![]() ![]() So even if you first learn Selenium in Python it’s very easy to use it in other languages later. In Java, for instance, this is how we switch frames and find elements by id: browser. And so on.Īnother great feature of Selenium is that it’s very similar across all languages it supports. To find an element by its id we use find_element_by_id. We have located the element.Īs the code above shows, Selenium is very intuitive. find_element_by_id ( 'terms' )Īnd that’s it. Once we are on the correct frame we can finally search for the element. The next thing we do is go to that frame. Here it is not, but that is always a possibility and you need to check. Now keep scrolling up to see if “mainFrame” is inside some other frame. ![]() That means our “Search Terms” form is inside a frame named “mainFrame”. To find out, start on that blue-highlighted line we saw before and keep scrolling up until you find HTML pages usually contain multiple “frames” and our element is probably inside one of these frames. We are not ready to locate the element though. Ha! Now we know two attributes of the “Search Terms” form: its name is “terms” and its id is (also) “terms”. Let me copy and paste it below, so you can have a better look at it: The HTML code of the element you selected appears highlighted in blue. For instance, if you do this with the “Search Terms” form on the page we opened above you’ll see something like this: Your browser will then show you the corresponding HTML code. How can we find what these attributes are for a given element? Simple: just right-click it and choose “Inspect Element”. (Don’t worry if you’ve never heard of these things before.) We can use these attributes to help us locate the element we want. This step is going to be easier if you know some HTML but that is not a pre-requisite (you will end up learning some HTML on-the-fly as you do more and more webscraping).Ī page element usually has a few attributes - a name, an id, a CSS selector, an xpath, etc. get ( url )īefore we fill out forms and click buttons we need to locate these elements. Now let’s open the page we want: url = ' sfi=AC00NBGenSrch' browser. When you run this code you’ll see a new instance of Chrome magically launch. Chrome ( executable_path = path_to_chromedriver ) First we start the webdriver: from selenium import webdriver path_to_chromedriver = '/Users/yourname/Desktop/chromedriver' # change path as neededīrowser = webdriver. And adapting it to the new LexisNexis interface will be a nice learning exercise.) It will still help you understand Selenium though. (Obs.: LexisNexis Academic is set to have a new interface starting December 23rd, so if you are in the future the code below may not work. It’s a gated database but you are probably in academia (just a guess) so you should have access to it through your university. In this tutorial we will webscrape LexisNexis Academic. Download the latest version of the chromedriver, unzip it, and note where you saved the unzipped file. For now we will use Chrome (later we will switch to PhantomJS). This driver is browser-specific, so first we need to choose which browser we want to use. You also need a “driver”, which is a small program that allows Selenium to, well, “drive” your browser. To install the Selenium bindings for Python, simply use PIP: pip install selenium All the examples in this tutorial will be in Python, but translating them to those other languages is trivial. ![]() There are Selenium bindings for Python, Java, C#, Ruby, and Javascript. Later posts will cover things like downloading, error handling, dynamic names, and mass webscraping. This first post covers the basics: locating HTML elements and interacting with them. In this tutorial I will show you how to webscrape with Selenium. ![]() That makes it a lot harder for the website to tell your bot from a human being. Hence what the website “sees” is Chrome or Firefox or IE it does not see Python or Selenium. Selenium is a webdriver: it takes control of your browser, which then does all the work. In these cases you may need to disguise your webscraping bot as a human being. These are excellent libraries, but some websites don’t like to be webscraped. If you are webscraping with Python chances are that you have already tried urllib, httplib, requests, etc. ![]()
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