Elasticsearch: Refactor parse query (#60440)

* Refactor parse query to functions

* Move parsing to new file

* Create empty result variable and use it when returning early

* Fix linting

* Revert "Create empty result variable and use it when returning early"

This reverts commit 36a503f66e52f8213c673972774329a963a78100.

pkg/tsdb/elasticsearch/parse_query.go

@@ -0,0 +1,110 @@
+package elasticsearch
+
+import (
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	"github.com/grafana/grafana/pkg/components/simplejson"
+)
+
+func parseQuery(tsdbQuery []backend.DataQuery) ([]*Query, error) {
+	queries := make([]*Query, 0)
+	for _, q := range tsdbQuery {
+		model, err := simplejson.NewJson(q.JSON)
+		if err != nil {
+			return nil, err
+		}
+		timeField, err := model.Get("timeField").String()
+		if err != nil {
+			return nil, err
+		}
+		rawQuery := model.Get("query").MustString()
+		bucketAggs, err := parseBucketAggs(model)
+		if err != nil {
+			return nil, err
+		}
+		metrics, err := parseMetrics(model)
+		if err != nil {
+			return nil, err
+		}
+		alias := model.Get("alias").MustString("")
+		interval := model.Get("interval").MustString("")
+
+		queries = append(queries, &Query{
+			TimeField:     timeField,
+			RawQuery:      rawQuery,
+			BucketAggs:    bucketAggs,
+			Metrics:       metrics,
+			Alias:         alias,
+			Interval:      interval,
+			RefID:         q.RefID,
+			MaxDataPoints: q.MaxDataPoints,
+		})
+	}
+
+	return queries, nil
+}
+
+func parseBucketAggs(model *simplejson.Json) ([]*BucketAgg, error) {
+	var err error
+	var result []*BucketAgg
+	for _, t := range model.Get("bucketAggs").MustArray() {
+		aggJSON := simplejson.NewFromAny(t)
+		agg := &BucketAgg{}
+
+		agg.Type, err = aggJSON.Get("type").String()
+		if err != nil {
+			return nil, err
+		}
+
+		agg.ID, err = aggJSON.Get("id").String()
+		if err != nil {
+			return nil, err
+		}
+
+		agg.Field = aggJSON.Get("field").MustString()
+		agg.Settings = simplejson.NewFromAny(aggJSON.Get("settings").MustMap())
+
+		result = append(result, agg)
+	}
+	return result, nil
+}
+
+func parseMetrics(model *simplejson.Json) ([]*MetricAgg, error) {
+	var err error
+	var result []*MetricAgg
+	for _, t := range model.Get("metrics").MustArray() {
+		metricJSON := simplejson.NewFromAny(t)
+		metric := &MetricAgg{}
+
+		metric.Field = metricJSON.Get("field").MustString()
+		metric.Hide = metricJSON.Get("hide").MustBool(false)
+		metric.ID = metricJSON.Get("id").MustString()
+		metric.PipelineAggregate = metricJSON.Get("pipelineAgg").MustString()
+		// In legacy editors, we were storing empty settings values as "null"
+		// The new editor doesn't store empty strings at all
+		// We need to ensures backward compatibility with old queries and remove empty fields
+		settings := metricJSON.Get("settings").MustMap()
+		for k, v := range settings {
+			if v == "null" {
+				delete(settings, k)
+			}
+		}
+		metric.Settings = simplejson.NewFromAny(settings)
+		metric.Meta = simplejson.NewFromAny(metricJSON.Get("meta").MustMap())
+		metric.Type, err = metricJSON.Get("type").String()
+		if err != nil {
+			return nil, err
+		}
+
+		if isPipelineAggWithMultipleBucketPaths(metric.Type) {
+			metric.PipelineVariables = map[string]string{}
+			pvArr := metricJSON.Get("pipelineVariables").MustArray()
+			for _, v := range pvArr {
+				kv := v.(map[string]interface{})
+				metric.PipelineVariables[kv["name"].(string)] = kv["pipelineAgg"].(string)
+			}
+		}
+
+		result = append(result, metric)
+	}
+	return result, nil
+}