- #Building a webscraper that saves to a rails app how to#
- #Building a webscraper that saves to a rails app install#
We added the data to our data_arr array.CSS selectors are truly elegant, aren't they? 🤩 Once Nokogiri had the DOM, we politely asked it for the description and the picture URL.We used OpenURI to load the content of the URL and provided it to Nokogiri.We imported the libraries we are going to use.So, what were we doing here? Let's quickly recap. Once we have our URI, we can pass it to get_response, which will provide us with a Net::HTTPResponse object and whose body method will provide us with the HTML document. In order to make a request to Douglas Adams' Wikipedia page easily, we first need to convert our URL string into a URI object, using the open-uri gem. Ruby's standard library comes with an HTTP client of its own, namely, the net-http gem. You can use whichever of the below clients you like the most and it will work with the step 2. Let's take a look at our three main options: net/http, open-uri, and HTTParty. In order to send a request to any website or web app, you would need to use an HTTP client. You would for sure start with getting data from Wikipedia. Imagine you want to build the ultimate Douglas Adams fan wiki.
#Building a webscraper that saves to a rails app how to#
In this section, we will cover how to scrape a Wikipedia page with Ruby. As for Ruby, we are using version 3 for our examples and our main playground will be the file scraper.rb. Moreover, we will use open-uri, net/http, and csv, which are part of the standard Ruby library so there's no need for a separate installation.
#Building a webscraper that saves to a rails app install#
In order to be able to code along with this part, you may need to install the following gems: While we won't be able to cover all the use cases of these tools, we will provide good grounds for you to get started and explore more on your own. While there is a multitude of gems, we will focus on the most popular ones and use their Github metrics (use, stars, and forks) as indicators. Note: This article does assume that the reader is familiar with the Ruby platform. We will have a closer look on how to address this, using web scraping frameworks, in the second part of this article. Particularly in the context of single-page applications, we will quickly come across major obstacles due to their heavy use of JavaScript. This approach to web scraping does have its limitations, however, and can come with a fair dose of frustration. We start with an introduction to building a web scraper using common Ruby HTTP clients and how to parse HTML documents in Ruby. This post covers the main tools and techniques for web scraping in Ruby.
0 kommentar(er)
