Cheerio Parsing

const cheerio = require('cheerio');const axios = require('axios');
// Load from stringconst $ = cheerio.load('<html><body><h1>Hello</h1></body></html>');
// Load with optionsconst $ = cheerio.load(html, {  xmlMode: false,           // Parse as XML  decodeEntities: true,     // Decode HTML entities  lowerCaseTags: false,     // Keep tag case  lowerCaseAttributeNames: false});
// Fetch and parseasync function fetchAndParse(url) {  const response = await axios.get(url);  return cheerio.load(response.data);}

// By tag$('h1')
// By class$('.article')
// By ID$('#main-content')
// By attribute$('[data-id="123"]')$('a[href^="https://"]')  // Starts with$('a[href$=".pdf"]')      // Ends with$('a[href*="example"]')   // Contains
// Combinations$('div.article > h2')     // Direct child$('div.article h2')       // Any descendant$('h2 + p')               // Adjacent sibling$('h2 ~ p')               // General sibling
// Pseudo-selectors$('li:first-child')$('li:last-child')$('li:nth-child(2)')$('li:nth-child(odd)')$('tr:even')$('input:not([type="hidden"])')$('p:contains("specific text")')

// Select multiple types$('h1, h2, h3')
// Chain selections$('.article').find('.title')

// Get text (includes child text)const text = $('h1').text();
// Get trimmed textconst text = $('h1').text().trim();
// Get HTMLconst html = $('div.content').html();
// Get outer HTMLconst outerHtml = $.html($('div.content'));

// Get attributeconst href = $('a').attr('href');const src = $('img').attr('src');
// Get data attributesconst id = $('div').data('id');  // data-id attribute
// Check if attribute existsconst hasClass = $('div').hasClass('active');

// Iterate with eachconst items = [];$('.product').each((index, element) => {  items.push({    name: $(element).find('.name').text().trim(),    price: $(element).find('.price').text().trim(),    url: $(element).find('a').attr('href')  });});
// Map to arrayconst titles = $('h2').map((i, el) => $(el).text()).get();
// Filter elementsconst featured = $('.product').filter('.featured');
// First/Lastconst first = $('li').first();const last = $('li').last();
// Get by indexconst third = $('li').eq(2);

// Parent$('span').parent()$('span').parents()          // All ancestors$('span').parents('.container')  // Specific ancestor$('span').closest('.wrapper')    // Nearest ancestor matching selector
// Children$('ul').children()           // Direct children$('ul').children('li.active') // Filtered children$('div').contents()          // Including text nodes
// Siblings$('li').siblings()$('li').next()$('li').nextAll()$('li').prev()$('li').prevAll()

// Filter by selector$('li').filter('.active')
// Filter by function$('li').filter((i, el) => $(el).data('price') > 100)
// Find within selection$('.article').find('img')
// Check conditions$('li').is('.active')  // Returns boolean$('li').has('span')    // Has descendant matching selector

function extractTable(tableSelector) {  const $ = this;  const headers = [];  const rows = [];
  // Get headers  $(tableSelector).find('th').each((i, el) => {    headers.push($(el).text().trim());  });
  // Get rows  $(tableSelector).find('tbody tr').each((i, row) => {    const rowData = {};    $(row).find('td').each((j, cell) => {      rowData[headers[j]] = $(cell).text().trim();    });    rows.push(rowData);  });
  return rows;}

function extractList(selector, itemExtractor) {  return $(selector).map((i, el) => itemExtractor($(el))).get();}
// Usageconst products = extractList('.product', ($el) => ({  name: $el.find('.name').text().trim(),  price: parseFloat($el.find('.price').text().replace('$', '')),  image: $el.find('img').attr('src'),  link: $el.find('a').attr('href')}));

function extractPaginationLinks() {  return $('.pagination a')    .map((i, el) => $(el).attr('href'))    .get()    .filter(href => href && !href.includes('#'));}

// Safe extraction with defaultsfunction safeText(selector, defaultValue = '') {  const el = $(selector);  return el.length ? el.text().trim() : defaultValue;}
function safeAttr(selector, attr, defaultValue = null) {  const el = $(selector);  return el.length ? el.attr(attr) : defaultValue;}
// Optional chaining patternconst price = $('.price').first().text()?.trim() || 'N/A';

const { URL } = require('url');
function resolveUrl(baseUrl, relativeUrl) {  if (!relativeUrl) return null;  try {    return new URL(relativeUrl, baseUrl).href;  } catch {    return relativeUrl;  }}
// Usageconst baseUrl = 'https://example.com/products/';$('a').each((i, el) => {  const href = $(el).attr('href');  const absoluteUrl = resolveUrl(baseUrl, href);  console.log(absoluteUrl);});

// Cache selectionsconst $products = $('.product');$products.each((i, el) => {  const $product = $(el);  // Wrap once  // Use $product multiple times});
// Limit parsing scopeconst $article = $('.article');const title = $article.find('.title').text();  // Searches only within article
// Use specific selectors// Good$('div.product > h2.title')// Less efficient$('div').find('.product').find('h2').filter('.title')

const cheerio = require('cheerio');const axios = require('axios');
async function scrapeProducts(url) {  const response = await axios.get(url, {    headers: {      'User-Agent': 'Mozilla/5.0 (compatible; MyScraper/1.0)'    }  });
  const $ = cheerio.load(response.data);  const products = [];
  $('.product-card').each((index, element) => {    const $el = $(element);
    products.push({      name: $el.find('.product-title').text().trim(),      price: parseFloat(        $el.find('.price').text().replace(/[^0-9.]/g, '')      ),      rating: parseFloat($el.find('.rating').attr('data-rating')) || null,      image: $el.find('img').attr('src'),      url: new URL($el.find('a').attr('href'), url).href,      inStock: !$el.find('.out-of-stock').length    });  });
  return products;}
// With error handlingasync function safeScrape(url) {  try {    return await scrapeProducts(url);  } catch (error) {    console.error(`Failed to scrape ${url}:`, error.message);    return [];  }}