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Start by clarifying the requirements: what fields are in the JSON, how errors should be handled, and whether the rendering needs to be dynamic or static. Then outline a clean, modular solution: fetch the JSON, parse it, and render posts using safe DOM manipulation, while discussing trade-offs like performance and security. Finally, mention how you would test and extend the solution.
Pro tip: Show awareness of XSS risks by using textContent instead of innerHTML for user-generated content, and mention that in a real app you'd fetch from an API with error handling and loading states.
Ask about the JSON structure, expected number of posts, browser support, and whether the file is static or fetched. This shows you think before coding.
Describe fetching the JSON file (using fetch or import), parsing it, and validating the data. Mention error handling for network or parse failures.
Explain how you'll create DOM elements for each post, set text content safely, and append to a container. Discuss using a DocumentFragment for performance.
Talk about XSS prevention, handling missing fields, empty states, and whether to render all at once or paginate. Mention accessibility considerations.
Mention unit tests for parsing and rendering, and how the solution could be extended to fetch from an API or add features like sorting.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
I forgot to clear the form on the first pass.
Start by clarifying the requirements and constraints, then outline a clean component-based solution using controlled inputs and state management. Emphasize the importance of optimistic UI updates, error handling, and accessibility. Finally, discuss trade-offs between client-side and server-side rendering, and how to integrate with the existing API.
Pro tip: Mention that you would debounce or disable the submit button to prevent duplicate submissions, and that you would validate the input both client-side and server-side for security.
Ask about the tech stack (e.g., React, Vue), existing state management, and API endpoints. Confirm whether the post should be persisted to a backend or just added locally.
Outline a form component with controlled inputs for title and body, and a parent component that manages the list of posts. Use state to hold form values and the list.
On submit, prevent default, validate inputs, create a new post object, and update the list state. Optionally send a POST request to the server and handle the response.
Clear the form after submission, disable the submit button during processing, show loading/error states, and ensure accessibility (labels, ARIA).
Talk about optimistic vs pessimistic UI updates, client-side vs server-side validation, and how to avoid memory leaks or race conditions.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Start by outlining the data flow: fetch posts, then concurrently fetch authors and the current user, using Promise.all for parallelism. Emphasize robust error handling per author fetch and loading states, and discuss trade-offs like waterfall vs. parallel requests and caching.
Pro tip: Mention that you'd use Promise.allSettled for author fetches to ensure one failure doesn't break the entire UI, and consider caching author data to avoid redundant requests.
Initiate fetching the list of posts and the current logged-in user simultaneously, as these are independent requests. Handle loading and error states for these initial fetches.
For each post, fetch its author concurrently using Promise.all or Promise.allSettled. This avoids sequential waterfalls and improves performance.
If an author fetch fails, fallback to 'Unknown author' for that post. Use Promise.allSettled to capture both fulfilled and rejected promises without failing the entire batch.
Compare each post's author ID with the current user's ID. If they match, display 'You' instead of the author's name.
Show loading indicators while any fetch is in progress. If the posts or current user fetch fails, show an error message with a retry option. For author fetches, handle errors per post as described.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Start by clarifying requirements and constraints, then propose a solution that optimizes for immediate UI feedback while handling re-sorting efficiently. Discuss trade-offs between different data structures and algorithms, and consider edge cases like rapid clicks and large datasets.
Pro tip: Mention that you would debounce or batch UI updates to avoid excessive re-renders, and consider optimistic UI updates with server reconciliation for a smooth user experience.
Ask about the expected scale (number of posts, frequency of likes), whether the like count is persisted to a backend, and if real-time updates from other users are needed.
Select a data structure that allows efficient increment and re-sort, such as a max-heap or a balanced tree, or simply maintain a sorted list and use insertion sort after each increment.
Decide between immediate local state update and server round-trip; consider optimistic UI updates and debouncing to prevent flickering and excessive re-renders.
After incrementing the like count, re-sort the list by likes descending; if using a sorted structure, adjust the position of the liked post instead of sorting the entire list.
Handle rapid clicks, concurrent updates, and large lists; discuss trade-offs between client-side and server-side sorting, and potential use of virtual scrolling.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.