Fix auto-refresh in tree view When webserver ui is not in / (apac…

…he#16018)

Co-authored-by: Felipe Lolas <felipe.lolas@bci.cl>

Obtain tree_data object endpoint from meta.
closes: apache#16017

(cherry picked from commit c288957)

airflow/www/static/js/tree.js

@@ -27,6 +27,7 @@ import getMetaValue from './meta_value';
 
 // dagId comes from dag.html
 const dagId = getMetaValue('dag_id');
+const treeDataUrl = getMetaValue('tree_data');
 
 function toDateString(ts) {
   const dt = new Date(ts * 1000);
@@ -409,7 +410,7 @@ document.addEventListener('DOMContentLoaded', () => {
 
   function handleRefresh() {
     $('#loading-dots').css('display', 'inline-block');
-    $.get(`/object/tree_data?dag_id=${dagId}`)
+    $.get(`${treeDataUrl}?dag_id=${dagId}`)
       .done(
         (runs) => {
           const newData = {

airflow/www/templates/airflow/dag.html

@@ -35,6 +35,7 @@
   <meta name="external_log_url" content="{{ url_for('Airflow.redirect_to_external_log') }}">
   <meta name="extra_links_url" content="{{ url_for('Airflow.extra_links') }}">
   <meta name="paused_url" content="{{ url_for('Airflow.paused') }}">
+  <meta name="tree_data" content="{{ url_for('Airflow.tree_data') }}">
   {% if show_external_log_redirect is defined %}
     <meta name="show_external_log_redirect" content="{{ show_external_log_redirect }}">
   {% endif %}