Resolve "Hover and legend data should be linked"

app/assets/javascripts/monitoring/components/dashboard.vue

@@ -29,6 +29,7 @@
         showEmptyState: true,
         updateAspectRatio: false,
         updatedAspectRatios: 0,
+        hoverData: {},
         resizeThrottled: {},
       };
     },
@@ -64,6 +65,10 @@
           this.updatedAspectRatios = 0;
         }
       },
+
+      hoverChanged(data) {
+        this.hoverData = data;
+      },
     },
     created() {
@@ -72,10 +77,12 @@
         deploymentEndpoint: this.deploymentEndpoint,
       });
       eventHub.$on('toggleAspectRatio', this.toggleAspectRatio);
+      eventHub.$on('hoverChanged', this.hoverChanged);
     },
     beforeDestroy() {
       eventHub.$off('toggleAspectRatio', this.toggleAspectRatio);
+      eventHub.$off('hoverChanged', this.hoverChanged);
       window.removeEventListener('resize', this.resizeThrottled, false);
     },
@@ -102,6 +109,7 @@
         v-for="(graphData, index) in groupData.metrics"
         :key="index"
         :graph-data="graphData"
+        :hover-data="hoverData"
         :update-aspect-ratio="updateAspectRatio"
         :deployment-data="store.deploymentData"
       />

app/assets/javascripts/monitoring/components/graph.vue

@@ -7,12 +7,10 @@
   import MonitoringMixin from '../mixins/monitoring_mixins';
   import eventHub from '../event_hub';
   import measurements from '../utils/measurements';
-  import { timeScaleFormat } from '../utils/date_time_formatters';
+  import { timeScaleFormat, bisectDate } from '../utils/date_time_formatters';
   import createTimeSeries from '../utils/multiple_time_series';
   import bp from '../../breakpoints';
-  const bisectDate = d3.bisector(d => d.time).left;
-
   export default {
     props: {
       graphData: {
@@ -27,6 +25,11 @@
         type: Array,
         required: true,
       },
+      hoverData: {
+        type: Object,
+        required: false,
+        default: () => ({}),
+      },
     },
     mixins: [MonitoringMixin],
@@ -52,6 +55,7 @@
         currentXCoordinate: 0,
         currentFlagPosition: 0,
         showFlag: false,
+        showFlagContent: false,
         showDeployInfo: true,
         timeSeries: [],
       };
@@ -122,22 +126,14 @@
         const d1 = firstTimeSeries.values[overlayIndex];
         if (d0 === undefined || d1 === undefined) return;
         const evalTime = timeValueOverlay - d0[0] > d1[0] - timeValueOverlay;
-        this.currentData = evalTime ? d1 : d0;
-        this.currentDataIndex = evalTime ? overlayIndex : (overlayIndex - 1);
-        this.currentXCoordinate = Math.floor(firstTimeSeries.timeSeriesScaleX(this.currentData.time));
+        const hoveredDataIndex = evalTime ? overlayIndex : (overlayIndex - 1);
+        const hoveredDate = firstTimeSeries.values[hoveredDataIndex].time;
         const currentDeployXPos = this.mouseOverDeployInfo(point.x);
-        if (this.currentXCoordinate > (this.graphWidth - 200)) {
-          this.currentFlagPosition = this.currentXCoordinate - 103;
-        } else {
-          this.currentFlagPosition = this.currentXCoordinate;
-        }
-
-        if (currentDeployXPos) {
-          this.showFlag = false;
-        } else {
-          this.showFlag = true;
-        }
+        eventHub.$emit('hoverChanged', {
+          hoveredDate,
+          currentDeployXPos,
+        });
       },
       renderAxesPaths() {
@@ -194,6 +190,10 @@
           eventHub.$emit('toggleAspectRatio');
         }
       },
+
+      hoverData() {
+        this.positionFlag();
+      },
     },
     mounted() {
@@ -203,7 +203,10 @@
 </script>
 <template>
-  <div class="prometheus-graph">
+  <div 
+    class="prometheus-graph"
+    @mouseover="showFlagContent = true"
+    @mouseleave="showFlagContent = false">
     <h5 class="text-center graph-title">
       {{graphData.title}}
     </h5>
@@ -257,6 +260,7 @@
               :current-flag-position="currentFlagPosition"
               :graph-height="graphHeight"
               :graph-height-offset="graphHeightOffset"
+              :show-flag-content="showFlagContent"
             />
             <rect
               class="prometheus-graph-overlay"

app/assets/javascripts/monitoring/components/graph/flag.vue

@@ -23,6 +23,10 @@
         type: Number,
         required: true,
       },
+      showFlagContent: {
+        type: Boolean,
+        required: true,
+      },
     },
     data() {
@@ -57,6 +61,7 @@
       transform="translate(-5, 20)">
     </line>
     <svg 
+      v-if="showFlagContent"
       class="rect-text-metric"
       :x="currentFlagPosition"
       y="0">

