fix: filters query params (#515)

Author: lukasvinclav

src/unfold/static/unfold/js/app.js

@@ -6,8 +6,27 @@ window.addEventListener("load", (e) => {
   dateTimeShortcutsOverlay();
 
   renderCharts();
+
+  filterForm();
 });
 
+/*************************************************************
+ * Filter form
+ *************************************************************/
+const filterForm = () => {
+  const filterForm = document.getElementById("filter-form");
+
+  if (!filterForm) {
+    return;
+  }
+
+  filterForm.addEventListener("formdata", (event) => {
+    Array.from(event.formData.entries()).forEach(([key, value]) => {
+      if (value === "") event.formData.delete(key);
+    });
+  });
+};
+
 /*************************************************************
  * Class watcher
  *************************************************************/

src/unfold/templates/unfold/change_list_filter.html

@@ -21,7 +21,7 @@ <h3 class="border-b flex font-medium mb-6 px-6 py-4 text-gray-700 text-sm dark:t
 
             <div class="px-6{% if cl.model_admin.list_filter_submit %} pb-16{% endif %}">
                 {% if cl.model_admin.list_filter_submit %}
-                    <form method="get">
+                    <form id="filter-form" method="get">
                 {% endif %}