test: metrics application test are added (#4137)

* test: metrics application test are added

* fix: getTopOperationList is moved under __mocks__

frontend/src/container/MetricsApplication/__mocks__/getTopOperation.ts

@@ -0,0 +1,19 @@
+import { TopOperationList } from '../TopOperationsTable';
+
+interface TopOperation {
+	numCalls: number;
+	errorCount: number;
+}
+
+export const getTopOperationList = ({
+	errorCount,
+	numCalls,
+}: TopOperation): TopOperationList =>
+	({
+		p50: 0,
+		errorCount,
+		name: 'test',
+		numCalls,
+		p95: 0,
+		p99: 0,
+	} as TopOperationList);

frontend/src/container/MetricsApplication/utils.test.ts

@@ -0,0 +1,70 @@
+import { getTopOperationList } from './__mocks__/getTopOperation';
+import { TopOperationList } from './TopOperationsTable';
+import {
+	convertedTracesToDownloadData,
+	getErrorRate,
+	getNearestHighestBucketValue,
+} from './utils';
+
+describe('Error Rate', () => {
+	test('should return correct error rate', () => {
+		const list: TopOperationList = getTopOperationList({
+			errorCount: 10,
+			numCalls: 100,
+		});
+
+		expect(getErrorRate(list)).toBe(10);
+	});
+
+	test('should handle no errors gracefully', () => {
+		const list = getTopOperationList({ errorCount: 0, numCalls: 100 });
+		expect(getErrorRate(list)).toBe(0);
+	});
+
+	test('should handle zero calls', () => {
+		const list = getTopOperationList({ errorCount: 0, numCalls: 0 });
+		expect(getErrorRate(list)).toBe(0);
+	});
+});
+
+describe('getNearestHighestBucketValue', () => {
+	test('should return nearest higher bucket value', () => {
+		expect(getNearestHighestBucketValue(50, [10, 20, 30, 40, 60, 70])).toBe('60');
+	});
+
+	test('should return +Inf for value higher than any bucket', () => {
+		expect(getNearestHighestBucketValue(80, [10, 20, 30, 40, 60, 70])).toBe(
+			'+Inf',
+		);
+	});
+
+	test('should return the first bucket for value lower than all buckets', () => {
+		expect(getNearestHighestBucketValue(5, [10, 20, 30, 40, 60, 70])).toBe('10');
+	});
+});
+
+describe('convertedTracesToDownloadData', () => {
+	test('should convert trace data correctly', () => {
+		const data = [
+			{
+				name: 'op1',
+				p50: 50000000,
+				p95: 95000000,
+				p99: 99000000,
+				numCalls: 100,
+				errorCount: 10,
+			},
+		];
+
+		expect(convertedTracesToDownloadData(data)).toEqual([
+			{
+				Name: 'op1',
+				'P50 (in ms)': '50.00',
+				'P95 (in ms)': '95.00',
+				'P99 (in ms)': '99.00',
+				'Number of calls': '100',
+				'Error Rate (%)': '10.00',
+			},
+		]);
+	});
+});

frontend/src/container/MetricsApplication/utils.ts

@@ -5,8 +5,12 @@ import history from 'lib/history';
 import { TopOperationList } from './TopOperationsTable';
 import { NavigateToTraceProps } from './types';
 
-export const getErrorRate = (list: TopOperationList): number =>
-	(list.errorCount / list.numCalls) * 100;
+export const getErrorRate = (list: TopOperationList): number => {
+	if (list.errorCount === 0 && list.numCalls === 0) {
+		return 0;
+	}
+	return (list.errorCount / list.numCalls) * 100;
+};
 
 export const navigateToTrace = ({
 	servicename,