Add ability to pass in custom facet_by options

README.md

@@ -444,6 +444,37 @@ Read more about all available options for `renderingContent` in [Algolia's docum
   });
   ```
 
+### Setting `facet_by` options
+
+> Available as of typesense-instantsearch-adapter `2.8.0-1` and Typesense Server `v0.26.0.rc25`
+
+The `facet_by` parameter is managed by InstantSearch internally when you use the various filter widget.
+
+But if you need to pass custom options to the `facet_by` parameter (eg: server-side sort options), then you can use the `facetByOptions` parameter as shown below:
+
+```js
+const typesenseInstantsearchAdapter = new TypesenseInstantSearchAdapter({
+  server: {
+    apiKey: "xyz",
+    nodes: [
+      {
+        host: "localhost",
+        port: "8108",
+        path: "/",
+        protocol: "http",
+      },
+    ],
+  },
+  facetByOptions: {
+    brand: "(sort_by: _alpha:asc)",
+    category: "(sort_by: _alpha:desc)",
+  }, // <======= Add any facet_by parameter as a key value pair. Don't forget the surrounding parantheses in the value.
+  additionalSearchParameters,
+});
+```
+
+Note that for sorting in refinementLists, in addition to sorting on the Typesense Server-side, you'd also need to pass the [`sortBy`](https://www.algolia.com/doc/api-reference/widgets/refinement-list/js/#widget-param-sortby) parameter to the refinementList widget to also sort the results appropriately on the client-side. 
+
 ### Grouped Hits
 
 > Available as of typesense-instantsearch-adapter `2.7.1-4`

index.d.ts

@@ -89,6 +89,7 @@ interface BaseAdapterOptions {
   facetableFieldsWithSpecialCharacters?: string[];
   renderingContent?: object;
   flattenGroupedHits?: boolean;
+  facetByOptions?: object;
 }
 
 interface CollectionSearchParameters {

jest-puppeteer.config.js

@@ -1,8 +1,9 @@
+const isDebugMode = process.env.NODE_OPTIONS && process.env.NODE_OPTIONS.includes("javascript-debugger");
 module.exports = {
   launch: {
     dumpio: true,
     // headless: process.env.HEADLESS === "true" || process.env.CI === "true",
-    headless: true,
+    headless: isDebugMode ? false : true,
     slowMo: 10,
     defaultViewport: null,
     // devtools: true