Refactored app loading and refreshed documentation

Mark Gibbs · Mark Gibbs · commit a47bd768eaab · 2018-05-14T12:55:42.000-07:00
diff --git a/README.md b/README.md
@@ -88,21 +88,6 @@ def callback_color(dropdown_value):
 def callback_size(dropdown_color, dropdown_size):
     return "The chosen T-shirt is a %s %s one." %(dropdown_size,
                                                   dropdown_color)
-
-a2 = DelayedDash("Ex2")
-a2.layout = html.Div([
-    dcc.RadioItems(id="dropdown-one",options=[{'label':i,'value':j} for i,j in [
-    ("O2","Oxygen"),("N2","Nitrogen"),]
-    ],value="Oxygen"),
-    html.Div(id="output-one")
-    ])
-
-@a2.callback(
-    dash.dependencies.Output('output-one','children'),
-    [dash.dependencies.Input('dropdown-one','value')]
-    )
-def callback_c(*args,**kwargs):
-    return "Args are %s and kwargs are %s" %("".join(*args),str(kwargs))
 ```
 
 Note that the `DelayedDash` constructor requires a name to be specified. This name is then used to identify the dash app in
@@ -111,7 +96,7 @@ templates:
 ```jinja2
 {% load plotly_dash %}
 
-{% plotly_item "SimpleExample" %}
+{% plotly_item name="SimpleExample" %}
 ```
 
 The registration code needs to be in a location
diff --git a/demo/demo/templates/index.html b/demo/demo/templates/index.html
@@ -5,15 +5,15 @@
 <body>
   <div>
     Content here
-    {%plotly_item "simpleexample-1" ratio=0.2 %}
+    {%plotly_app slug="simpleexample-1" ratio=0.2 %}
   </div>
   <div>
     Content here
-    {%plotly_item "SimpleExample"%}
+    {%plotly_app name="SimpleExample"%}
   </div>
   <div>
     Content here
-    {%plotly_item "Ex2"%}
+    {%plotly_app name="Ex2"%}
   </div>
   </body>
 </html>
diff --git a/django_plotly_dash/dash_wrapper.py b/django_plotly_dash/dash_wrapper.py
@@ -13,43 +13,17 @@
 uid_counter = 0
 
 usable_apps = {}
-nd_apps = {}
 
 def add_usable_app(name, app):
     global usable_apps
     usable_apps[name] = app
 
-def add_instance(id, instance):
-    global nd_apps
-    nd_apps[id] = instance
-
-def get_app_by_name(name):
+def get_stateless_by_name(name):
     '''
     Locate a registered dash app by name, and return a DelayedDash instance encapsulating the app.
     '''
-    return usable_apps.get(name,None)
-
-def get_app_instance_by_id(id):
-    '''
-    Locate an instance of a dash app by identifier, or return None if one does not exist
-    '''
-    return nd_apps.get(id,None)
-
-def clear_app_instance(id):
-    try:
-        del nd_apps[id]
-    except:
-        pass
-
-def get_or_form_app(id, name, **kwargs):
-    '''
-    Locate an instance of a dash app by identifier, loading or creating a new instance if needed
-    '''
-    app = get_app_instance_by_id(id)
-    if app:
-        return app
-    dd = get_app_by_name(name)
-    return dd.form_dash_instance()
+    # TODO wrap this in raising a 404 if not found
+    return usable_apps[name]
 
 class Holder:
     def __init__(self):
@@ -78,9 +52,20 @@ def __init__(self, name=None, **kwargs):
 
         self._expanded_callbacks = False
 
+    def as_dash_instance(self):
+        '''
+        Form a dash instance, for stateless use of this app
+        '''
+        return self.form_dash_instance()
+
     def form_dash_instance(self, replacements=None, specific_identifier=None):
+        if not specific_identifier:
+            app_pathname = "%s:app-%s"% (app_name, main_view_label)
+        else:
+            app_pathname="%s:%s" % (app_name, main_view_label)
+
         rd = NotDash(name_root=self._uid,
-                     app_pathname="%s:%s" % (app_name, main_view_label),
+                     app_pathname=app_pathname,
                      expanded_callbacks = self._expanded_callbacks,
                      replacements = replacements,
                      specific_identifier = specific_identifier)
@@ -134,8 +119,6 @@ def __init__(self, name_root, app_pathname=None, replacements = None, specific_i
