Django Request Flow and User Interactions

Based on the information provided, you're encountering a fundamental issue with how HTTP requests and responses work in Django (and web applications in general).

The Issue

In Django, a single view function handles one HTTP request and returns one HTTP response. When your handle_standard_order function attempts to render a page for user input in the middle of processing, it doesn't actually pause execution and wait for user input. Instead, it would simply return that rendered page as the response for the entire request, ending the execution of your view function.

Why This Doesn't Work

The problem stems from the stateless nature of HTTP:

1. When you call render() in your helper function, it creates an HTTP response object
2. This response would be returned to the browser, ending the current request-response cycle
3. Your loops don't "pause" waiting for user input - they continue executing
4. Since the helper function doesn't actually return the rendered response to the main view, the render call has no effect

Solutions

You have several options to handle this workflow:

1. Multi-step Form Process

Break your process into multiple separate requests:

PYTHONCopied
def receive_delivery(request):
    if 'json_data' in request.POST:
        # Store the JSON data in the session
        request.session['delivery_data'] = json.loads(request.POST['json_data'])
        return redirect('process_first_order')
    
    # Initial form display
    return render(request, 'initial_form.html')

def process_first_order(request):
    # Get data from session
    delivery_data = request.session.get('delivery_data', {})
    
    if not delivery_data:
        return redirect('orders_home')
    
    # Get the first unprocessed order
    current_order = get_next_unprocessed_order(delivery_data)
    
    if not current_order:
        # All orders processed
        return redirect('orders_home')
    
    if request.method == 'POST':
        # Process the form submission for this order
        process_order_input(request.POST, current_order)
        # Mark this order as processed
        mark_order_processed(delivery_data, current_order)
        # Save updated data back to session
        request.session['delivery_data'] = delivery_data
        # Redirect to process the next order
        return redirect('process_first_order')
    
    # Display form for the current order
    return render(request, 'order_input_form.html', {'order': current_order})

2. AJAX/JavaScript Approach

Use JavaScript to handle the multi-step process on the client side:

1. Send all the JSON data to the browser initially
2. Use JavaScript to display each order's form one at a time
3. Collect all user inputs in the browser
4. Submit everything back to Django in a single request when complete

3. Django Messages Framework

For simpler interactions, you could use Django's messages framework to communicate with users between requests, though this wouldn't work for complex form inputs.

Important Note on Parallel Requests

Be aware that when using sessions to store state between requests, there can be issues with parallel requests as mentioned in the Django documentation:

Due to the way cookies (and hence sessions) work, the behavior of any backends that make use of cookies or sessions is undefined when the same client makes multiple requests that set or get messages in parallel.

This means you should design your UI to guide users through one step at a time rather than allowing multiple concurrent operations.

Conclusion

You cannot pause execution of a Django view to wait for user input in the middle of processing. Instead, you need to restructure your application to handle each user interaction as a separate HTTP request-response cycle, maintaining state between requests using sessions or other persistence mechanisms.