Make the cookie_path an attribute on trans so that consumers don't need

to duplicate logic. Unfortunately it isn't usable for the proxy setup
since trans isn't available when the command line is generated.

lib/galaxy/visualization/plugins/interactive_environments.py

@@ -88,7 +88,7 @@ class InteractiveEnvironmentRequest(object):
             self.attr.proxy_prefix = '/'.join(
                 (
                     '',
-                    (self.attr.galaxy_config.cookie_path or '/').strip('/'),
+                    trans.cookie_path.strip('/'),
                     self.attr.galaxy_config.dynamic_proxy_prefix.strip('/'),
                     self.attr.viz_id,
                 )

lib/galaxy/web/framework/webapp.py

@@ -620,12 +620,16 @@ class GalaxyWebTransaction(base.DefaultWebTransaction,
             # self.log_event( "Automatically created account '%s'", user.email )
         return user
 
+    @property
+    def cookie_path(self):
+        return self.app.config.cookie_path or url_for('/')
+
     def __update_session_cookie(self, name='galaxysession'):
         """
         Update the session cookie to match the current session.
         """
         self.set_cookie(self.security.encode_guid(self.galaxy_session.session_key),
-                        name=name, path=self.app.config.cookie_path or url_for('/'))
+                        name=name, path=self.cookie_path)
 
     def check_user_library_import_dir(self, user):
         if getattr(self.app.config, "user_library_import_dir_auto_creation", False):

lib/galaxy/web/proxy/__init__.py

@@ -13,6 +13,7 @@ from galaxy.util import (
 )
 from galaxy.util.filelock import FileLock
 from galaxy.util.lazy_process import LazyProcess, NoOpLazyProcess
+from galaxy.web.framework import url_for
 
 log = logging.getLogger(__name__)
 
@@ -148,7 +149,7 @@ class GolangProxyLauncher(object):
                 config.dynamic_proxy_bind_port,
             ),
             "--listenPath", "/".join((
-                (config.cookie_path or '/'),
+                (config.cookie_path or url_for('/')),
                 config.dynamic_proxy_prefix
             )),
             "--cookieName", "galaxysession",