Angular Universal Application for Server-Side Rendering

This challenge focuses on building a basic Angular application that utilizes Angular Universal for server-side rendering (SSR). SSR improves initial load times, SEO, and provides a better user experience, especially on slower devices or networks. You'll be creating a simple component that displays a greeting message, and ensuring it renders correctly on both the client and server.

Problem Description

Your task is to create a minimal Angular application that leverages Angular Universal to perform server-side rendering. The application should consist of a single component, GreetingComponent, which displays a personalized greeting message based on a name input. The component should be able to render correctly both on the client-side (in the browser) and on the server-side (during SSR). The application should include a basic Angular module to house the component. The goal is to demonstrate a functional SSR setup, not to build a complex application.

Key Requirements:

• Server-Side Rendering: The application must be rendered on the server before being sent to the client.
• Client-Side Hydration: The application must be properly hydrated on the client-side, allowing it to become interactive.
• Greeting Component: A GreetingComponent that accepts a name input (string) and displays a greeting message like "Hello, [name]!".
• Basic Angular Module: A module to encapsulate the GreetingComponent.
• Functional SSR Setup: The application should be configured to work with Angular Universal without errors.

Expected Behavior:

1. When the application is initially loaded, the server should render the GreetingComponent with the provided name.
2. The rendered HTML should be sent to the client.
3. Upon client-side hydration, the component should become interactive and any subsequent changes should be handled by Angular.
4. The application should not throw any errors during server-side rendering or client-side hydration.

Edge Cases to Consider:

• Empty Name: Handle the case where the name input is empty or null. Display a default greeting (e.g., "Hello, Guest!").
• Server-Side vs. Client-Side Differences: Ensure that the component behaves consistently on both the server and client. Avoid relying on browser-specific APIs during server-side rendering.

Examples

Example 1:

Input: name = "Alice"
Output: <div class="greeting">Hello, Alice!</div>
Explanation: The GreetingComponent renders the greeting message with the provided name.

Example 2:

Input: name = ""
Output: <div class="greeting">Hello, Guest!</div>
Explanation: The GreetingComponent handles an empty name input and displays a default greeting.

Example 3: (Edge Case - Server-Side Rendering)

Input: name = "Bob" (during server-side rendering)
Output: <div class="greeting">Hello, Bob!</div>
Explanation: The server renders the component with the provided name before sending the HTML to the client.

Constraints

• Angular Version: Use Angular 17 or later.
• TypeScript: The solution must be written in TypeScript.
• Angular Universal: Use the latest stable version of Angular Universal.
• No External Libraries: Avoid using external libraries beyond those typically included with Angular and Angular Universal.
• Simplicity: Focus on demonstrating the core concepts of SSR. Complex features like routing or data fetching are not required.
• Performance: While not a primary focus, avoid unnecessarily complex or inefficient code.

Notes

• You'll need to set up an Angular project with Angular Universal. The Angular CLI can help with this.
• Pay close attention to the AppModule and how it's configured for SSR.
• Debugging SSR can be tricky. Use the browser's developer tools and server logs to identify any issues.
• Consider using ng universal build to generate the server-side application.
• The name input can be hardcoded for simplicity, or passed as a parameter to the component. The focus is on SSR functionality.