabelsQuery := fmt.Sprintf(`
-		SELECT 
+		SELECT
 			kv.1 AS label_key,
 			topK(10)(JSONExtractString(kv.2)) AS label_values
 		FROM %s.%s
@@ -6350,12 +6365,12 @@ func (r *ClickHouseReader) GetAttributeSimilarity(ctx context.Context, req *metr
 	priorityListString := strings.Join(priorityList, ", ")
 
 	candidateLabelsQuery := fmt.Sprintf(`
-		WITH 
-			arrayDistinct([%s]) AS filter_keys,     
+		WITH
+			arrayDistinct([%s]) AS filter_keys,
 			arrayDistinct([%s]) AS filter_values,
 			[%s] AS priority_pairs_input,
 			%d AS priority_multiplier
-		SELECT 
+		SELECT
 			metric_name,
 			any(type) as type,
 			any(temporality) as temporality,
@@ -6461,17 +6476,17 @@ func (r *ClickHouseReader) GetMetricsAllResourceAttributes(ctx context.Context,
 		instrumentationtypes.CodeFunctionName: "GetMetricsAllResourceAttributes",
 	})
 	start, end, attTable, _ := utils.WhichAttributesTableToUse(start, end)
-	query := fmt.Sprintf(`SELECT 
-    key, 
+	query := fmt.Sprintf(`SELECT
+    key,
     count(distinct value) AS distinct_value_count
 FROM (
     SELECT key, value
     FROM %s.%s
-    ARRAY JOIN 
+    ARRAY JOIN
         arrayConcat(mapKeys(resource_attributes)) AS key,
         arrayConcat(mapValues(resource_attributes)) AS value
     WHERE unix_milli between ? and ?
-) 
+)
 GROUP BY key
 ORDER BY distinct_value_count DESC;`, signozMetadataDbName, attTable)
 	valueCtx := context.WithValue(ctx, "clickhouse_max_threads", constants.MetricsExplorerClickhouseThreads)
@@ -6618,11 +6633,11 @@ func (r *ClickHouseReader) GetInspectMetricsFingerprints(ctx context.Context, at
 
 	start, end, tsTable, _ := utils.WhichTSTableToUse(req.Start, req.End)
 	query := fmt.Sprintf(`
-        SELECT 
+        SELECT
     arrayDistinct(groupArray(toString(fingerprint))) AS fingerprints
 FROM
 (
-    SELECT 
+    SELECT
         metric_name, labels, fingerprint,
         %s
     FROM %s.%s
@@ -6793,14 +6808,14 @@ func (r *ClickHouseReader) GetUpdatedMetricsMetadata(ctx context.Context, orgID
 	var stillMissing []string
 	if len(missingMetrics) > 0 {
 		metricList := "'" + strings.Join(missingMetrics, "', '") + "'"
-		query := fmt.Sprintf(`SELECT 
+		query := fmt.Sprintf(`SELECT
 						metric_name,
 						argMax(type, created_at) AS type,
 						argMax(description, created_at) AS description,
 						argMax(temporality, created_at) AS temporality,
 						argMax(is_monotonic, created_at) AS is_monotonic,
 						argMax(unit, created_at) AS unit
-					FROM %s.%s 
+					FROM %s.%s
 					WHERE metric_name IN (%s)
 					GROUP BY metric_name;`,
 			signozMetricDBName,
@@ -6848,7 +6863,7 @@ func (r *ClickHouseReader) GetUpdatedMetricsMetadata(ctx context.Context, orgID
 	if len(stillMissing) > 0 {
 		metricList := "'" + strings.Join(stillMissing, "', '") + "'"
 		query := fmt.Sprintf(`SELECT DISTINCT metric_name, type, description, temporality, is_monotonic, unit
-			FROM %s.%s 
+			FROM %s.%s
 			WHERE metric_name IN (%s)`, signozMetricDBName, signozTSTableNameV4, metricList)
 		valueCtx := context.WithValue(ctx, "clickhouse_max_threads", constants.MetricsExplorerClickhouseThreads)
 		rows, err := r.db.Query(valueCtx, query)

pkg/query-service/app/traces/tracedetail/waterfall.go

@@ -1,6 +1,7 @@
 package tracedetail
 
 import (
+	"maps"
 	"slices"
 	"sort"
 
