SwiftSoup is a pure Swift library for working with real-world HTML. It provides a convenient API for extracting and manipulating data, using the best of DOM, CSS, and jquery-like methods. SwiftSoup is a Swift port of the popular Java HTML parser, Jsoup.
The library is designed to handle all sorts of HTML found in the wild, from pristine and semantic to invalid and "tag soup" HTML. SwiftSoup allows you to parse HTML documents, access a variety of elements, attributes, and text, as well as manipulate the HTML elements.
Uses of SwiftSoup:
Data Extraction: SwiftSoup can be used to scrape and parse data from HTML pages. This is useful for extracting information from websites that do not have an API.
HTML Cleaning: SwiftSoup can clean up and sanitize HTML content by removing unwanted tags and attributes, making it safe for displaying in web or mobile applications.
Web Crawling: Although SwiftSoup is just a parser, it can be used in conjunction with HTTP networking libraries to create web crawlers that navigate and process content from multiple pages or sites.
Offline HTML Processing: You can use SwiftSoup to manipulate and extract data from HTML documents stored locally on your device.
Testing: SwiftSoup can be used for unit testing by providing HTML content to test the functionality of HTML-based applications.
Basic Example of SwiftSoup:
Here’s an example of how SwiftSoup can be used in a Swift program to parse an HTML string and extract data:
import SwiftSoup
let htmlString = """
<html>
<head>
<title>Sample Page</title>
</head>
<body>
<p class="description">This is a sample website</p>
<a href="http://example.com">Visit Site</a>
</body>
</html>
"""
do {
// Parse the HTML string
let doc: Document = try SwiftSoup.parse(htmlString)
// Get the title of the document
let title: String = try doc.title()
print(title) // Output: Sample Page
// Get the text of the class "description"
let description: Element? = try doc.select("p.description").first()
if let descriptionText = description?.text() {
print(descriptionText) // Output: This is a sample website
}
// Get the href attribute of the link
let link: Element? = try doc.select("a").first()
if let linkHref = try link?.attr("href") {
print(linkHref) // Output: http://example.com
}
} catch Exception.Error(let type, let message) {
print(message)
} catch {
print("error")
}
Installation:
To include SwiftSoup in your project, you can use Swift Package Manager (SPM), CocoaPods, or Carthage. For example, with CocoaPods you would add the following line to your Podfile:
pod 'SwiftSoup'
Then run pod install to install the dependency.
With Swift Package Manager, you would add a dependency to your Package.swift file:
dependencies: [
.package(url: "https://github.com/scinfu/SwiftSoup.git", from: "2.3.2")
]
Notes:
SwiftSoup is typically used in server-side Swift applications or macOS command-line tools. It's also suitable for use in iOS apps where parsing or manipulating HTML content is necessary. While SwiftSoup is powerful, remember that web scraping must be done responsibly and ethically, respecting the terms of service and robots.txt files of the websites being scraped.
