address comments

Author: limotova

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToStringFromAggregateMetricDoubleEvaluator.java

@@ -43,24 +43,10 @@ public Block evalBlock(Block b) {
         int positionCount = block.getPositionCount();
         try (BytesRefBlock.Builder builder = driverContext.blockFactory().newBytesRefBlockBuilder(positionCount)) {
             for (int p = 0; p < positionCount; p++) {
-                int valueCount = block.getValueCount(p);
-                int start = block.getFirstValueIndex(p);
-                int end = start + valueCount;
-                boolean positionOpened = false;
-                boolean valuesAppended = false;
-                for (int i = start; i < end; i++) {
-                    BytesRef value = evalValue(block, i);
-                    if (positionOpened == false && valueCount > 1) {
-                        builder.beginPositionEntry();
-                        positionOpened = true;
-                    }
-                    builder.appendBytesRef(value);
-                    valuesAppended = true;
-                }
-                if (valuesAppended == false) {
+                if (block.isNull(p)) {
                     builder.appendNull();
-                } else if (positionOpened) {
-                    builder.endPositionEntry();
+                } else {
+                    builder.appendBytesRef(evalValue(block, p));
                 }
             }
             return builder.build();

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/type/EsqlDataTypeConverter.java

@@ -8,6 +8,7 @@
 package org.elasticsearch.xpack.esql.type;
 
 import org.apache.lucene.util.BytesRef;
+import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.logging.LoggerMessageFormat;
@@ -16,10 +17,14 @@
 import org.elasticsearch.common.time.DateFormatters;
 import org.elasticsearch.common.time.DateUtils;
 import org.elasticsearch.compute.data.AggregateMetricDoubleBlockBuilder;
+import org.elasticsearch.compute.data.AggregateMetricDoubleBlockBuilder.Metric;
 import org.elasticsearch.compute.data.CompositeBlock;
 import org.elasticsearch.compute.data.DoubleBlock;
 import org.elasticsearch.compute.data.IntBlock;
 import org.elasticsearch.search.DocValueFormat;
+import org.elasticsearch.xcontent.XContentBuilder;
+import org.elasticsearch.xcontent.json.JsonXContent;
+import org.elasticsearch.xpack.esql.EsqlIllegalArgumentException;
 import org.elasticsearch.xpack.esql.core.InvalidArgumentException;
 import org.elasticsearch.xpack.esql.core.QlIllegalArgumentException;
 import org.elasticsearch.xpack.esql.core.expression.Expression;
@@ -62,7 +67,6 @@
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
-import java.util.StringJoiner;
 import java.util.function.BiFunction;
 import java.util.function.Function;
 
@@ -670,24 +674,23 @@ public static long booleanToUnsignedLong(boolean number) {
     }
 
     public static String aggregateMetricDoubleBlockToString(CompositeBlock compositeBlock, int index) {
-        var minBlock = compositeBlock.getBlock(AggregateMetricDoubleBlockBuilder.Metric.MIN.getIndex());
-        var maxBlock = compositeBlock.getBlock(AggregateMetricDoubleBlockBuilder.Metric.MAX.getIndex());
-        var sumBlock = compositeBlock.getBlock(AggregateMetricDoubleBlockBuilder.Metric.SUM.getIndex());
-        var countBlock = compositeBlock.getBlock(AggregateMetricDoubleBlockBuilder.Metric.COUNT.getIndex());
-        final StringJoiner joiner = new StringJoiner(", ");
-        if (maxBlock.isNull(index) == false) {
-            joiner.add("\"max\": " + ((DoubleBlock) maxBlock).getDouble(index));
-        }
-        if (minBlock.isNull(index) == false) {
-            joiner.add("\"min\": " + ((DoubleBlock) minBlock).getDouble(index));
-        }
-        if (sumBlock.isNull(index) == false) {
-            joiner.add("\"sum\": " + ((DoubleBlock) sumBlock).getDouble(index));
-        }
-        if (countBlock.isNull(index) == false) {
-            joiner.add("\"value_count\": " + ((IntBlock) countBlock).getInt(index));
+        try (XContentBuilder builder = JsonXContent.contentBuilder()) {
+            builder.startObject();
+            for (Metric metric : List.of(Metric.MIN, Metric.MAX, Metric.SUM)) {
+                var block = compositeBlock.getBlock(metric.getIndex());
+                if (block.isNull(index) == false) {
+                    builder.field(metric.name().toLowerCase(), ((DoubleBlock) block).getDouble(index));
+                }
+            }
+            var countBlock = compositeBlock.getBlock(AggregateMetricDoubleBlockBuilder.Metric.COUNT.getIndex());
+            if (countBlock.isNull(index) == false) {
+                builder.field("value_count", ((IntBlock) countBlock).getInt(index));
+            }
+            builder.endObject();
+            return Strings.toString(builder);
+        } catch (IOException e) {
+            throw new EsqlIllegalArgumentException("error rendering aggregate metric double", e);
         }
-        return "{ " + joiner + " }";
     }
 