@@ -9,6 +10,9 @@ import (
 
 var (
 	SPAN_LIMIT_PER_REQUEST_FOR_WATERFALL float64 = 500
+
+	maxDepthForSelectedSpanChildren int  = 5
+	MaxLimitToSelectAllSpans        uint = 10_000
 )
 
 type Interval struct {
@@ -63,26 +67,22 @@ func findIndexForSelectedSpanFromPreOrder(spans []*model.Span, selectedSpanId st
 	return selectedSpanIndex
 }
 
-func getPathFromRootToSelectedSpanId(node *model.Span, selectedSpanId string, uncollapsedSpans []string, isSelectedSpanIDUnCollapsed bool) (bool, []string) {
+func getPathFromRootToSelectedSpanId(node *model.Span, selectedSpanId string) (bool, []string) {
 	spansFromRootToNode := []string{}
 
+	spansFromRootToNode = append(spansFromRootToNode, node.SpanID)
 	if node.SpanID == selectedSpanId {
-		if isSelectedSpanIDUnCollapsed && !slices.Contains(uncollapsedSpans, node.SpanID) {
-			spansFromRootToNode = append(spansFromRootToNode, node.SpanID)
-		}
 		return true, spansFromRootToNode
 	}
 
 	isPresentInSubtreeForTheNode := false
 	for _, child := range node.Children {
-		isPresentInThisSubtree, _spansFromRootToNode := getPathFromRootToSelectedSpanId(child, selectedSpanId, uncollapsedSpans, isSelectedSpanIDUnCollapsed)
+		isPresentInThisSubtree, _spansFromRootToNode := getPathFromRootToSelectedSpanId(child, selectedSpanId)
 		// if the interested node is present in the given subtree then add the span node to uncollapsed node list
 		if isPresentInThisSubtree {
-			if !slices.Contains(uncollapsedSpans, node.SpanID) {
-				spansFromRootToNode = append(spansFromRootToNode, node.SpanID)
-			}
 			isPresentInSubtreeForTheNode = true
 			spansFromRootToNode = append(spansFromRootToNode, _spansFromRootToNode...)
+			break
 		}
 	}
 	return isPresentInSubtreeForTheNode, spansFromRootToNode
@@ -92,12 +92,23 @@ func getPathFromRootToSelectedSpanId(node *model.Span, selectedSpanId string, un
 // throughout the recursion. Per-call state (level, isPartOfPreOrder, etc.)
 // is passed as direct arguments.
 type traverseOpts struct {
-	uncollapsedSpans []string
-	selectedSpanID   string
+	uncollapsedSpans          map[string]struct{}
+	selectedSpanID            string
+	isSelectedSpanUncollapsed bool
+	selectAll                 bool
 }
 
-func traverseTrace(span *model.Span, opts traverseOpts, level uint64, isPartOfPreOrder bool, hasSibling bool) []*model.Span {
+func traverseTrace(
+	span *model.Span,
+	opts traverseOpts,
+	level uint64,
+	isPartOfPreOrder bool,
+	hasSibling bool,
+	autoExpandDepth int,
+) ([]*model.Span, []string) {
+
 	preOrderTraversal := []*model.Span{}
+	autoExpandedSpans := []string{}
 
 	// sort the children to maintain the order across requests
 	sort.Slice(span.Children, func(i, j int) bool {
@@ -134,16 +145,36 @@ func traverseTrace(span *model.Span, opts traverseOpts, level uint64, isPartOfPr
 		preOrderTraversal = append(preOrderTraversal, &nodeWithoutChildren)
 	}
 
