[Metrics UI] Replace date_histogram with date_range aggregation in threshold alert (#100004)

* [Metrics UI] Replace date_histogram with date_range aggregation in threshold alert

* Remove console.log

* Fix rate aggregation and offset

x-pack/plugins/infra/server/lib/alerting/metric_threshold/lib/evaluate_alert.ts

@@ -25,6 +25,7 @@ interface Aggregation {
     buckets: Array<{
       aggregatedValue: { value: number; values?: Array<{ key: number; value: number }> };
       doc_count: number;
+      to_as_string: string;
       key_as_string: string;
     }>;
   };
@@ -60,6 +61,7 @@ export const evaluateAlert = <Params extends EvaluatedAlertParams = EvaluatedAle
         filterQuery,
         timeframe
       );
+
       const { threshold, warningThreshold, comparator, warningComparator } = criterion;
       const pointsEvaluator = (points: any[] | typeof NaN | null, t?: number[], c?: Comparator) => {
         if (!t || !c) return [false];
@@ -179,18 +181,21 @@ const getValuesFromAggregations = (
     const { buckets } = aggregations.aggregatedIntervals;
     if (!buckets.length) return null; // No Data state
     if (aggType === Aggregators.COUNT) {
-      return buckets.map((bucket) => ({ key: bucket.key_as_string, value: bucket.doc_count }));
+      return buckets.map((bucket) => ({
+        key: bucket.to_as_string,
+        value: bucket.doc_count,
+      }));
     }
     if (aggType === Aggregators.P95 || aggType === Aggregators.P99) {
       return buckets.map((bucket) => {
         const values = bucket.aggregatedValue?.values || [];
         const firstValue = first(values);
         if (!firstValue) return null;
-        return { key: bucket.key_as_string, value: firstValue.value };
+        return { key: bucket.to_as_string, value: firstValue.value };
       });
     }
     return buckets.map((bucket) => ({
-      key: bucket.key_as_string,
+      key: bucket.key_as_string ?? bucket.to_as_string,
       value: bucket.aggregatedValue?.value ?? null,
     }));
   } catch (e) {

x-pack/plugins/infra/server/lib/alerting/metric_threshold/lib/metric_query.ts

@@ -37,11 +37,12 @@ export const getElasticsearchMetricQuery = (
   }
   const interval = `${timeSize}${timeUnit}`;
   const intervalAsSeconds = getIntervalInSeconds(interval);
+  const intervalAsMS = intervalAsSeconds * 1000;
 
   const to = roundTimestamp(timeframe ? timeframe.end : Date.now(), timeUnit);
   // We need enough data for 5 buckets worth of data. We also need
   // to convert the intervalAsSeconds to milliseconds.
-  const minimumFrom = to - intervalAsSeconds * 1000 * MINIMUM_BUCKETS;
+  const minimumFrom = to - intervalAsMS * MINIMUM_BUCKETS;
 
   const from = roundTimestamp(
     timeframe && timeframe.start <= minimumFrom ? timeframe.start : minimumFrom,
@@ -49,6 +50,7 @@ export const getElasticsearchMetricQuery = (
   );
 
   const offset = calculateDateHistogramOffset({ from, to, interval, field: timefield });
+  const offsetInMS = parseInt(offset, 10) * 1000;
 
   const aggregations =
     aggType === Aggregators.COUNT
@@ -65,20 +67,34 @@ export const getElasticsearchMetricQuery = (
           },
         };
 
-  const baseAggs = {
-    aggregatedIntervals: {
-      date_histogram: {
-        field: timefield,
-        fixed_interval: interval,
-        offset,
-        extended_bounds: {
-          min: from,
-          max: to,
-        },
-      },
-      aggregations,
-    },
-  };
+  const baseAggs =
+    aggType === Aggregators.RATE
+      ? {
+          aggregatedIntervals: {
+            date_histogram: {
+              field: timefield,
+              fixed_interval: interval,
+              offset,
+              extended_bounds: {
+                min: from,
+                max: to,
+              },
+            },
+            aggregations,
+          },
+        }
+      : {
+          aggregatedIntervals: {
+            date_range: {
+              field: timefield,
+              ranges: Array.from(Array(Math.floor((to - from) / intervalAsMS)), (_, i) => ({
+                from: from + intervalAsMS * i + offsetInMS,
+                to: from + intervalAsMS * (i + 1) + offsetInMS,
+              })),
+            },
+            aggregations,
+          },
+        };
 
   const aggs = groupBy
     ? {

x-pack/plugins/infra/server/lib/alerting/metric_threshold/test_mocks.ts

@@ -13,7 +13,7 @@ const bucketsA = [
   {
     doc_count: 3,
     aggregatedValue: { value: 1.0, values: [{ key: 95.0, value: 1.0 }] },
-    key_as_string: new Date(1577858400000).toISOString(),
+    to_as_string: new Date(1577858400000).toISOString(),
   },
 ];