         else:
             self._uid = name_root
 
-        add_instance(self._uid, self)
-
         self._flask_app = Flask(self._uid)
         self._notflask = NotFlask()
         self._base_pathname = reverse(app_pathname,kwargs={'id':self._uid})
@@ -295,4 +278,3 @@ def dispatch_with_args(self, body, argMap):
 
         return self.callback_map[target_id]['callback'](*args,**argMap)
 
-
diff --git a/django_plotly_dash/models.py b/django_plotly_dash/models.py
@@ -2,7 +2,7 @@
 from django.contrib import admin
 from django.utils.text import slugify
 
-from .dash_wrapper import get_app_instance_by_id, get_app_by_name, clear_app_instance
+from .dash_wrapper import get_stateless_by_name
 
 import json
 
@@ -27,46 +27,25 @@ def save(self, *args, **kwargs):
         if not self.slug or len(self.slug) < 2:
             self.slug = slugify(self.instance_name)
         super(DashApp, self).save(*args,**kwargs)
-        # TODO at this point should invaliate any local cache of the older values
-        clear_app_instance(self.slug)
+
+    def _stateless_dash_app(self):
+        # TODO make this a property of the object
+        dd = get_stateless_by_name(self.app_name)
+        return dd
 
     def as_dash_instance(self):
-        ai = get_app_instance_by_id(self.slug)
-        if ai:
-            return ai
-        dd = get_app_by_name(self.app_name)
+        dd = self._stateless_dash_app()
         base = json.loads(self.base_state)
         return dd.form_dash_instance(replacements=base,
                                      specific_identifier=self.slug)
 
-    @staticmethod
-    def get_app_instance(id):
-        '''
-        Locate an application instance by id, either in local cache or in Database.
-        If in neither, then create a new instance assuming that the id is the app name.
-        '''
-        local_instance = get_app_instance_by_id(id)
-        if local_instance:
-            return local_instance
-        try:
-            return DashApp.objects.get(slug=id).as_dash_instance()
-        except:
-            pass
-
-        # Really no luck at all!
-        dd = get_app_by_name(id)
-        return dd.form_dash_instance()
-
     def _get_base_state(self):
         '''
         Get the base state of the object, as defined by the app.layout code, as a python dict
         '''
-        # Get base layout response, from a base object
-        base_app_inst = get_app_instance_by_id(self.app_name)
-        if not base_app_inst:
-            base_app = get_app_by_name(self.app_name)
-            base_app_inst = base_app.form_dash_instance()
+        base_app_inst = self._stateless_dash_app()
 
+        # Get base layout response, from a base object
         base_resp = base_app_inst.locate_endpoint_function('dash-layout')()
 
         base_obj = json.loads(base_resp.data.decode('utf-8'))
diff --git a/django_plotly_dash/templatetags/plotly_dash.py b/django_plotly_dash/templatetags/plotly_dash.py
@@ -1,11 +1,13 @@
 from django import template
+from django.shortcuts import get_object_or_404
 
 register = template.Library()
 
 from django_plotly_dash.models import DashApp
+from django_plotly_dash.dash_wrapper import get_stateless_by_name
 
 @register.inclusion_tag("django_plotly_dash/plotly_item.html", takes_context=True)
-def plotly_item(context, app_name, ratio=0.1, use_frameborder=False):
+def plotly_app(context, name=None, slug=None, ratio=0.1, use_frameborder=False):
 
     fbs = use_frameborder and '1' or '0'
 
@@ -24,6 +26,13 @@ def plotly_item(context, app_name, ratio=0.1, use_frameborder=False):
     height: 100%;
     """
 
-    app = DashApp.get_app_instance(app_name)
+    if name is not None:
+        da = get_stateless_by_name(name)
+        app = da.form_dash_instance()
+
+    if slug is not None:
+        da = get_object_or_404(DashApp,slug=slug)
+        app = da.as_dash_instance()
 
     return locals()
+
