scraper is a Rust crate for HTML parsing and querying. However, scraper does not natively support XPath queries. Instead, it uses a different querying mechanism called CSS selectors, which is similar to how you would select elements in a style sheet or with JavaScript's document.querySelector() method.
CSS selectors are generally sufficient for many web scraping tasks, but if you specifically need to use XPath queries in Rust, you might want to consider using another library like sxd-document or sxd-xpath. These libraries offer explicit support for XPath expressions.
Here is an example of how to use the scraper crate with CSS selectors:
extern crate scraper;
use scraper::{Html, Selector};
fn main() {
// Some example HTML
let html = r#"
<html>
<body>
<div id="example">
<p>Hello, world!</p>
</div>
</body>
</html>
"#;
// Parse the HTML document
let document = Html::parse_document(html);
// Create a CSS selector to target the paragraph inside the div with id "example"
let selector = Selector::parse("div#example p").unwrap();
// Iterate over elements matching the CSS selector
for element in document.select(&selector) {
// Print the text of each element
println!("{}", element.text().collect::<Vec<_>>().concat());
}
}
If you need to perform XPath queries, you can use the sxd-document and sxd-xpath crates. Here's an example:
extern crate sxd_document;
extern crate sxd_xpath;
use sxd_document::parser;
use sxd_xpath::{Context, Factory};
fn main() {
// Some example HTML (Note: sxd-document is an XML toolkit, so ensure your HTML is XHTML)
let html = r#"
<html>
<body>
<div id="example">
<p>Hello, world!</p>
</div>
</body>
</html>
"#;
// Parse the XHTML document
let package = parser::parse(html).expect("failed to parse XML");
let document = package.as_document();
// XPath factory
let factory = Factory::new();
let xpath = factory.build("/html/body/div[@id='example']/p/text()").expect("could not compile XPath");
// If the XPath is correct
let xpath = xpath.expect("no xpath was compiled");
// Create an empty context
let context = Context::new();
// Evaluate the XPath
let value = xpath.evaluate(&context, document.root()).expect("could not evaluate XPath");
// Check what kind of value we got back
if let sxd_xpath::Value::Nodeset(nodeset) = value {
// If it's a nodeset (list of nodes), iterate over it
for node in nodeset {
// Print the string-value of the node
println!("{}", node.string_value());
}
}
}
Keep in mind that sxd-document and sxd-xpath are more oriented towards XML parsing and querying, so they might not handle some HTML-specific cases as well as dedicated HTML parsing libraries. When working with HTML, ensure that it is well-formed and compatible with XML parsing rules, or consider using an HTML-to-XHTML conversion tool if necessary.
