Hacker News Reel

A lightning-fast, type-safe Hacker News API client with built-in Zod validation—because guessing is overrated. Built for modern TypeScript, Node.js, Deno, and Bun.

🚀 Features

• Type-safe: Zod schemas validate everything at compile time
• Promise-based with optional parallel fetching
• In-memory caching (stale-while-revalidate) to keep your app snappy
• Automatic rate-limiting & retry with exponential backoff
• Recursive comment-tree fetching with configurable depth & concurrency
• Algolia-powered search (front page & full-text)
• Extensible: swap out fetch for any environment
• Bundled Types: Full TS types and schemas exported for your IDE

💾 Installation

npm install hacker-news-reel
# or
yarn add hacker-news-reel
# or
bun add hacker-news-reel

⚡ Quick Start

import { createClient } from 'hacker-news-reel';

const client = createClient({
  retry: { maxRetries: 5, initialBackoff: 500 },
});

// Get top stories
const topIds = await client.getTopStories();
const story = await client.getItemWithComments(topIds[0], { maxDepth: 2 });

console.log(`1. ${story.title} — ${story.url}`);

story.comments.forEach((c, i) => {
  console.log(`${i + 1}. ${c.by}: ${c.text}`);
});

🧰 API Reference

Client Creation

import { createClient } from 'hacker-news-reel';

const client = createClient({
  fetch: myFetchImpl,        // defaults to global fetch
  retry: false | { maxRetries: number; initialBackoff: number },
});

Fetching Stories & Comments

Method	Description
getTopStories()	IDs of top stories
getNewStories()	IDs of newest stories
getBestStories()	IDs of best-ranked stories
getAskStories()	IDs of Ask HN stories
getShowStories()	IDs of Show HN stories
getJobStories()	IDs of job listings
getItem(id)	Fetch a story/comment/job by ID
getItems(ids, concurrency?)	Batch fetch (optional concurrency limit)
getUser(username)	Fetch a user profile
getItemWithComments(id, opts?)	Story + nested comments (maxDepth, concurrency)

Search API

import { createSearchClient } from 'hacker-news-reel';

const search = createSearchClient({
  limiter: { /* Bottleneck options */ },
  fetch: customFetch,
  retry: { maxRetries: 3, initialBackoff: 300 },
});

const results = await search.searchStories('typescript', { hitsPerPage: 10 });
console.log(`Found ${results.nbHits} hits.`);

Error Handling

All rate limits throw a RateLimitError:

import { RateLimitError } from 'hacker-news-reel';

try {
  await client.getNewStories();
} catch (err) {
  if (err instanceof RateLimitError) {
    console.warn(`Rate limited! Retry after ${err.retryAfterSeconds}s.`);
  } else {
    throw err;
  }
}

🛡️ Caching & Rate Limiting

Resource	Fresh (maxAge)	Stale (staleWhileRevalidate)	Max Entries
Items	5 min	1 h	2000
Lists	30 s	2 min	20
Users	5 min	30 min	500
Search	30 s	2 min	500

Uses LRU eviction and Bottleneck to throttle Algolia (~2.7 req/s) in order to make sure we don't run into the 10,000/hour rate limit.

🧠 Advanced Usage

Cache Invalidation

Manually solve one of the hardest problems in computer science.

client.invalidateItemCache(id);
client.clearAllCaches();

Hooks

Add custom hooks for request/response lifecycle:

client.use({
  beforeFetch: (url, opts) => {
    // Add headers, log request, start timer
    console.log(`Fetching: ${url}`);
    const headers = { ...opts?.headers, 'x-custom-header': 'value' };
    return { url, options: { ...opts, headers } };
  },
  afterFetch: (response) => {
    // Record metrics, inspect responses
    console.log(`Response: ${response.status} from ${response.url}`);
    return response;
  },
  onError: (err) => {
    // Handle or transform errors
    console.error(`Error: ${err.message}`);
    // Return a new error to replace the original
    return new Error(`Wrapped: ${err.message}`);
  }
});

📊 API Reference

Zod Schemas

Schema Name	Description
HackerNewsIdSchema	Validates a Hacker News item ID (number, integer, non-negative)
HackerNewsUsernameSchema	Validates a Hacker News username (non-empty string)
HackerNewsIdListSchema	Validates an array of Hacker News item IDs
HackerNewsItemTypeSchema	Validates item types ('job', 'story', 'comment', 'poll', 'pollopt')
HackerNewsItemSchema	Validates complete Hacker News items (stories, comments, etc.)
HackerNewsUserSchema	Validates Hacker News user profiles
HackerNewsUpdatesSchema	Validates the updates endpoint response (changed items and profiles)

TypeScript Types

Type Name	Description
FetchType	Type alias for the Fetch API
FetchParameters	Parameters type for fetch function
RequestInfo	Type for fetch request info (URL or string)
RequestInit	Type for fetch request init options
HackerNewsId	Type alias for a Hacker News item ID (number)
HackerNewsUsername	Type alias for a Hacker News username (string)
HackerNewsIdList	Type alias for an array of Hacker News item IDs
HackerNewsItemType	Union type for item types ('job', 'story', 'comment', 'poll', 'pollopt')
HackerNewsItem	Interface for Hacker News items (stories, comments, etc.)
HackerNewsCommentTree	Extended HackerNewsItem with nested replies for comment trees
HackerNewsUser	Interface for Hacker News user profiles
HackerNewsUpdates	Interface for updates endpoint response