Add performance deltas between app deployments on Merge Request widget

app/assets/javascripts/lib/utils/number_utils.js

@@ -42,3 +42,13 @@ export function formatRelevantDigits(number) {
 export function bytesToKiB(number) {
   return number / BYTES_IN_KIB;
 }
+
+/**
+ * Utility function that calculates MiB of the given bytes.
+ *
+ * @param  {Number} number bytes
+ * @return {Number}        MiB
+ */
+export function bytesToMiB(number) {
+  return number / (BYTES_IN_KIB * BYTES_IN_KIB);
+}

app/assets/javascripts/vue_merge_request_widget/components/mr_widget_memory_usage.js

 import statusCodes from '~/lib/utils/http_status';
+import { bytesToMiB } from '~/lib/utils/number_utils';
+
 import MemoryGraph from '../../vue_shared/components/memory_graph';
 import MRWidgetService from '../services/mr_widget_service';
 
@@ -9,8 +11,8 @@ export default {
   },
   data() {
     return {
-      // memoryFrom: 0,
-      // memoryTo: 0,
+      memoryFrom: 0,
+      memoryTo: 0,
       memoryMetrics: [],
       deploymentTime: 0,
       hasMetrics: false,
@@ -35,18 +37,38 @@ export default {
     shouldShowMetricsUnavailable() {
       return !this.loadingMetrics && !this.hasMetrics && !this.loadFailed;
     },
+    memoryChangeType() {
+      const memoryTo = Number(this.memoryTo);
+      const memoryFrom = Number(this.memoryFrom);
+
+      if (memoryTo > memoryFrom) {
+        return 'increased';
+      } else if (memoryTo < memoryFrom) {
+        return 'decreased';
+      }
+
+      return 'unchanged';
+    },
   },
   methods: {
+    getMegabytes(bytesString) {
+      const valueInBytes = Number(bytesString).toFixed(2);
+      return (bytesToMiB(valueInBytes)).toFixed(2);
+    },
     computeGraphData(metrics, deploymentTime) {
       this.loadingMetrics = false;
-      const { memory_values } = metrics;
-      // if (memory_previous.length > 0) {
-      //   this.memoryFrom = Number(memory_previous[0].value[1]).toFixed(2);
-      // }
-      //
-      // if (memory_current.length > 0) {
-      //   this.memoryTo = Number(memory_current[0].value[1]).toFixed(2);
-      // }
+      const { memory_before, memory_after, memory_values } = metrics;
+
+      // Both `memory_before` and `memory_after` objects
+      // have peculiar structure where accessing only a specific
+      // index yeilds correct value that we can use to show memory delta.
+      if (memory_before.length > 0) {
+        this.memoryFrom = this.getMegabytes(memory_before[0].value[1]);
+      }
+
+      if (memory_after.length > 0) {
+        this.memoryTo = this.getMegabytes(memory_after[0].value[1]);
+      }
 
       if (memory_values.length > 0) {
         this.hasMetrics = true;
@@ -102,7 +124,7 @@ export default {
       <p
         v-if="shouldShowMemoryGraph"
         class="usage-info js-usage-info">
-        Deployment memory usage:
+        Memory usage <b>{{memoryChangeType}}</b> from {{memoryFrom}}MB to {{memoryTo}}MB
       </p>
       <p
         v-if="shouldShowLoadFailure"

changelogs/unreleased/27439-memory-usage-info.yml

+---
+title: Add performance deltas between app deployments on Merge Request widget
+merge_request: 11730
+author:

spec/javascripts/lib/utils/number_utility_spec.js

-import { formatRelevantDigits, bytesToKiB } from '~/lib/utils/number_utils';
+import { formatRelevantDigits, bytesToKiB, bytesToMiB } from '~/lib/utils/number_utils';
 
 describe('Number Utils', () => {
   describe('formatRelevantDigits', () => {
@@ -45,4 +45,11 @@ describe('Number Utils', () => {
       expect(bytesToKiB(1000)).toEqual(0.9765625);
     });
   });
+
+  describe('bytesToMiB', () => {
+    it('calculates MiB for the given bytes', () => {
+      expect(bytesToMiB(1048576)).toEqual(1);
+      expect(bytesToMiB(1000000)).toEqual(0.95367431640625);
+    });
+  });
 });

spec/javascripts/vue_mr_widget/components/mr_widget_memory_usage_spec.js

@@ -7,6 +7,18 @@ const url = '/root/acets-review-apps/environments/15/deployments/1/metrics';
 const metricsMockData = {
   success: true,
   metrics: {
+    memory_before: [
+      {
+        metric: {},
+        value: [1495785220.607, '9572875.906976745'],
+      },
+    ],
+    memory_after: [
+      {
+        metric: {},
+        value: [1495787020.607, '4485853.130206379'],
+      },
+    ],
     memory_values: [
       {
         metric: {},
@@ -39,7 +51,7 @@ const createComponent = () => {
 
 const messages = {
   loadingMetrics: 'Loading deployment statistics.',
-  hasMetrics: 'Deployment memory usage:',
+  hasMetrics: 'Memory usage unchanged from 0MB to 0MB',
   loadFailed: 'Failed to load deployment statistics.',
   metricsUnavailable: 'Deployment statistics are not available currently.',
 };
@@ -89,17 +101,52 @@ describe('MemoryUsage', () => {
     });
   });
 
+  describe('computed', () => {
+    describe('memoryChangeType', () => {
+      it('should return "increased" if memoryFrom value is less than memoryTo value', () => {
+        vm.memoryFrom = 4.28;
+        vm.memoryTo = 9.13;
+
+        expect(vm.memoryChangeType).toEqual('increased');
+      });
+
+      it('should return "decreased" if memoryFrom value is less than memoryTo value', () => {
+        vm.memoryFrom = 9.13;
+        vm.memoryTo = 4.28;
+
+        expect(vm.memoryChangeType).toEqual('decreased');
+      });
+
+      it('should return "unchanged" if memoryFrom value equal to memoryTo value', () => {
+        vm.memoryFrom = 1;
+        vm.memoryTo = 1;
+
+        expect(vm.memoryChangeType).toEqual('unchanged');
+      });
+    });
+  });
+
   describe('methods', () => {
     const { metrics, deployment_time } = metricsMockData;
 
+    describe('getMegabytes', () => {
+      it('should return Megabytes from provided Bytes value', () => {
+        const memoryInBytes = '9572875.906976745';
+
+        expect(vm.getMegabytes(memoryInBytes)).toEqual('9.13');
+      });
+    });
+
     describe('computeGraphData', () => {
       it('should populate sparkline graph', () => {
         vm.computeGraphData(metrics, deployment_time);
-        const { hasMetrics, memoryMetrics, deploymentTime } = vm;
+        const { hasMetrics, memoryMetrics, deploymentTime, memoryFrom, memoryTo } = vm;
 
         expect(hasMetrics).toBeTruthy();
         expect(memoryMetrics.length > 0).toBeTruthy();
         expect(deploymentTime).toEqual(deployment_time);
+        expect(memoryFrom).toEqual('9.13');
+        expect(memoryTo).toEqual('4.28');
       });
     });