close #2166 - add support for cursor api (#2217)

packages/search/lib/commands/AGGREGATE_WITHCURSOR.ts

@@ -0,0 +1,44 @@
+import {
+    AggregateOptions,
+    AggregateRawReply,
+    AggregateReply,
+    transformArguments as transformAggregateArguments,
+    transformReply as transformAggregateReply
+} from './AGGREGATE';
+
+export { FIRST_KEY_INDEX, IS_READ_ONLY } from './AGGREGATE';
+
+interface AggregateWithCursorOptions extends AggregateOptions {
+    COUNT?: number;
+}
+
+export function transformArguments(
+    index: string,
+    query: string,
+    options?: AggregateWithCursorOptions
+) {
+    const args = transformAggregateArguments(index, query, options);
+
+    args.push('WITHCURSOR');
+    if (options?.COUNT) {
+        args.push('COUNT', options.COUNT.toString());
+    }
+
+    return args;
+}
+
+type AggregateWithCursorRawReply = [
+    result: AggregateRawReply,
+    cursor: number
+];
+
+interface AggregateWithCursorReply extends AggregateReply {
+    cursor: number;
+}
+
+export function transformReply(reply: AggregateWithCursorRawReply): AggregateWithCursorReply {
+    return {
+        ...transformAggregateReply(reply[0]),
+        cursor: reply[1]
+    };
+}