diff --git a/django_plotly_dash/urls.py b/django_plotly_dash/urls.py
@@ -6,11 +6,16 @@
 from .app_name import app_name, main_view_label
 
 urlpatterns = [
-    path('<slug:id>_dash-routes', routes, name="routes"),
-    path('<slug:id>_dash-layout', layout, name="layout"),
-    path('<slug:id>_dash-dependencies', dependencies, name="dependencies"),
-    path('<slug:id>_dash-update-component', csrf_exempt(update), name="update-component"),
+    path('instance/<slug:id>_dash-routes', routes, name="routes"),
+    path('instance/<slug:id>_dash-layout', layout, name="layout"),
+    path('instance/<slug:id>_dash-dependencies', dependencies, name="dependencies"),
+    path('instance/<slug:id>_dash-update-component', csrf_exempt(update), name="update-component"),
+    path('instance/<slug:id>', main_view, name=main_view_label),
 
-    path('<slug:id>', main_view, name=main_view_label),
+    path('app/<slug:id>_dash-routes', routes, {'stateless':True}, name="app-routes"),
+    path('app/<slug:id>_dash-layout', layout, {'stateless':True}, name="app-layout"),
+    path('app/<slug:id>_dash-dependencies', dependencies, {'stateless':True}, name="app-dependencies"),
+    path('app/<slug:id>_dash-update-component', csrf_exempt(update), {'stateless':True}, name="app-update-component"),
+    path('app/<slug:id>', main_view, {'stateless':True}, name='app-%s'%main_view_label),
     ]
 
diff --git a/django_plotly_dash/views.py b/django_plotly_dash/views.py
@@ -1,29 +1,46 @@
-from django.shortcuts import render
+from django.shortcuts import render, get_object_or_404
 from django.http import HttpResponse
 
 import json
 
 from .models import DashApp
+from .dash_wrapper import get_stateless_by_name
 
 def routes(*args,**kwargs):
-    pass
+    raise NotImplementedError
+
+def dependencies(request, id, stateless=False, **kwargs):
+    if stateless:
+        da = get_stateless_by_name(id)
+    else:
+        da = get_object_or_404(DashApp,slug=id)
+
+    app = da.as_dash_instance()
 
-def dependencies(request, id, **kwargs):
-    app = DashApp.get_app_instance(id)
     with app.app_context():
         mFunc = app.locate_endpoint_function('dash-dependencies')
         resp = mFunc()
         return HttpResponse(resp.data,
                             content_type=resp.mimetype)
 
-def layout(request, id, **kwargs):
-    app = DashApp.get_app_instance(id)
+def layout(request, id, stateless=False, **kwargs):
+    if stateless:
+        da = get_stateless_by_name(id)
+    else:
+        da = get_object_or_404(DashApp,slug=id)
+    app = da.as_dash_instance()
+
     mFunc = app.locate_endpoint_function('dash-layout')
     resp = mFunc()
     return app.augment_initial_layout(resp)
 
-def update(request, id, **kwargs):
-    app = DashApp.get_app_instance(id)
+def update(request, id, stateless=False, **kwargs):
+    if stateless:
+        da = get_stateless_by_name(id)
+    else:
+        da = get_object_or_404(DashApp,slug=id)
+    app = da.as_dash_instance()
+
     rb = json.loads(request.body.decode('utf-8'))
 
     if app.use_dash_dispatch():
@@ -44,8 +61,13 @@ def update(request, id, **kwargs):
     return HttpResponse(resp.data,
                         content_type=resp.mimetype)
 
-def main_view(request, id, **kwargs):
-    app = DashApp.get_app_instance(id)
+def main_view(request, id, stateless=False, **kwargs):
+    if stateless:
+        da = get_stateless_by_name(id)
+    else:
+        da = get_object_or_404(DashApp,slug=id)
+    app = da.as_dash_instance()
+
     mFunc = app.locate_endpoint_function()
     resp = mFunc()
     return HttpResponse(resp)
diff --git a/docs/simple_use.rst b/docs/simple_use.rst
@@ -52,7 +52,7 @@ templates:::
 
   {%load plotly_dash%}
 
-  {%plotly_item "SimpleExample"%}
+  {%plotly_item name="SimpleExample"%}
 
 The registration code needs to be in a location
 that will be imported into the Django process before any model or
