Rely on project version to set SW version

We create a new class view to handle the SW and pass proper context to the template.

djangopwa/__init__.py

+version = '1.0.1'

djangopwa/apps/pwa/views.py

 from django.http import Http404
 from django.shortcuts import render
+from django.views.generic import TemplateView
+
+from djangopwa import version
 
 
 def offline(request):
@@ -20,3 +23,14 @@ def say_something(request, key):
         raise Http404(f'{key} is not a valid thing to say')
 
     return render(request, 'pwa/say_something.html', context={'thing': things_to_say[key]})
+
+
+class ServiceWorkerView(TemplateView):
+    template_name = 'sw.js'
+    content_type = 'application/javascript'
+    name = 'sw.js'
+
+    def get_context_data(self, **kwargs):
+        return {
+            'version': version,
+        }

djangopwa/templates/sw.js

-const VERSION = '1.0.0';
+const VERSION = '{{ version }}';
 const staticCachePrefix = 'static';
 const staticCacheName = `${staticCachePrefix}-${VERSION}`;
 const dynamicCacheName = 'dynamic';

djangopwa/urls.py

@@ -15,8 +15,8 @@ Including another URLconf
 """
 from django.contrib import admin
 from django.urls import path
-from django.views.generic import TemplateView
 
+from . import version
 from .apps.pwa import views as pwa_views
 
 
@@ -32,7 +32,7 @@ urlpatterns = [
     # trick to make it work.
     path(
         'sw.js',
-        TemplateView.as_view(template_name='sw.js', content_type='application/javascript'),
-        name='sw.js',
+        pwa_views.ServiceWorkerView.as_view(),
+        name=pwa_views.ServiceWorkerView.name,
     ),
 ]