Use Vary header in htmx views to fix caching issues (back button)

bolt-htmx/bolt/htmx/views.py

@@ -1,5 +1,7 @@
 import re
 
+from bolt.utils.cache import patch_vary_headers
+
 
 class HTMXViewMixin:
     htmx_template_name = ""
@@ -19,6 +21,13 @@ def render_template(self):
 
         return template.render(context)
 
+    def get_response(self):
+        response = super().get_response()
+        # Tell browser caching to also consider the fragment header,
+        # not just the url/cookie.
+        patch_vary_headers(response, ["HX-Request", "BHX-Fragment", "BHX-Action"])
+        return response
+
     def get_request_handler(self):
         if self.is_htmx_request:
             # You can use an htmx_{method} method on views