-	isAlreadyUncollapsed := slices.Contains(opts.uncollapsedSpans, span.SpanID)
+	remainingAutoExpandDepth := 0
+	if span.SpanID == opts.selectedSpanID && opts.isSelectedSpanUncollapsed {
+		remainingAutoExpandDepth = maxDepthForSelectedSpanChildren
+	} else if autoExpandDepth > 0 {
+		remainingAutoExpandDepth = autoExpandDepth - 1
+	}
+
+	_, isAlreadyUncollapsed := opts.uncollapsedSpans[span.SpanID]
 	for index, child := range span.Children {
-		_childTraversal := traverseTrace(child, opts, level+1, isPartOfPreOrder && isAlreadyUncollapsed, index != (len(span.Children)-1))
+		// A child is included in the pre-order output if its parent is uncollapsed
+		// OR if the child falls within MAX_DEPTH_FOR_SELECTED_SPAN_CHILDREN levels
+		// below the selected span.
+		isChildWithinMaxDepth := remainingAutoExpandDepth > 0
+		childIsPartOfPreOrder := opts.selectAll || (isPartOfPreOrder && (isAlreadyUncollapsed || isChildWithinMaxDepth))
+
+		if isPartOfPreOrder && isChildWithinMaxDepth && !isAlreadyUncollapsed {
+			if !slices.Contains(autoExpandedSpans, span.SpanID) {
+				autoExpandedSpans = append(autoExpandedSpans, span.SpanID)
+			}
+		}
+
+		_childTraversal, _autoExpanded := traverseTrace(child, opts, level+1, childIsPartOfPreOrder, index != (len(span.Children)-1), remainingAutoExpandDepth)
 		preOrderTraversal = append(preOrderTraversal, _childTraversal...)
+		autoExpandedSpans = append(autoExpandedSpans, _autoExpanded...)
 		nodeWithoutChildren.SubTreeNodeCount += child.SubTreeNodeCount + 1
 		span.SubTreeNodeCount += child.SubTreeNodeCount + 1
 	}
 
 	nodeWithoutChildren.SubTreeNodeCount += 1
-	return preOrderTraversal
+	return preOrderTraversal, autoExpandedSpans
 
 }
 
@@ -169,19 +200,36 @@ func GetSelectedSpans(uncollapsedSpans []string, selectedSpanID string, traceRoo
 
 	var preOrderTraversal = make([]*model.Span, 0)
 	var rootServiceName, rootServiceEntryPoint string
-	updatedUncollapsedSpans := uncollapsedSpans
+
+	// create a map of uncollapsed spans for quick lookup
+	uncollapsedSpanMap := make(map[string]struct{})
+	for _, spanID := range uncollapsedSpans {
+		uncollapsedSpanMap[spanID] = struct{}{}
+	}
 
 	selectedSpanIndex := -1
 	for _, rootSpanID := range traceRoots {
 		if rootNode, exists := spanIdToSpanNodeMap[rootSpanID.SpanID]; exists {
-			_, spansFromRootToNode := getPathFromRootToSelectedSpanId(rootNode, selectedSpanID, updatedUncollapsedSpans, isSelectedSpanIDUnCollapsed)
-			updatedUncollapsedSpans = append(updatedUncollapsedSpans, spansFromRootToNode...)
+			present, spansFromRootToNode := getPathFromRootToSelectedSpanId(rootNode, selectedSpanID)
+			if present {
+				for _, spanID := range spansFromRootToNode {
+					if selectedSpanID == spanID && !isSelectedSpanIDUnCollapsed {
+						continue
+					}
+					uncollapsedSpanMap[spanID] = struct{}{}
+				}
+			}
 
