Added DashApp model with associated migration

Mark Gibbs · Mark Gibbs · commit eae96bb6e840 · 2018-05-10T16:25:53.000-07:00
diff --git a/demo/configdb.py b/demo/configdb.py
@@ -0,0 +1,17 @@
+#!/usr/bin/env python
+#
+# Create a new superuser
+from django.contrib.auth import get_user_model
+
+UserModel = get_user_model()
+
+name="admin"
+password="admin"
+
+try:
+    UserModel.objects.get(username=name)
+except:
+    su = UserModel.objects.create_user(name,password=password)
+    su.is_staff=True
+    su.is_superuser=True
+    su.save()
diff --git a/demo/demo/templates/index.html b/demo/demo/templates/index.html
@@ -5,7 +5,7 @@
 <body>
   <div>
     Content here
-    {%plotly_item "SimpleExample"%}
+    {%plotly_item "simpleexample-1"%}
   </div>
   <div>
     Content here
diff --git a/django_plotly_dash/admin.py b/django_plotly_dash/admin.py
@@ -1,3 +1,6 @@
 from django.contrib import admin
 
-# Register your models here.
+from .models import DashApp, DashAppAdmin
+
+admin.site.register(DashApp, DashAppAdmin)
+
diff --git a/django_plotly_dash/app_name.py b/django_plotly_dash/app_name.py
@@ -1 +1,2 @@
 app_name = "the_django_plotly_dash"
+main_view_label = "main"
diff --git a/django_plotly_dash/dash_wrapper.py b/django_plotly_dash/dash_wrapper.py
@@ -8,14 +8,21 @@
 
 from plotly.utils import PlotlyJSONEncoder
 
-from .app_name import app_name
+from .app_name import app_name, main_view_label
 
 uid_counter = 0
 
 usable_apps = {}
-app_instances = {}
 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):
     '''
     Locate a registered dash app by name, and return a DelayedDash instance encapsulating the app.
@@ -28,6 +35,9 @@ def get_app_instance_by_id(id):
     '''
     return nd_apps.get(id,None)
 
+def clear_app_instance(id):
+    del nd_apps[id]
+
 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
@@ -60,15 +70,17 @@ def __init__(self, name=None, **kwargs):
         self.css = Holder()
         self.scripts = Holder()
 
-        global usable_apps
-        usable_apps[self._uid] = self
+        add_usable_app(self._uid,
+                       self)
 
         self._expanded_callbacks = False
 
-    def form_dash_instance(self):
+    def form_dash_instance(self, replacements=None, specific_identifier=None):
         rd = NotDash(name_root=self._uid,
-                     app_pathname="%s:main" % app_name,
-                     expanded_callbacks = self._expanded_callbacks)
+                     app_pathname="%s:%s" % (app_name, main_view_label),
+                     expanded_callbacks = self._expanded_callbacks,
+                     replacements = replacements,
+                     specific_identifier = specific_identifier)
         rd.layout = self.layout
 
         for cb, func in self._callback_sets:
@@ -112,17 +124,14 @@ def run(self,*args,**kwargs):
         pass
 
 class NotDash(Dash):
-    def __init__(self, name_root, app_pathname=None, replacements = None, **kwargs):
+    def __init__(self, name_root, app_pathname=None, replacements = None, specific_identifier=None, expanded_callbacks=False, **kwargs):
 
-        global app_instances
-        current_instances = app_instances.get(name_root,None)
-
-        if current_instances is not None:
-            self._uid = "%s-%i" % (name_root,len(current_instances)+1)
-            current_instances.append(self)
+        if specific_identifier is not None:
+            self._uid = specific_identifier
         else:
             self._uid = name_root
-            app_instances[name_root] = [self,]
+
+        add_instance(self._uid, self)
 
         self._flask_app = Flask(self._uid)
         self._notflask = NotFlask()
@@ -132,11 +141,9 @@ def __init__(self, name_root, app_pathname=None, replacements = None, **kwargs):
         kwargs['server'] = self._notflask
 
         super(NotDash, self).__init__(**kwargs)
-        global nd_apps
-        nd_apps[self._uid] = self
 
         self._adjust_id = False
-        self._dash_dispatch = not kwargs.get('expanded_callbacks',False)
+        self._dash_dispatch = not expanded_callbacks
         if replacements:
             self._replacements = replacements
         else:
@@ -164,6 +171,8 @@ def augment_initial_layout(self, base_response):
                             content_type=base_response.mimetype)
 
