api-pagination

# API Pagination Implement scalable pagination strategies for handling large datasets efficiently. ## Pagination Strategies | Strategy | Best For | Performance | |----------|----------|-------------| | Offset/Limit | Small datasets, simple UI | O(n) | | Cursor | Infinite scroll, real-time | O(1) | | Keyset | Large datasets | O(1) | ## Offset Pagination ```javascript app.get('/products', async (req, res) => { const page = parseInt(req.query.page) || 1; const limit = Math.min(parseInt(req.query.limit) || 20, 100); const offset = (page - 1) * limit; const [products, total] = await Promise.all([ Product.find().skip(offset).limit(limit), Product.countDocuments() ]); res.json({ data: products, pagination: { page, limit, total, totalPages: Math.ceil(total / limit) } }); }); ``` ## Cursor Pagination ```javascript app.get('/posts', async (req, res) => { const limit = 20; const cursor = req.query.cursor; const query = cursor ? { _id: { $gt: Buffer.from(cursor, 'base64').toString() } } : {}; const posts = await Post.find(query).limit(limit + 1); const hasMore = posts.length > limit; if (hasMore) posts.pop(); res.json({ data: posts, nextCursor: hasMore ? Buffer.from(posts[posts.length - 1]._id).toString('base64') : null }); }); ``` ## Response Format ```json { "data": [...], "pagination": { "page": 2, "limit": 20, "total": 150, "totalPages": 8 }, "links": { ...