Moving from Rails to Django: Replacing flash[:notice]

One of the most common practices I came across while learning Rails is the flash[:notice] mechanism used to send (error) messages to the template. Consequently it was also one of my first targets to migrate when I started moving a pet application from Rails to Django.

I came up with a simple (and all too obvious) way to send error messages to the template. I am sure that there are better ways to do this. If you know of any, please take a minute to share them.

First, the Rails snippet.

view plainprint?

1. def index  
2.  ...  
3.  begin          
4.   army = Army.find(params[:army][:id])          
5.  rescue StandardError => se          
6.   flash[:notice] = "Vare, legiones redde!"          
7.   return      
8.  end      
9.  ...  
10. end  

def index ... begin army = Army.find(params[:army][:id]) rescue StandardError => se flash[:notice] = "Vare, legiones redde!" return end ... end Next, the equivalent in Django.

view plainprint?

1. from django.shortcuts import render_to_response  
2.   
3. def index(request):  
4.     ...  
5.     try:  
6.         army = Army.objects.get(id = request.POST["army"])  
7.   
8.     except ( KeyError, Army.DoesNotExist ):  
9.         return render_to_response( "some_template.html", { "flash" : "Vare, legiones redde!" } )  
10.     ...  

from django.shortcuts import render_to_response def index(request): ... try: army = Army.objects.get(id = request.POST["army"]) except ( KeyError, Army.DoesNotExist ): return render_to_response( "some_template.html", { "flash" : "Vare, legiones redde!" } ) ... The template in Rails ...

view plainprint?

1. ...  
2. <% if @flash[:notice] -%>  
3. <div id="flash">  
4.         <div><%= @flash[:notice] %></div>  
5. </div>  
6. <% end -%>  
7. ...  

... <% if @flash[:notice] -%> <div id="flash"> <div><%= @flash[:notice] %></div> </div> <% end -%> ... ... and the template in Django.

view plainprint?

1. ...  
2. {% if flash %}  
3. <div id="flash">  
4.         <div>{{ flash }}</div>  
5. </div>  
6. {% endif %}  
7. ...  

... {% if flash %} <div id="flash"> <div>{{ flash }}</div> </div> {% endif %} ... While testing in Django, flash can be treated just like any other context variable.