     public enum EsqlConverter implements Converter {

x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/40_tsdb.yml

@@ -141,6 +141,8 @@ setup:
           - '{"@timestamp": "2021-04-28T19:50:24.467Z", "agg_metric": {"max": 10, "min": 3}, "k8s": {"pod": {"uid":"947e4ced-1786-4e53-9e0c-5c447e959507"}}}'
           - '{"index": {}}'
           - '{"@timestamp": "2021-04-28T19:50:44.467Z", "agg_metric": {"max": 17, "min": 2}, "k8s": {"pod": {"uid":"df3145b3-0563-4d3b-a0f7-897eb2876ea9"}}}'
+          - '{"index": {}}'
+          - '{"@timestamp": "2021-04-28T19:51:04.467Z", "k8s": {"pod": {"uid":"df3145b3-0563-4d3b-a0f7-897eb2876ea9"}}}'
 
   - do:
       indices.create:
@@ -466,7 +468,32 @@ render aggregate_metric_double when missing min and max:
   - length: {values.0: 1}
   - match: {columns.0.name: "agg_metric"}
   - match: {columns.0.type: "aggregate_metric_double"}
-  - match: {values.0.0: '{ "sum": 1.0, "value_count": 10 }'}
+  - match: {values.0.0: '{"sum":1.0,"value_count":10}'}
+
+
+---
+render aggregate_metric_double when missing value:
+  - requires:
+      test_runner_features: [ capabilities ]
+      capabilities:
+        - method: POST
+          path: /_query
+          parameters: [ ]
+          capabilities: [ aggregate_metric_double_rendering ]
+      reason: "Support for rendering aggregate_metric_doubles"
+  - do:
+      allowed_warnings_regex:
+        - "No limit defined, adding default limit of \\[.*\\]"
+      esql.query:
+        body:
+          query: 'FROM test3 | WHERE @timestamp == "2021-04-28T19:51:04.467Z" | KEEP agg_metric'
+
+  - length: {values: 1}
+  - length: {values.0: 1}
+  - match: {columns.0.name: "agg_metric"}
+  - match: {columns.0.type: "aggregate_metric_double"}
+  - match: {values.0.0: null}
+
 
 ---
 to_string aggregate_metric_double:
@@ -489,7 +516,7 @@ to_string aggregate_metric_double:
   - length: {values.0: 1}
   - match: {columns.0.name: "agg"}
   - match: {columns.0.type: "keyword"}
-  - match: {values.0.0: '{ "sum": 1.0, "value_count": 10 }'}
+  - match: {values.0.0: '{"sum":1.0,"value_count":10}'}
 
 ---
 from index pattern unsupported counter:
@@ -526,7 +553,7 @@ from index pattern unsupported counter:
   - match: {columns.7.type: "keyword"}
   - match: {columns.8.name: "metricset"}
   - match: {columns.8.type: "keyword"}
-  - length: {values: 15}
+  - length: {values: 16}
 
 ---
 from index pattern explicit counter use:
@@ -547,7 +574,7 @@ from index pattern explicit counter use:
           query: 'FROM test* | keep *.tx'
   - match: {columns.0.name: "k8s.pod.network.tx"}
   - match: {columns.0.type: "unsupported"}
-  - length: {values: 15}
+  - length: {values: 16}
 
 ---
 _source:

x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/40_unsupported_types.yml

@@ -190,7 +190,7 @@ unsupported:
   - match: { columns.28.type: integer }
 
   - length: { values: 1 }
-  - match: { values.0.0: '{ "max": 3.0, "min": 1.0, "sum": 10.1, "value_count": 5 }' }
+  - match: { values.0.0: '{"min":1.0,"max":3.0,"sum":10.1,"value_count":5}' }
   - match: { values.0.1: null }
   - match: { values.0.2: null }
   - match: { values.0.3: "2015-01-01T12:10:30.123456789Z" }

x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/46_downsample.yml

@@ -117,3 +117,32 @@ setup:
   - match: {values.0.2: 5332018.0}
   - match: {values.0.3: 8}
 
+---
+"Render stats from downsampled index":
+  - requires:
+      test_runner_features: [capabilities]
+      capabilities:
+        - method: POST
+          path: /_query
+          parameters: []
+          capabilities: [aggregate_metric_double_rendering]
+      reason: "Support for rendering aggregate_metric_doubles"
+  - do:
+      indices.downsample:
+        index: test
+        target_index: test-downsample
+        body: >
+          {
+            "fixed_interval": "1h"
+          }
+  - is_true: acknowledged
+
+  - do:
+      esql.query:
+        body:
+          query: "FROM test-downsample | WHERE @timestamp == \"2021-04-28T19:00:00.000Z\" | KEEP k8s.pod.network.rx | LIMIT 100"
+  - length: {values: 1}
+  - length: {values.0: 1}
+  - match: {columns.0.name: "k8s.pod.network.rx"}
+  - match: {columns.0.type: "aggregate_metric_double"}
+  - match: {values.0.0: '{"min":530604.0,"max":530605.0,"sum":1061209.0,"value_count":2}'}