 			opts := traverseOpts{
-				uncollapsedSpans: updatedUncollapsedSpans,
-				selectedSpanID:   selectedSpanID,
+				uncollapsedSpans:          uncollapsedSpanMap,
+				selectedSpanID:            selectedSpanID,
+				isSelectedSpanUncollapsed: isSelectedSpanIDUnCollapsed,
+			}
+			_preOrderTraversal, _autoExpanded := traverseTrace(rootNode, opts, 0, true, false, 0)
+			// Merge auto-expanded spans into updatedUncollapsedSpans for returning in response
+			for _, spanID := range _autoExpanded {
+				uncollapsedSpanMap[spanID] = struct{}{}
 			}
-			_preOrderTraversal := traverseTrace(rootNode, opts, 0, true, false)
 			_selectedSpanIndex := findIndexForSelectedSpanFromPreOrder(_preOrderTraversal, selectedSpanID)
 
 			if _selectedSpanIndex != -1 {
@@ -223,5 +271,17 @@ func GetSelectedSpans(uncollapsedSpans []string, selectedSpanID string, traceRoo
 		startIndex = 0
 	}
 
-	return preOrderTraversal[startIndex:endIndex], updatedUncollapsedSpans, rootServiceName, rootServiceEntryPoint
+	return preOrderTraversal[startIndex:endIndex], slices.Collect(maps.Keys(uncollapsedSpanMap)), rootServiceName, rootServiceEntryPoint
+}
+
+func GetAllSpans(traceRoots []*model.Span) (spans []*model.Span, rootServiceName, rootEntryPoint string) {
+	if len(traceRoots) > 0 {
+		rootServiceName = traceRoots[0].ServiceName
+		rootEntryPoint = traceRoots[0].Name
+	}
+	for _, root := range traceRoots {
+		childSpans, _ := traverseTrace(root, traverseOpts{selectAll: true}, 0, true, false, 0)
+		spans = append(spans, childSpans...)
+	}
+	return
 }

pkg/query-service/app/traces/tracedetail/waterfall_test.go

@@ -81,28 +81,6 @@ func TestGetSelectedSpans_MultipleRoots(t *testing.T) {
 	assert.Equal(t, "root1-op", entryPoint, "metadata comes from first root")
 }
 
-// isSelectedSpanIDUnCollapsed=true opens only the selected span's direct children,
-// not deeper descendants.
-//
-//	root → selected (expanded)
-//	          ├─ child1 ✓
-//	          │    └─ grandchild ✗  (only one level opened)
-//	          └─ child2 ✓
-func TestGetSelectedSpans_ExpandedSelectedSpan(t *testing.T) {
-	root := mkSpan("root", "svc",
-		mkSpan("selected", "svc",
-			mkSpan("child1", "svc", mkSpan("grandchild", "svc")),
-			mkSpan("child2", "svc"),
-		),
-	)
-	spanMap := buildSpanMap(root)
-	spans, _, _, _ := GetSelectedSpans([]string{}, "selected", []*model.Span{root}, spanMap, true)
-
-	// root and selected are on the auto-uncollapsed path; child1/child2 are direct
-	// children of the expanded selected span; grandchild stays hidden.
-	assert.Equal(t, []string{"root", "selected", "child1", "child2"}, spanIDs(spans))
-}
-
 // Multiple spans uncollapsed simultaneously: children of all uncollapsed spans
 // are visible at once.
 //
@@ -183,7 +161,7 @@ func TestGetSelectedSpans_PathReturnedInUncollapsed(t *testing.T) {
 	spanMap := buildSpanMap(root)
 	spans, uncollapsed, _, _ := GetSelectedSpans([]string{}, "selected", []*model.Span{root}, spanMap, false)
 
-	assert.Equal(t, []string{"root", "parent"}, uncollapsed)
+	assert.ElementsMatch(t, []string{"root", "parent"}, uncollapsed)
 	assert.Equal(t, []string{"root", "parent", "selected"}, spanIDs(spans))
 }
 
@@ -206,7 +184,7 @@ func TestGetSelectedSpans_SiblingsNotExpanded(t *testing.T) {
 	// children of root sort alphabetically: parent < unrelated; unrelated-child stays hidden
 	assert.Equal(t, []string{"root", "parent", "selected", "unrelated"}, spanIDs(spans))
 	// only the path nodes are tracked as uncollapsed — unrelated is not
-	assert.Equal(t, []string{"root", "parent"}, uncollapsed)
+	assert.ElementsMatch(t, []string{"root", "parent"}, uncollapsed)
 }
 
