Welcome to the fifth lesson of our course on building an image generation service with Django! In our previous lessons, we've built several key components of our application: the PromptManager for formatting user inputs, the ImageManager for storing and processing images, the ImageGeneratorService for connecting to Google's Gemini API, and most recently, the ImageGeneratorController, which handles input validation and response formatting.

Now it's time to bring everything together by creating the Django application that will expose our functionality through HTTP endpoints. This is the final piece of our backend architecture that will allow users to interact with our image generation service through a web interface.

In the previous lesson, we built the ImageGeneratorView, which acts as an intermediary between our service layer and the views we'll create today. The view handles the business logic of validating inputs, calling the appropriate service methods, and formatting responses. Now, we'll create the HTML and endpoints that will receive HTTP requests from clients and pass them to our view.

Our Django API will have three main views:

1. A view to serve the main HTML page
2. An endpoint to handle image generation requests
3. An endpoint to retrieve all previously generated images

By the end of this lesson, you'll have a complete Django API that integrates with the controller we built previously, providing a clean interface for clients to generate and retrieve images.

Let's start by creating our Django project and app. We'll set up the basic structure and necessary configurations in settings.py and urls.py.

In this example, a project called myproject is already created, so you only have to create the app:

In myproject/settings.py, add image_generator to the INSTALLED_APPS list:

Next, configure the URL routing in myproject/urls.py:

Create a urls.py file in the image_generator app directory to define the app-specific URL patterns:

With these configurations, our Django application is ready to have views defined. The application will serve as the entry point for all client requests, routing them to the appropriate view functions based on the URL.

Now that we have our Django application set up, let's define the views that will handle client requests. We'll start with the index view, which will serve the main HTML page of our application:

In this view, we use the render function to return the image_generator.html template. Ensure that the template is located in the templates directory within the image_generator app.

Next, let's define the view for generating images:

This view handles POST requests to the /api/generate_image URL. We use @csrf_exempt to disable CSRF protection for simplicity, but in a real application, you should handle CSRF tokens appropriately. The view extracts user_input from the POST data and passes it to the controller's generate_image method, returning the response as JSON.

Finally, let's define the view for retrieving all previously generated images:

This view handles GET requests to the /api/get_images URL. It calls the controller's get_images method and returns the response as JSON.

With these three views, our Django API provides a complete interface for clients to interact with our image generation service. Clients can view the main page, generate new images, and retrieve previously generated ones.

Now that we have our Django application and views defined, let's configure the server to run our application. Use the following command to start the Django development server:

This command starts the Django development server on the default port 8000. You can access your application by opening a web browser and navigating to http://localhost:8000/.

The development server provides helpful error messages and automatically reloads when you make changes to your code. This is very useful during development but should be replaced with a production-ready server in a production environment.

In this lesson, we've built a complete Django API that integrates with our ImageGeneratorView to provide a web interface for our image generation service. Let's review what we've accomplished:

1. We set up a Django project and app with the necessary configurations in settings.py and urls.py.
2. We created an index view to serve the main HTML page of our application.
3. We implemented a POST view for generating images, which extracts user input from the request and passes it to our controller.
4. We set up a GET view for retrieving all previously generated images.
5. We configured the Django server to run on the default port with automatic reloading enabled for development.

Our Django API now provides a complete interface for clients to interact with our image generation service. The API views receive HTTP requests, extract the necessary data, and pass it to our controller, which handles the business logic of validating inputs, calling the appropriate service methods, and formatting responses.

This completes the server-side portion of our image generation application. We've built a robust, modular architecture with a clear separation of concerns:

• The PromptManager handles prompt formatting
• The ImageManager manages image storage and processing
• The ImageGeneratorService connects to the Gemini API and coordinates the other components
• The ImageGeneratorView validates inputs and formats responses

In the upcoming practice exercises, you'll have the opportunity to test the API views we've created. You'll send requests to generate images with different prompts and retrieve the stored images. You'll also explore how the API handles error cases, such as missing or invalid inputs.

By the end of these exercises, you'll have a solid understanding of how to build a complete web API with Django, integrating it with a controller-based architecture to provide a clean, consistent interface for clients. This knowledge will be valuable not just for image generation services but for any web application you build in the future.