route logic for trailing slash

sanic/app.py

@@ -270,6 +270,9 @@ class Sanic:
                     'Endpoint with name `{}` was not found'.format(
                         view_name))
 
+        if uri.endswith('/'):
+            uri = uri[:-1]
+
         out = uri
 
         # find all the parameters we will need to build in the URL

sanic/router.py

@@ -96,6 +96,20 @@ class Router:
         return name, _type, pattern
 
     def add(self, uri, methods, handler, host=None):
+        # add regular version
+        self._add(uri, methods, handler, host)
+        slash_is_missing = (not uri[-1].endswith('/')
+                            and not self.routes_all.get(uri + '/', False))
+        without_slash_is_missing = (not self.routes_all.get(uri[:-1], False)
+                                    and uri is not '/')
+        # add version with trailing slash
+        if slash_is_missing:
+            self._add(uri + '/', methods, handler, host)
+        # add version without trailing slash
+        elif without_slash_is_missing:
+            self._add(uri[:-1], methods, handler, host)
+
+    def _add(self, uri, methods, handler, host=None):
         """Add a handler to the route list
 
         :param uri: path to match
@@ -105,7 +119,6 @@ class Router:
             When executed, it should provide a response object.
         :return: Nothing
         """
-
         if host is not None:
             if isinstance(host, str):
                 uri = host + uri

tests/test_routes.py

@@ -22,6 +22,19 @@ def test_shorthand_routes_get():
     request, response = app.test_client.post('/get')
     assert response.status == 405
 
+def test_route_optional_slash():
+    app = Sanic('test_route_optional_slash')
+
+    @app.get('/get')
+    def handler(request):
+        return text('OK')
+
+    request, response = app.test_client.get('/get')
+    assert response.text == 'OK'
+
+    request, response = app.test_client.get('/get/')
+    assert response.text == 'OK'
+
 def test_shorthand_routes_post():
     app = Sanic('test_shorhand_routes_post')