move initialization of options_form to __init__

etc/byor_config.py

@@ -3,7 +3,3 @@
 load_subconfig('etc/github_auth.py')
 
 c.JupyterHub.spawner_class = 'everware.ByorDockerSpawner'
-
-from os.path import join as pjoin
-with open(pjoin(c.JupyterHub.template_paths[0], '_byor_options_form.html')) as form:
-    c.ByorDockerSpawner.options_form = form.read()

everware/__init__.py

@@ -1,4 +1,4 @@
-__version__ = "0.11.0"
+__version__ = "0.12.0"
 from .spawner import *
 from .byor_spawner import *
 from .authenticator import *

everware/byor_spawner.py

@@ -1,3 +1,5 @@
+from os.path import join as pjoin
+
 import docker
 from docker.errors import DockerException
 from traitlets import Int
@@ -7,9 +9,16 @@
 
 
 class ByorDockerSpawner(CustomDockerSpawner):
+
+    _options_form_is_initialized = False
     def __init__(self, **kwargs):
-        self._byor_client = None
         CustomDockerSpawner.__init__(self, **kwargs)
+        self._byor_client = None
+        if not self._options_form_is_initialized:
+            with open(pjoin(self.config['JupyterHub']['template_paths'][0],
+                            '_byor_options_form.html')) as form:
+                ByorDockerSpawner.options_form = form.read()
+                ByorDockerSpawner._options_form_is_initialized = True
 
     @property
     def client(self):