     def walk_tree_and_replace(self, data):
+        # Walk the tree. Rely on json decoding to insert instances of dict and list
+        # ie we use a dna test for anatine, rather than our eyes and ears...
         if isinstance(data,dict):
             response = {}
             replacements = {}
diff --git a/django_plotly_dash/migrations/0001_initial.py b/django_plotly_dash/migrations/0001_initial.py
@@ -0,0 +1,26 @@
+# Generated by Django 2.0.5 on 2018-05-10 21:48
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='DashApp',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('app_name', models.CharField(max_length=100)),
+                ('instance_name', models.CharField(blank=True, max_length=100, unique=True)),
+                ('slug', models.SlugField(blank=True, max_length=110, unique=True)),
+                ('base_state', models.TextField()),
+                ('creation', models.DateTimeField(auto_now_add=True)),
+                ('update', models.DateTimeField(auto_now=True)),
+            ],
+        ),
+    ]
diff --git a/django_plotly_dash/migrations/__init__.py b/django_plotly_dash/migrations/__init__.py
diff --git a/django_plotly_dash/models.py b/django_plotly_dash/models.py
@@ -1,3 +1,63 @@
 from django.db import models
+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
+
+import json
+
+class DashApp(models.Model):
+    '''
+    An instance of this model represents a dash application and its internal state
+    '''
+    app_name = models.CharField(max_length=100, blank=False, null=False, unique=False)
+    instance_name = models.CharField(max_length=100, unique=True, blank=True, null=False)
+    slug = models.SlugField(max_length=110, unique=True, blank=True)
+    base_state = models.TextField(null=False) # If mandating postgresql then this could be a JSONField
+    creation = models.DateTimeField(auto_now_add=True)
+    update = models.DateTimeField(auto_now=True)
+
+    def __str__(self):
+        return self.instance_name
+
+    def save(self, *args, **kwargs):
+        if not self.instance_name:
+            existing_count = DashApp.objects.filter(app_name=self.app_name).count()
+            self.instance_name = "%s-%i" %(self.app_name, existing_count+1)
+        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 as_dash_instance(self):
+        ai = get_app_instance_by_id(self.slug)
+        if ai:
+            return ai
+        dd = get_app_by_name(self.app_name)
+        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()
+
+class DashAppAdmin(admin.ModelAdmin):
+    list_display = ['app_name','instance_name','slug','creation','update',]
+    list_filter = ['app_name','creation','update',]
 
-# Create your models here.
diff --git a/django_plotly_dash/templatetags/plotly_dash.py b/django_plotly_dash/templatetags/plotly_dash.py
@@ -2,11 +2,11 @@
 
 register = template.Library()
 
-from django_plotly_dash.dash_wrapper import get_or_form_app
+from django_plotly_dash.models import DashApp
 
 @register.inclusion_tag("django_plotly_dash/plotly_item.html", takes_context=True)
 def plotly_item(context, app_name):
 
-    app = get_or_form_app(app_name, app_name)
+    app = DashApp.get_app_instance(app_name)
 
     return locals()
diff --git a/django_plotly_dash/urls.py b/django_plotly_dash/urls.py
@@ -3,14 +3,14 @@
 
 from .views import routes, layout, dependencies, update, main_view
 
-from .app_name import app_name
+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('<slug:id>', main_view, name="main"),
+    path('<slug:id>', main_view, name=main_view_label),
     ]
 
diff --git a/django_plotly_dash/views.py b/django_plotly_dash/views.py
@@ -1,29 +1,29 @@
 from django.shortcuts import render
+from django.http import HttpResponse
 
 import json
 
-from .dash_wrapper import get_app_instance_by_id, get_or_form_app
-from django.http import HttpResponse
+from .models import DashApp
 
 def routes(*args,**kwargs):
     pass
 
 def dependencies(request, id, **kwargs):
-    app = get_app_instance_by_id(id)
+    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 = get_app_instance_by_id(id)
+    app = DashApp.get_app_instance(id)
     mFunc = app.locate_endpoint_function('dash-layout')
     resp = mFunc()
     return app.augment_initial_layout(resp)
 
 def update(request, id, **kwargs):
-    app = get_app_instance_by_id(id)
+    app = DashApp.get_app_instance(id)
     rb = json.loads(request.body.decode('utf-8'))
 
     if app.use_dash_dispatch():
@@ -46,7 +46,7 @@ def update(request, id, **kwargs):
                         content_type=resp.mimetype)
 
 def main_view(request, id, **kwargs):
-    app = get_or_form_app(id, id)
+    app = DashApp.get_app_instance(id)
     mFunc = app.locate_endpoint_function()
     resp = mFunc()
     return HttpResponse(resp)
diff --git a/prepare_demo b/prepare_demo
@@ -3,4 +3,5 @@
 source env/bin/activate
 cd demo
 ./manage.py migrate
+./manage.py shell < configdb.py # Add a superuser if needed
 ./manage.py runserver

Original file line number	Diff line number	Diff line change
`@@ -1 +1,2 @@`
`1`	`1`	`app_name = "the_django_plotly_dash"`
	`2`	`+main_view_label = "main"`