Wait until JS dependency is loaded before rendering (#1577)

holoviz · Sep 13, 2020 · 4eb973e · 4eb973e
1 parent 2b9c98f
commit 4eb973e
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Showing 3 changed files with 17 additions and 2 deletions.
diff --git a/panel/_templates/doc_nb_js.js b/panel/_templates/doc_nb_js.js
@@ -4,12 +4,12 @@
     var render_items = {{ render_items }};
     root.Bokeh.embed.embed_items_notebook(docs_json, render_items);
   }
-  if (root.Bokeh !== undefined && root.Bokeh.Panel !== undefined) {
+  if (root.Bokeh !== undefined && root.Bokeh.Panel !== undefined{% for req in requirements %} && root['{{ req }}'] !== undefined {% endfor %}) {
     embed_document(root);
   } else {
     var attempts = 0;
     var timer = setInterval(function(root) {
-      if (root.Bokeh !== undefined && root.Bokeh.Panel !== undefined) {
+      if (root.Bokeh !== undefined && root.Bokeh.Panel !== undefined{% for req in requirements %} && root['{{ req }}'] !== undefined{% endfor %}) {
         clearInterval(timer);
         embed_document(root);
       } else if (document.readyState == "complete") {

diff --git a/panel/config.py b/panel/config.py
@@ -412,6 +412,17 @@ class panel_extension(_pyviz_extension):
                 'echarts': 'panel.models.echarts',
                 'ipywidgets': 'ipywidgets_bokeh.widget'}
 
+    # Check whether these are loaded before rendering
+    _globals = {
+        'deckgl': 'deck',
+        'echarts': 'echarts',
+        'katex': 'katex',
+        'mathjax': 'MathJax',
+        'plotly': 'Plotly',
+        'vega': 'vega',
+        'vtk': 'vtk'
+    }
+
     _loaded_extensions = []
 
     def __call__(self, *args, **params):

diff --git a/panel/io/notebook.py b/panel/io/notebook.py
@@ -129,15 +129,19 @@ def render_template(document, comm=None, manager=None):
 def render_model(model, comm=None):
     if not isinstance(model, Model):
         raise ValueError("notebook_content expects a single Model instance")
+    from ..config import panel_extension as pnext
 
     target = model.ref['id']
 
     (docs_json, [render_item]) = standalone_docs_json_and_render_items([model], True)
     div = div_for_render_item(render_item)
     render_item = render_item.to_json()
+    requirements = [pnext._globals[ext] for ext in pnext._loaded_extensions
+                    if ext in pnext._globals]
     script = DOC_NB_JS.render(
         docs_json=serialize_json(docs_json),
         render_items=serialize_json([render_item]),
+        requirements=requirements
     )
     bokeh_script, bokeh_div = script, div
     html = "<div id='{id}'>{html}</div>".format(id=target, html=bokeh_div)