tech: migrating elasticsearch to typescript

public/app/plugins/datasource/elasticsearch/index_pattern.ts

@@ -0,0 +1,43 @@
+///<reference path="../../../headers/common.d.ts" />
+
+import moment from 'moment';
+
+const intervalMap = {
+  "Hourly":  { startOf: 'hour',     amount: 'hours'},
+  "Daily":   { startOf: 'day',      amount: 'days'},
+  "Weekly":  { startOf: 'isoWeek',  amount: 'weeks'},
+  "Monthly": { startOf: 'month',    amount: 'months'},
+  "Yearly":  { startOf: 'year',     amount: 'years'},
+};
+
+export class IndexPattern {
+
+  constructor(private pattern, private interval: string | null) { }
+
+  getIndexForToday() {
+    if (this.interval) {
+      return moment.utc().format(this.pattern);
+    } else {
+      return this.pattern;
+    }
+  };
+
+  getIndexList(from, to) {
+    if (!this.interval) {
+      return this.pattern;
+    }
+
+    var intervalInfo = intervalMap[this.interval];
+    var start = moment(from).utc().startOf(intervalInfo.startOf);
+    var end = moment(to).utc().startOf(intervalInfo.startOf).valueOf();
+    var indexList = [];
+
+    while (start <= end) {
+      indexList.push(start.format(this.pattern));
+      start.add(1, intervalInfo.amount);
+    }
+
+    return indexList;
+  }
+}
+