feat(ais-dynamic-widgets): add implementation (#922)

* feat(ais-dynamic-widgets): add implementation

Adds a new widget _ais-experimental-dynamic-widgets_ that can be used to conditionally render other widgets. This condition is based on the search results. At the moment there isn't yet a default way to enforce facet ordering in the Algolia engine, thus the data available to `transformItems` is an empty array. This will change once the Algolia engine adds support for facet ordering and this widget will move out of experimental mode.

```vue
<template>
  <ais-experimental-dynamic-widgets :transform-items="transformItems">
    <ais-refinement-list attribute="test1" />
    <ais-menu attribute="test2" />
    <ais-panel>
      <ais-hierarchical-menu :attributes="hierarchicalAttributes" />
    </ais-panel>
  </ais-experimental-dynamic-widgets>
</template>

<script>
export default {
  data() {
    return {
      hierarchicalAttributes: ["test3", "unused"],
    };
  },
  methods: {
    transformItems(_attributes, { results }) {
      // add a condition based on the results, eg. if you add the ordering via a query rule:
      return results.userData[0].facetOrdering;
    }
  },
};
</script>
```

See also: algolia/instantsearch#4687


Co-authored-by: Clément Vannicatte <20689156+shortcuts@users.noreply.github.com>

package.json

@@ -46,7 +46,7 @@
   },
   "dependencies": {
     "algoliasearch-helper": "^3.1.0",
-    "instantsearch.js": "^4.20.0"
+    "instantsearch.js": "^4.25.0"
   },
   "peerDependencies": {
     "algoliasearch": ">= 3.32.0 < 5",
@@ -114,11 +114,11 @@
   "bundlesize": [
     {
       "path": "./dist/vue-instantsearch.js",
-      "maxSize": "53.00 kB"
+      "maxSize": "54 kB"
     },
     {
       "path": "./dist/vue-instantsearch.common.js",
-      "maxSize": "16.50 kB"
+      "maxSize": "16.75 kB"
     }
   ],
   "resolutions": {

src/__tests__/index.js

@@ -34,6 +34,8 @@ it('should have `name` the same as the suit class name everywhere', () => {
     expect(installedName).toBe(name);
     if (name === 'AisInstantSearchSsr') {
       expect(suitClass).toBe(`ais-InstantSearch`);
+    } else if (name === 'AisExperimentalDynamicWidgets') {
+      expect(suitClass).toBe(`ais-DynamicWidgets`);
     } else {
       expect(suitClass).toBe(`ais-${name.substr(3)}`);
     }

src/components/DynamicWidgets.js

@@ -0,0 +1,87 @@
+import { createWidgetMixin } from '../mixins/widget';
+import { EXPERIMENTAL_connectDynamicWidgets } from 'instantsearch.js/es/connectors';
+import { createSuitMixin } from '../mixins/suit';
+
+function getWidgetAttribute(vnode) {
+  const props = vnode.componentOptions && vnode.componentOptions.propsData;
+  if (props) {
+    if (props.attribute) {
+      return props.attribute;
+    }
+    if (Array.isArray(props.attributes)) {
+      return props.attributes[0];
+    }
+  }
+
+  const children =
+    vnode.componentOptions && vnode.componentOptions.children
+      ? vnode.componentOptions.children
+      : vnode.children;
+
+  if (Array.isArray(children)) {
+    // return first child with a truthy attribute
+    return children.reduce(
+      (acc, curr) => acc || getWidgetAttribute(curr),
+      undefined
+    );
+  }
+
+  return undefined;
+}
+
+export default {
+  name: 'AisExperimentalDynamicWidgets',
+  mixins: [
+    createWidgetMixin({ connector: EXPERIMENTAL_connectDynamicWidgets }),
+    createSuitMixin({ name: 'DynamicWidgets' }),
+  ],
+  props: {
+    transformItems: {
+      type: Function,
+      default: undefined,
+    },
+  },
+  render(createElement) {
+    const components = new Map();
+    (this.$slots.default || []).forEach(vnode => {
+      const attribute = getWidgetAttribute(vnode);
+      if (attribute) {
+        components.set(
+          attribute,
+          createElement(
+            'div',
+            { key: attribute, class: [this.suit('widget')] },
+            [vnode]
+          )
+        );
+      }
+    });
+
+    // by default, render everything, but hidden so that the routing doesn't disappear
+    if (!this.state) {
+      const allComponents = [];
+      components.forEach(component => allComponents.push(component));
+
+      return createElement(
+        'div',
+        { attrs: { hidden: true }, class: [this.suit()] },
+        allComponents
+      );
+    }
+
+    return createElement(
+      'div',
+      { class: [this.suit()] },
+      this.state.attributesToRender.map(attribute => components.get(attribute))
+    );
+  },
+  computed: {
+    widgetParams() {
+      return {
+        transformItems: this.transformItems,
+        // we do not pass "widgets" to the connector, since Vue is in charge of rendering
+        widgets: [],
+      };
+    },
+  },
+};