Vue Fallback Rendering: Graceful Component Degradation

In modern web development, it's crucial to handle situations where a component might fail to render due to missing data, network errors, or other unexpected issues. This challenge focuses on implementing robust fallback rendering in Vue.js, ensuring a user-friendly experience even when primary content isn't available. You will create a system that attempts to render a primary component and, if it fails or encounters an error, gracefully displays a fallback component.

Problem Description

Your task is to build a Vue.js component that dynamically renders another component. This "wrapper" component should:

1. Attempt to render a specified "primary" component.
2. If the primary component throws an error during rendering or mounting, or if a specific condition (e.g., missing critical data) is met, it should render a designated "fallback" component instead.
3. The wrapper component should be configurable, allowing developers to easily swap out the primary and fallback components and pass props to them.

Key Requirements:

• Error Handling: Catch rendering errors from the primary component.
• Conditional Fallback: Implement a mechanism to trigger the fallback based on a condition, in addition to catching errors.
• Dynamic Component Loading: Use Vue's Suspense component or onErrorCaptured hook for robust error handling during component rendering.
• Prop Passing: Ensure that props intended for the primary component are correctly passed down to either the primary or the fallback component (as appropriate).
• Reusability: Design the wrapper component to be reusable across different parts of an application.

Expected Behavior:

• When the primary component renders successfully, its content should be displayed.
• When the primary component fails to render (throws an error), the fallback component should be displayed.
• When a predefined condition for fallback is met (e.g., a data prop is null or undefined), the fallback component should be displayed, even if the primary component could technically render.

Edge Cases:

• What happens if the fallback component also fails to render? (Consider this for a more advanced version, but for this challenge, assume the fallback will render).
• How should initial loading states be handled if the primary component involves asynchronous operations?

Examples

Example 1: Successful Rendering

Input:

• WrapperComponent is used with primaryComponent set to UserProfile and fallbackComponent set to DefaultMessage.
• UserProfile is given props: { userId: 123, username: 'Alice' }.
• UserProfile successfully renders, displaying "User: Alice (ID: 123)".

Output:

(The content rendered by UserProfile would appear on the screen, e.g., "User: Alice (ID: 123)")

Example 2: Rendering with an Error

Input:

• WrapperComponent is used with primaryComponent set to ProductDetails and fallbackComponent set to ProductUnavailable.
• ProductDetails is given props: { productId: 456 }.
• Assume ProductDetails intentionally throws an error during its mounted hook (e.g., trying to access a property of undefined).

Output:

(The content rendered by ProductUnavailable would appear on the screen, e.g., "Sorry, product information is currently unavailable.")

Example 3: Rendering with a Conditional Fallback

Input:

• WrapperComponent is used with primaryComponent set to ArticleContent and fallbackComponent set to NoArticleMessage.
• ArticleContent is given props: { articleId: 789, content: null }.
• The WrapperComponent has a condition: if content prop is null or undefined, render fallback.

Output:

(The content rendered by NoArticleMessage would appear on the screen, e.g., "No article content to display.")

Constraints

• The solution must be implemented in TypeScript using Vue 3.
• The wrapper component should accept primaryComponent and fallbackComponent as props, which can be any valid Vue component definition.
• The wrapper component should accept an optional fallbackCondition prop, which is a function that returns a boolean. If this function returns true, the fallback component is rendered.
• All other props passed to the wrapper component should be forwarded to the currently rendering component (either primary or fallback).
• The solution should be efficient and not introduce significant performance overhead.

Notes

• Consider using Vue's built-in Suspense component for handling asynchronous operations and potential errors during data fetching within the primary component.
• The onErrorCaptured hook on the wrapper component can be a powerful tool for catching errors that bubble up from child components.
• Think about how you will pass props dynamically to the components. Vue's v-bind="$attrs" can be useful here.
• For the fallbackCondition, you might pass a function that checks the validity of data props being passed to the primary component.