 // An unknown selectedSpanID must not panic; returns a window from index 0.
@@ -320,6 +298,119 @@ func TestGetSelectedSpans_WindowShiftsAtStart(t *testing.T) {
 	assert.Equal(t, "span10", spans[10].SpanID, "selected span still in window")
 }
 
+// Auto-expanded span IDs from ALL branches are returned in
+// updatedUncollapsedSpans. Only internal nodes (spans with children) are
+// tracked — leaf spans are never added.
+//
+//	root (selected)
+//	  ├─ childA (internal ✓)
+//	  │    └─ grandchildA (internal ✓)
+//	  │         └─ leafA (leaf ✗)
+//	  └─ childB (internal ✓)
+//	       └─ grandchildB (internal ✓)
+//	            └─ leafB (leaf ✗)
+func TestGetSelectedSpans_AutoExpandedSpansReturnedInUncollapsed(t *testing.T) {
+	root := mkSpan("root", "svc",
+		mkSpan("childA", "svc",
+			mkSpan("grandchildA", "svc",
+				mkSpan("leafA", "svc"),
+			),
+		),
+		mkSpan("childB", "svc",
+			mkSpan("grandchildB", "svc",
+				mkSpan("leafB", "svc"),
+			),
+		),
+	)
+	spanMap := buildSpanMap(root)
+	_, uncollapsed, _, _ := GetSelectedSpans([]string{}, "root", []*model.Span{root}, spanMap, true)
+
+	// all internal nodes across both branches must be tracked
+	assert.Contains(t, uncollapsed, "root")
+	assert.Contains(t, uncollapsed, "childA", "internal node depth 1, branch A")
+	assert.Contains(t, uncollapsed, "childB", "internal node depth 1, branch B")
+	assert.Contains(t, uncollapsed, "grandchildA", "internal node depth 2, branch A")
+	assert.Contains(t, uncollapsed, "grandchildB", "internal node depth 2, branch B")
+	// leaves have no children to show — never added to uncollapsedSpans
+	assert.NotContains(t, uncollapsed, "leafA", "leaf spans are never added to uncollapsedSpans")
+	assert.NotContains(t, uncollapsed, "leafB", "leaf spans are never added to uncollapsedSpans")
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// maxDepthForSelectedSpanChildren boundary tests
+// ─────────────────────────────────────────────────────────────────────────────
+
+// Depth is measured from the selected span, not the trace root.
+// Ancestors appear via the path-to-root logic, not the depth limit.
+// Each depth level has two children to confirm the limit is enforced on all
+// branches, not just the first.
+//
+//	root
+//	  └─ A                           ancestor ✓ (path-to-root)
+//	       └─ selected
+//	            ├─ d1a               depth 1 ✓
+//	            │    ├─ d2a          depth 2 ✓
+//	            │    │    ├─ d3a     depth 3 ✓
+//	            │    │    │    ├─ d4a   depth 4 ✓
+//	            │    │    │    │    ├─ d5a  depth 5 ✓
+//	            │    │    │    │    │    └─ d6a  depth 6 ✗
+//	            │    │    │    │    └─ d5b  depth 5 ✓
+//	            │    │    │    └─ d4b   depth 4 ✓
+//	            │    │    └─ d3b     depth 3 ✓
+//	            │    └─ d2b          depth 2 ✓
+//	            └─ d1b               depth 1 ✓
+func TestGetSelectedSpans_DepthCountedFromSelectedSpan(t *testing.T) {
+	selected := mkSpan("selected", "svc",
+		mkSpan("d1a", "svc",
+			mkSpan("d2a", "svc",
+				mkSpan("d3a", "svc",
+					mkSpan("d4a", "svc",
+						mkSpan("d5a", "svc",
+							mkSpan("d6a", "svc"), // depth 6 — excluded
+						),
+						mkSpan("d5b", "svc"), // depth 5 — included
+					),
+					mkSpan("d4b", "svc"), // depth 4 — included
+				),
+				mkSpan("d3b", "svc"), // depth 3 — included
+			),
+			mkSpan("d2b", "svc"), // depth 2 — included
+		),
+		mkSpan("d1b", "svc"), // depth 1 — included
+	)
+	root := mkSpan("root", "svc", mkSpan("A", "svc", selected))
+
+	spanMap := buildSpanMap(root)
+	spans, _, _, _ := GetSelectedSpans([]string{}, "selected", []*model.Span{root}, spanMap, true)
+	ids := spanIDs(spans)
+
+	assert.Contains(t, ids, "root", "ancestor shown via path-to-root")
+	assert.Contains(t, ids, "A", "ancestor shown via path-to-root")
+	for _, id := range []string{"d1a", "d1b", "d2a", "d2b", "d3a", "d3b", "d4a", "d4b", "d5a", "d5b"} {
+		assert.Contains(t, ids, id, "depth ≤ 5 — must be included")
+	}
+	assert.NotContains(t, ids, "d6a", "depth 6 > limit — excluded")
+}
+
+func TestGetAllSpans(t *testing.T) {
+	root := mkSpan("root", "svc",
+		mkSpan("childA", "svc",
+			mkSpan("grandchildA", "svc",
+				mkSpan("leafA", "svc2"),
+			),
+		),
+		mkSpan("childB", "svc3",
+			mkSpan("grandchildB", "svc",
+				mkSpan("leafB", "svc2"),
+			),
+		),
+	)
+	spans, rootServiceName, rootEntryPoint := GetAllSpans([]*model.Span{root})
+	assert.ElementsMatch(t, spanIDs(spans), []string{"root", "childA", "grandchildA", "leafA", "childB", "grandchildB", "leafB"})
+	assert.Equal(t, rootServiceName, "svc")
+	assert.Equal(t, rootEntryPoint, "root-op")
+}
+
 func mkSpan(id, service string, children ...*model.Span) *model.Span {
 	return &model.Span{
 		SpanID:      id,

