Merge pull request #68 from quickwit-oss/ddelemeny/field-caps-timestamps

Limit field_caps request to time range, fixes #61

Author: fmassot

src/datasource.ts

@@ -384,9 +384,11 @@ export class QuickwitDataSource
     );
   }
 
-  getFields(spec: FieldCapsSpec={}): Observable<MetricFindValue[]> {
-    // TODO: use the time range.
-    return from(this.getResource('_elastic/' + this.index + '/_field_caps')).pipe(
+  getFields(spec: FieldCapsSpec={}, range = getDefaultTimeRange()): Observable<MetricFindValue[]> {
+    return from(this.getResource('_elastic/' + this.index + '/_field_caps', {
+      start_timestamp: Math.floor(range.from.valueOf()/SECOND),
+      end_timestamp: Math.ceil(range.to.valueOf()/SECOND),
+    })).pipe(
       map((field_capabilities_response: FieldCapabilitiesResponse) => {
         const shouldAddField = (field: any) => {
           if (spec.aggregatable !== undefined && field.aggregatable !== spec.aggregatable) {