feat(Query): implement sortFacetValuesBy (#450)

* feat(Query): implement sortFacetValuesBy

* refactor(Query): sortFacetValuesBy as enum

* refactor(Query): sortFacetValuesBy using enum's toString

Author: PLNech

algoliasearch/src/main/java/com/algolia/search/saas/Query.java

@@ -82,6 +82,21 @@ public enum AlternativesAsExact {
         MULTI_WORDS_SYNONYM
     }
 
+    public enum SortFacetValuesBy {
+        ALPHA {
+            @Override
+            public String toString() {
+                return "alpha";
+            }
+        },
+        COUNT {
+            @Override
+            public String toString() {
+                return "count";
+            }
+        }
+    }
+
     // ----------------------------------------------------------------------
     // Construction
     // ----------------------------------------------------------------------
@@ -1209,9 +1224,10 @@ public String[] getRestrictSearchableAttributes() {
 
     /**
      * Set a list of contexts for which rules are enabled.
-     *
+     * <p>
      * Contextual rules matching any of these contexts are eligible, as well as generic rules.
      * When empty, only generic rules are eligible.
+     *
      * @param ruleContexts one or several contexts.
      */
     public @NonNull Query setRuleContexts(String... ruleContexts) {
@@ -1236,6 +1252,24 @@ public String[] getRestrictSearchableAttributes() {
         return get(KEY_SNIPPET_ELLIPSIS_TEXT);
     }
 
+    public static final String KEY_SORT_FACET_VALUES_BY = "sortFacetValuesBy";
+
+
+    /**
+     * When using {@link #setFacets}, Algolia retrieves a list of matching facet values for each faceted attribute.
+     * This parameter controls how the facet values are sorted within each faceted attribute.
+     *
+     * @param order supported options are `count` (sort by decreasing count) and `alpha` (sort by increasing alphabetical order)
+     * @return This instance (used to chain calls).
+     */
+    public @NonNull Query setSortFacetValuesBy(SortFacetValuesBy order) {
+        return set(KEY_SORT_FACET_VALUES_BY, order.toString());
+    }
+
+    public String getSortFacetValuesBy() {
+        return get(KEY_SORT_FACET_VALUES_BY);
+    }
+
     private static final String KEY_SYNONYMS = "synonyms";
 
     /**

algoliasearch/src/test/java/com/algolia/search/saas/QueryTest.java

@@ -278,6 +278,21 @@ public void analytics() {
         assertEquals(query.getAnalytics(), Query.parse(query.build()).getAnalytics());
     }
 
+
+    @Test
+    public void sortFacetValuesBy() {
+        Query query = new Query();
+        assertNull(query.getSortFacetValuesBy());
+        query.setSortFacetValuesBy(Query.SortFacetValuesBy.COUNT);
+        assertEquals("count", query.getSortFacetValuesBy());
+        assertEquals("count", query.get("sortFacetValuesBy"));
+        query.setSortFacetValuesBy(Query.SortFacetValuesBy.ALPHA);
+        assertEquals("alpha", query.getSortFacetValuesBy());
+        assertEquals("alpha", query.get("sortFacetValuesBy"));
+        Query query2 = Query.parse(query.build());
+        assertEquals(query.getSortFacetValuesBy(), query2.getSortFacetValuesBy());
+    }
+
     @Test
     public void synonyms() {
         Query query = new Query();