The Content-Type HTTP header of the web page is parsed using theĪnd the result is stored in the ntentType object. Text/html, application/xhtml+xml, application/xml Thus the context parameter of the Page function will have different values: Content types The web pages with various content types are parsed differently and HTTP header setting in the requests from the scraper,Įither in Start URLs, Pseudo URLs or in the Prepare request function. Types, and you're still receiving invalid responses, be sure to override the Accept HTML and XML are preferred over JSON and other types. Note that while the default Accept HTTP header will allow any content type to be received, Use the Additional MIME types ( additionalMimeTypes) input option. If you want the crawler to process other content types, Content typesīy default, Cheerio Scraper only processes web pages with the text/html, application/json, application/xml, application/xhtml+xml MIME content types (as reported by the Content-Type HTTP header),Īnd skips pages with other content types. If you'd like to learn more about the inner workings of the scraper, see the respective documentation. Under the hood, Cheerio Scraper is built using the CheerioCrawler classįrom Crawlee. If there are more items in the queue, repeats step 2, otherwise finishes.Ĭheerio Scraper has a number of advanced configuration settings to improve performance, set cookies for login to websites, limit the number of records, etc.If a link matches any of the Glob Patterns and/or Pseudo-URLs and has not yet been visited, adds it to the queue. Optionally, finds all links from the page using the Link selector.Executes the Page function on the loaded page and saves its results.Fetches the first URL from the queue and constructs a DOM from the fetched HTML string. ![]() Adds each Start URL to the crawling queue.In summary, Cheerio Scraper works as follows: Since the scraper does not use the full web browser, writing the Page function is equivalent to writing server-side Node.js code - it uses the server-side library Cheerio. This is JavaScript code that is executed for every web page loaded. To tell the scraper how to extract data from web pages, you need to provide a Page function. This is useful for the recursive crawling of entire websites, e.g. You can make the scraper follow page links on the fly by setting a Link selector, Glob Patterns and/or Pseudo-URLs to tell the scraper which links it should add to the crawling queue. The scraper starts by loading the pages specified in the Start URLs field. Second, tell it how to extract data from each page. To get started with Cheerio Scraper, you only need two things. You might prefer to start with Scraping with Web Scraper tutorial from the Apify documentation and then continue with Scraping with Cheerio Scraper, a tutorial which will walk you through all the steps and provide a number of examples. If you're unfamiliar with web scraping or web development in general, ![]() It then provides the user an API to work with that DOM.Ĭheerio Scraper is ideal for scraping web pages that do not rely on client-side JavaScript to serve their content and can be up to 20 times faster than using a full-browser solution such as Puppeteer. ![]() It does not require aīrowser but instead constructs a DOM from an HTML string. Fast.Ĭheerio is a server-side version of the popular jQuery library. It retrieves the HTML pages, parses them using the Cheerio Node.js library and lets you extract any data from them. Cheerio Scraper is a ready-made solution for crawling websites using plain HTTP requests.
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