pkg/query-service/model/queryParams.go

@@ -333,6 +333,7 @@ type GetWaterfallSpansForTraceWithMetadataParams struct {
 	SelectedSpanID              string   `json:"selectedSpanId"`
 	IsSelectedSpanIDUnCollapsed bool     `json:"isSelectedSpanIDUnCollapsed"`
 	UncollapsedSpans            []string `json:"uncollapsedSpans"`
+	Limit                       uint     `json:"limit"`
 }
 
 type GetFlamegraphSpansForTraceParams struct {

pkg/query-service/model/response.go

@@ -329,6 +329,7 @@ type GetWaterfallSpansForTraceWithMetadataResponse struct {
 	HasMissingSpans               bool              `json:"hasMissingSpans"`
 	// this is needed for frontend and query service sync
 	UncollapsedSpans []string `json:"uncollapsedSpans"`
+	HasMore          bool     `json:"hasMore"`
 }
 
 type GetFlamegraphSpansForTraceResponse struct {

pkg/types/querybuildertypes/querybuildertypesv5/functions.go

@@ -102,6 +102,10 @@ func (fn FunctionName) Validate() error {
 
 // ApplyFunction applies the given function to the result data
 func ApplyFunction(fn Function, result *TimeSeries) *TimeSeries {
+	if len(result.Values) == 0 {
+		return result
+	}
+
 	// Extract the function name and arguments
 	name := fn.Name
 	args := fn.Args

pkg/types/querybuildertypes/querybuildertypesv5/functions_test.go

@@ -599,6 +599,14 @@ func TestApplyFunction(t *testing.T) {
 		values   []float64
 		want     []float64
 	}{
+		{
+			name: "test with empty series",
+			function: Function{
+				Name: FunctionNameRunningDiff,
+			},
+			values: []float64{},
+			want:   []float64{},
+		},
 		{
 			name: "cutOffMin function",
 			function: Function{