Merge branch 'winh-countdown-component' into 'master'

Add reusable component for counting down

See merge request gitlab-org/gitlab-ce!22499

2 files changed, 61 insertions, 0 deletions

diff --git a/app/assets/javascripts/lib/utils/datetime_utility.js b/app/assets/javascripts/lib/utils/datetime_utility.js
index 1bdf98d0c97..46740308f17 100644
--- a/app/assets/javascripts/lib/utils/datetime_utility.js
+++ b/app/assets/javascripts/lib/utils/datetime_utility.js
@@ -473,3 +473,15 @@ export const stringifyTime = timeObject => {
  */
 export const abbreviateTime = timeStr =>
   timeStr.split(' ').filter(unitStr => unitStr.charAt(0) !== '0')[0];
+
+/**
+ * Calculates the milliseconds between now and a given date string.
+ * The result cannot become negative.
+ *
+ * @param endDate date string that the time difference is calculated for
+ * @return {number} number of milliseconds remaining until the given date
+ */
+export const calculateRemainingMilliseconds = endDate => {
+  const remainingMilliseconds = new Date(endDate).getTime() - Date.now();
+  return Math.max(remainingMilliseconds, 0);
+};
diff --git a/app/assets/javascripts/vue_shared/components/gl_countdown.vue b/app/assets/javascripts/vue_shared/components/gl_countdown.vue
new file mode 100644
index 00000000000..9327a2a4a6c
--- /dev/null
+++ b/app/assets/javascripts/vue_shared/components/gl_countdown.vue
@@ -0,0 +1,49 @@
+<script>
+import { calculateRemainingMilliseconds, formatTime } from '~/lib/utils/datetime_utility';
+
+/**
+ * Counts down to a given end date.
+ */
+export default {
+  props: {
+    endDateString: {
+      type: String,
+      required: true,
+      validator(value) {
+        return !Number.isNaN(new Date(value).getTime());
+      },
+    },
+  },
+
+  data() {
+    return {
+      remainingTime: formatTime(0),
+      countdownUpdateIntervalId: null,
+    };
+  },
+
+  mounted() {
+    const updateRemainingTime = () => {
+      const remainingMilliseconds = calculateRemainingMilliseconds(this.endDateString);
+      this.remainingTime = formatTime(remainingMilliseconds);
+    };
+
+    updateRemainingTime();
+    this.countdownUpdateIntervalId = window.setInterval(updateRemainingTime, 1000);
+  },
+
+  beforeDestroy() {
+    window.clearInterval(this.countdownUpdateIntervalId);
+  },
+};
+</script>
+
+<template>
+  <time
+    v-gl-tooltip
+    :datetime="endDateString"
+    :title="endDateString"
+  >
+    {{ remainingTime }}
+  </time>
+</template>