app/assets/javascripts/monitoring/mixins/monitoring_mixins.js

+import { bisectDate } from '../utils/date_time_formatters';
+
 const mixins = {
   methods: {
     mouseOverDeployInfo(mouseXPos) {
@@ -18,6 +20,7 @@ const mixins = {
       return dataFound;
     },
+
     formatDeployments() {
       this.reducedDeploymentData = this.deploymentData.reduce((deploymentDataArray, deployment) => {
         const time = new Date(deployment.created_at);
@@ -40,6 +43,25 @@ const mixins = {
         return deploymentDataArray;
       }, []);
     },
+
+    positionFlag() {
+      const timeSeries = this.timeSeries[0];
+      const hoveredDataIndex = bisectDate(timeSeries.values, this.hoverData.hoveredDate, 1);
+      this.currentData = timeSeries.values[hoveredDataIndex];
+      this.currentDataIndex = hoveredDataIndex;
+      this.currentXCoordinate = Math.floor(timeSeries.timeSeriesScaleX(this.currentData.time));
+      if (this.currentXCoordinate > (this.graphWidth - 200)) {
+        this.currentFlagPosition = this.currentXCoordinate - 103;
+      } else {
+        this.currentFlagPosition = this.currentXCoordinate;
+      }
+
+      if (this.hoverData.currentDeployXPos) {
+        this.showFlag = false;
+      } else {
+        this.showFlag = true;
+      }
+    },
   },
 };

app/assets/javascripts/monitoring/utils/date_time_formatters.js

@@ -2,6 +2,7 @@ import d3 from 'd3';
 export const dateFormat = d3.time.format('%b %-d, %Y');
 export const timeFormat = d3.time.format('%-I:%M%p');
+export const bisectDate = d3.bisector(d => d.time).left;
 export const timeScaleFormat = d3.time.format.multi([
   ['.%L', d => d.getMilliseconds()],

changelogs/unreleased/38036-hover-and-legend-data-should-be-linked.yml

+---
+title: Sync up hover and legend data across all graphs for the prometheus dashboard
+merge_request:
+author:
+type: fixed

spec/javascripts/monitoring/graph/flag_spec.js

@@ -14,19 +14,22 @@ function getCoordinate(component, selector, coordinate) {
   return parseInt(coordinateVal, 10);
 }
+const defaultValuesComponent = {
+  currentXCoordinate: 200,
+  currentYCoordinate: 100,
+  currentFlagPosition: 100,
+  currentData: {
+    time: new Date('2017-06-04T18:17:33.501Z'),
+    value: '1.49609375',
+  },
+  graphHeight: 300,
+  graphHeightOffset: 120,
+  showFlagContent: true,
+};
+
 describe('GraphFlag', () => {
   it('has a line and a circle located at the currentXCoordinate and currentYCoordinate', () => {
-    const component = createComponent({
-      currentXCoordinate: 200,
-      currentYCoordinate: 100,
-      currentFlagPosition: 100,
-      currentData: {
-        time: new Date('2017-06-04T18:17:33.501Z'),
-        value: '1.49609375',
-      },
-      graphHeight: 300,
-      graphHeightOffset: 120,
-    });
+    const component = createComponent(defaultValuesComponent);
     expect(getCoordinate(component, '.selected-metric-line', 'x1'))
       .toEqual(component.currentXCoordinate);
@@ -35,17 +38,7 @@ describe('GraphFlag', () => {
   });
   it('has a SVG with the class rect-text-metric at the currentFlagPosition', () => {
-    const component = createComponent({
-      currentXCoordinate: 200,
-      currentYCoordinate: 100,
-      currentFlagPosition: 100,
-      currentData: {
-        time: new Date('2017-06-04T18:17:33.501Z'),
-        value: '1.49609375',
-      },
-      graphHeight: 300,
-      graphHeightOffset: 120,
-    });
+    const component = createComponent(defaultValuesComponent);
     const svg = component.$el.querySelector('.rect-text-metric');
     expect(svg.tagName).toEqual('svg');
@@ -54,17 +47,7 @@ describe('GraphFlag', () => {
   describe('Computed props', () => {
     it('calculatedHeight', () => {
-      const component = createComponent({
-        currentXCoordinate: 200,
-        currentYCoordinate: 100,
-        currentFlagPosition: 100,
-        currentData: {
-          time: new Date('2017-06-04T18:17:33.501Z'),
-          value: '1.49609375',
-        },
-        graphHeight: 300,
-        graphHeightOffset: 120,
-      });
+      const component = createComponent(defaultValuesComponent);
       expect(component.calculatedHeight).toEqual(180);
     });

spec/javascripts/monitoring/graph_spec.js

@@ -86,4 +86,22 @@ describe('Graph', () => {
     expect(component.yAxisLabel).toEqual(component.graphData.y_label);
     expect(component.legendTitle).toEqual(component.graphData.queries[0].label);
   });
+
+  it('sets the currentData object based on the hovered data index', () => {
+    const component = createComponent({
+      graphData: convertedMetrics[1],
+      classType: 'col-md-6',
+      updateAspectRatio: false,
+      deploymentData,
+      graphIdentifier: 0,
+      hoverData: {
+        hoveredDate: new Date('Sun Aug 27 2017 06:11:51 GMT-0500 (CDT)'),
+        currentDeployXPos: null,
+      },
+    });
+
+    component.positionFlag();
+    expect(component.currentData).toBe(component.timeSeries[0].values[10]);
+    expect(component.currentDataIndex).toEqual(10);
+  });
 });