Made show_messages available to plugins, closes #864

datasette/app.py

@@ -739,6 +739,7 @@ async def render_template(
                 "zip": zip,
                 "body_scripts": body_scripts,
                 "format_bytes": format_bytes,
+                "show_messages": lambda: self._show_messages(request),
                 "extra_css_urls": self._asset_urls("extra_css_urls", template, context),
                 "extra_js_urls": self._asset_urls("extra_js_urls", template, context),
                 "base_url": self.config("base_url"),

datasette/views/base.py

@@ -92,7 +92,6 @@ async def render(self, templates, request, context=None):
             **{
                 "database_url": self.database_url,
                 "database_color": self.database_color,
-                "show_messages": lambda: self.ds._show_messages(request),
                 "select_templates": [
                     "{}{}".format(
                         "*" if template_name == template.name else "", template_name

tests/plugins/my_plugin.py

@@ -192,10 +192,13 @@ def not_async():
 
     def add_message(datasette, request):
         datasette.add_message(request, "Hello from messages")
-        print("Adding message")
-        print(request._messages)
         return Response.html("Added message")
 
+    async def render_message(datasette, request):
+        return Response.html(
+            await datasette.render_template("render_message.html", request=request)
+        )
+
     return [
         (r"/one/$", one),
         (r"/two/(?P<name>.*)$", two),
@@ -204,6 +207,7 @@ def add_message(datasette, request):
         (r"/csrftoken-form/$", csrftoken_form),
         (r"/not-async/$", not_async),
         (r"/add-message/$", add_message),
+        (r"/render-message/$", render_message),
     ]
 
 

tests/test_plugins.py

@@ -610,6 +610,16 @@ def test_register_routes_add_message(app_client):
     assert [["Hello from messages", 1]] == decoded
 
 
+def test_register_routes_render_message(restore_working_directory, tmpdir_factory):
+    templates = tmpdir_factory.mktemp("templates")
+    (templates / "render_message.html").write_text('{% extends "base.html" %}', "utf-8")
+    with make_app_client(template_dir=templates) as client:
+        response1 = client.get("/add-message/")
+        response2 = client.get("/render-message/", cookies=response1.cookies)
+        assert 200 == response2.status
+        assert "Hello from messages" in response2.text
+
+
 @pytest.mark.asyncio
 async def test_startup(app_client):
     await app_client.ds.invoke_startup()