Download CSV: format the dates (#24992)

* export formatted dates

* remove if(true)

* display processor

packages/grafana-data/src/vector/FormattedVector.ts

@@ -0,0 +1,25 @@
+import { Vector } from '../types/vector';
+import { DisplayProcessor } from '../types';
+import { formattedValueToString } from '../valueFormats';
+import { vectorToArray } from './vectorToArray';
+
+export class FormattedVector<T = any> implements Vector<string> {
+  constructor(private source: Vector<T>, private formatter: DisplayProcessor) {}
+
+  get length() {
+    return this.source.length;
+  }
+
+  get(index: number): string {
+    const v = this.source.get(index);
+    return formattedValueToString(this.formatter(v));
+  }
+
+  toArray(): string[] {
+    return vectorToArray(this);
+  }
+
+  toJSON(): string[] {
+    return this.toArray();
+  }
+}

packages/grafana-data/src/vector/index.ts

@@ -4,5 +4,6 @@ export * from './CircularVector';
 export * from './ConstantVector';
 export * from './BinaryOperationVector';
 export * from './SortedVector';
+export * from './FormattedVector';
 
 export { vectorator } from './FunctionalVector';