![]() ![]() In this demonstration, we are going to use Puppeteer and Node.js to build our web scraping tool. And web scraping is the only solution when websites do not provide an API and data is needed. It makes sense why everyone needs web scraping because it makes manual- data gathering processes very fast. We have gone over different web scraping tools by using programming languages and without programming like selenium, request, BeautifulSoup, MechanicalSoup, Parsehub, Diffbot, etc. Basic web scraping script consists of a “crawler” that goes to the internet, surf around the web, and scrape information from given pages. log( "CHILD: url received from parent process", url) Ĭonst browser = await puppeteer.Web scraping is the process of extracting information from the internet, now the intention behind this can be research, education, business, analysis, and others. The code snippet below is a simple example of running parallel downloads with Puppeteer.Ĭonst downloadPath = path. □ If you are not familiar with how child process work in Node I highly encourage you to give this article a read. ![]() We can combine the child process module with our Puppeteer script and download files in parallel. Child process is how Node.js handles parallel programming. ![]() We can fork multiple child_proces in Node. Our CPU cores can run multiple processes at the same time. □ Learn more about the single threaded architecture of node here Therefore if we have to download 10 files each 1 gigabyte in size and each requiring about 3 mins to download then with a single process we will have to wait for 10 x 3 = 30 minutes for the task to finish. It can only execute one process at a time. You see Node.js in its core is a single-threaded system. However, if you have to download multiple large files things start to get complicated. In this next part, we will dive deep into some of the advanced concepts. ![]()
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