Rather than looping data ourselves, d3 loops it

app/assets/javascripts/monitoring/deployments.js

@@ -4,12 +4,13 @@ export default class Deployments {
   constructor(width, height) {
     this.width = width;
     this.height = height;
+    this.data = [];
     this.dateFormat = d3.time.format('%b %d, %Y');
     this.timeFormat = d3.time.format('%H:%M%p');
 
     this.endpoint = document.getElementById('js-metrics').dataset.deploymentEndpoint;
 
-    Deployments.createGradientDef();
+    this.createGradientDef();
   }
 
   init(chartData) {
@@ -29,15 +30,12 @@ export default class Deployments {
       dataType: 'JSON',
     })
     .done((data) => {
-      this.data = [];
-
       data.deployments.forEach((deployment) => {
-        const minInSeconds = 1000 * 60;
-        let time = new Date(deployment.created_at);
-        time = new Date(Math.round(time.getTime() / minInSeconds) * minInSeconds);
-        time.setSeconds(this.chartData[0].time.getSeconds());
+        const time = new Date(deployment.created_at);
         const xPos = Math.floor(this.x(time));
 
+        time.setSeconds(this.chartData[0].time.getSeconds());
+
         if (xPos >= 0) {
           this.data.push({
             id: deployment.id,
@@ -65,7 +63,7 @@ export default class Deployments {
     });
   }
 
-  static createGradientDef() {
+  createGradientDef() {
     const defs = d3.select('body')
       .append('svg')
       .attr({
@@ -84,9 +82,7 @@ export default class Deployments {
         'stop-color': '#000',
         'stop-opacity': 0.4,
       })
-      .select(function selectParentNode() {
-        return this.parentNode;
-      })
+      .select(this.selectParentNode)
       .append('stop')
       .attr({
         offset: '100%',
@@ -116,9 +112,7 @@ export default class Deployments {
         width: 3,
         fill: 'url(#shadow-gradient)',
       })
-      .select(function selectParentNode() {
-        return this.parentNode;
-      })
+      .select(this.selectParentNode)
       .append('line')
       .attr({
         class: 'deployment-line',
@@ -130,60 +124,52 @@ export default class Deployments {
   }
 
   createDeployInfoBox(chart, key) {
-    this.data.forEach((d) => {
-      const group = chart.select(`.deploy-info-${d.id}-${key}`)
+    chart.selectAll('.deploy-info')
+      .selectAll('.js-deploy-info-box')
+      .data(this.data)
+      .enter()
+      .select(d => document.querySelector(`.deploy-info-${d.id}-${key}`))
       .append('svg')
       .attr({
+        class: 'js-deploy-info-box hidden',
         x: 3,
         y: 0,
+        width: 92,
         height: 60,
-        });
-
-      const rect = group.append('rect')
+      })
+      .append('rect')
       .attr({
         class: 'rect-text-metric deploy-info-rect rect-metric',
         x: 1,
         y: 1,
         rx: 2,
-          height: group.attr('height') - 2,
-        });
-
-      const textGroup = group.append('g')
+        width: 90,
+        height: 58,
+      })
+      .select(this.selectParentNode)
+      .append('g')
       .attr({
         transform: 'translate(5, 2)',
-        });
-
-      textGroup.append('text')
+      })
+      .append('text')
       .attr({
         class: 'deploy-info-text text-metric-bold',
       })
-        .text(() => {
-          const isTag = d.tag;
-          const refText = isTag ? d.ref : d.sha.slice(0, 6);
-
-          return refText;
-        });
-
-      textGroup.append('text')
+      .text(Deployments.refText)
+      .select(this.selectParentNode)
+      .append('text')
       .attr({
         class: 'deploy-info-text',
         y: 18,
       })
-        .text(() => this.dateFormat(d.time));
-
-      textGroup.append('text')
+      .text(d => this.dateFormat(d.time))
+      .select(this.selectParentNode)
+      .append('text')
       .attr({
         class: 'deploy-info-text text-metric-bold',
         y: 38,
       })
-        .text(() => this.timeFormat(d.time));
-
-      group.attr('width', Math.floor(textGroup.node().getBoundingClientRect().width) + 14);
-
-      rect.attr('width', Math.floor(textGroup.node().getBoundingClientRect().width) + 10);
-
-      group.attr('class', 'js-deploy-info-box hidden');
-    });
+      .text(d => this.timeFormat(d.time));
   }
 
   static toggleDeployTextbox(deploy, key, showInfoBox) {
@@ -208,4 +194,16 @@ export default class Deployments {
 
     return dataFound;
   }
+
+  /* `this` is bound to the D3 node */
+  selectParentNode() {
+    return this.parentNode;
+  }
+
+  static refText(d) {
+    const isTag = d.tag;
+    const refText = isTag ? d.ref : d.sha.slice(0, 6);
+
+    return refText;
+  }
 }

spec/javascripts/monitoring/deployments_spec.js

@@ -110,4 +110,24 @@ describe('Metrics deployments', () => {
       graphElement().querySelector('.deploy-info-1-cpu_values .js-deploy-info-box.hidden'),
     ).not.toBeNull();
   });
+
+  describe('refText', () => {
+    it('returns shortened SHA', () => {
+      expect(
+        Deployments.refText({
+          tag: false,
+          sha: '123456789',
+        }),
+      ).toBe('123456');
+    });
+
+    it('returns tag name', () => {
+      expect(
+        Deployments.refText({
+          tag: true,
+          ref: 'v1.0',
+        }),
+      ).toBe('v1.0');
+    });
+  });
 });