Remove legacy example, add option to link remote script sources

config/plugins/visualizations/common/templates/script_entry_point.mako

@@ -5,6 +5,7 @@
 <%def name="stylesheets()">
     <% css = script_attributes.get("css") %>
     %if css is not None:
+        <% css = css if h.is_url(css) else f"{static_url}{css}" %>
         <link rel="stylesheet" href="${css}">
     %endif
 </%def>
@@ -29,6 +30,7 @@
 
     ## Add script tag
     <% script_src = script_attributes.get("src") %>
+    <% script_src = script_src if h.is_url(script_src) else f"{static_url}{script_src}" %>
     <% script_type = script_attributes.get("type") or "module" %>
     <script type="${script_type}" src="${script_src}"></script>
 </%def>

lib/galaxy/app_unittest_utils/galaxy_mock.py

@@ -439,5 +439,8 @@ def dumps(*kwargs):
     def js(*js_files):
         pass
 
+    def is_url(*kwargs):
+        return True
+
     def url_for(*kwargs):
         return "/"

lib/galaxy/web/framework/helpers/__init__.py

@@ -6,6 +6,7 @@
 GalaxyWebTransaction in galaxy/webapps/base/webapp.py
 """
 
+import re
 from datetime import (
     datetime,
     timedelta,
@@ -105,6 +106,17 @@ def is_true(val):
     return val is True or val in ["True", "true", "T", "t"]
 
 
+def is_url(val):
+    """
+    Regular expression to match common URL protocols
+    """
+    if val is not None:
+        url_pattern = re.compile(r"^(https?:\/\/|ftp:\/\/)")
+        return bool(url_pattern.match(val))
+    else:
+        return False
+
+
 def to_js_bool(val):
     """
     Prints javascript boolean for passed value.