unprint
unprint is a web scraping utility built around JSDOM, providing convenience methods for quickly extracting common data types.
Install
npm install unprint
Usage
const unprint = require('unprint');
Global options
unprint.options({
headers: {
'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36'
},
})
Querying
For optimal flexibility, unprint query methods can be used with or without initialization. If you already have access to DOM elements using another library or unprint instance, you can query it by using the uninitialized query methods provided directly from the library, and passing the element as the first argument, as such:
unprint.query.element(element, 'h1#title') // HTMLHeadingElement
Both unprint.get() and unprint.init() return its query methods pre-initialized, removing the element argument in favor of the element retrieved or received. Initialized query methods therefore will not accept a custom element, usually expecting the selector as the first argument instead.
const result = await unprint.get('http://localhot:3101/html');
const { query } = result.context;
query.element('h1#title'); // HTMLHeadingElementconst result = await fetch('http://localhot:3101/html');
const body = await res.text();
const { query } = await unprint.init(body);
query.element('h1#title'); // HTMLHeadingElementFrom here on, the query methods will be described in their initialized form. The API for the uninitialized methods is identical, except for the element passed as the first argument
Selector
The selector can be a CSS selector, an XPath selector starting with /, or an array of either or both acting as fallbacks. If the selector is falsy, the input element will be used.
Querying multiple elements
Most methods can be used in plural, returning an array of results, i.e. query.elements(), query.dates().
Query an element
query.element([selector], [options])
Returns the element node directly.
Query an attribute
query.attribute(selector, attribute, [options]) or query.attr()
Return the contents of an attribute. Alias for query.element([selector], { attribute: [attribute] }).
Query existence
query.exists(selector, [options])
Return the presence of an element as a boolean.
Query count
query.count(selector, [options])
Return the number of elements that match the selector.
Query the content
query.content([selector], [options])
Return the text contents of an element (.textContent).
Query a number
query.number([selector], [options])
Options
-
match: The regular expression to use to extract a number from text, default/\d+(\.\d+)?/for decimal numbers. -
matchIndex: The index of the match result, useful for expressions containing groups or a global flag, default0. -
separator: Whether to use.(Europe) or,(US) as the decimal separator, default.
Return the contents of the element or attribute as a Number primitive.
Query the HTML
query.content([selector], [options])
Return the HTML contents of an element (.innerHTML).
Query the text
query.text([selector], [options])
Return the text contents of an element, skipping non-text children, as opposed to querying content.
Options
-
join: Join text nodes into one string -
trim: Remove excess whitespace -
filter: Remove empty text nodes
Query a URL
query.url([selector], [options])
Options
-
origin: The hostname to prefix when it is not included in the URL (/path). -
protocol: The protocol to use when it is not included in the URL (:www.example.com, defaulthttp).
Returns the href from an anchor element (or any other specified target) as a string.
Query an image
query.image([selector], [options]) or query.img()
Options:
- All options supported by
query.url().
Returns the src from an image element (or any other specified target) as a string.
Query a dataset
query.dataset(selector, property, [options]) or query.data()
Return the contents of a data- attribute.
Query a source set
query.sourceSet([selector], [options]) or query.srcSet()
Options:
-
includeDescriptor: Produce an array of{ descriptor, url }instead of URL strings. - All options supported by
query.url().
Returns an array of media URLs from the srcset of an media element as strings sorted by their descriptor from large to small.
Query a video
query.video([selector], [options])
Options:
- All options supported by
query.url().
Returns the src from an video source element (or any other specified target) as a string.
Query a date
query.date(selector, format, [options])
Arguments
-
format(string, array): The input format as a string or array of strings described by the Moment.js docs.
Options
-
match(RegExp): The text to extract before attempting to parse it as a date. The default expression will attempt to extract any of 01-01-1970, 1970-01-01, 01/01/1970 or January 1, 1970 with optional 00:00[:00] time. -
matchIndex: The index of the match result, useful for expressions containing groups or a global flag, default0. -
timezone(string): The name of the input timezone, defaults to 'UTC'.
Returns a Date object.
Query a duration
query.duration(selector, format, [options]) or query.dur
Options
-
match(RegExp): The text to extract before attempting to parse it as a duration. The default expression will attempt to extract(hh:)mm:ssandPT##H##M##S.
Returns the duration in seconds as a number.
Query JSON
query.json([selector], [options])
Returns the parsed JSON content of an element as an object.
HTTP request
unprint.get(url, [options])unprint.post(url, body, [options])
Options
-
select: Pre-query and initialize a specific element on the page -
selectAll: Pre-query and initialize multiple specific element on the page
Returns
{
context: { // using select or no option
query, // (object) unprint querying methods
},
context: [{ // using selectAll
query,
}],
html, // (string) HTML body
data, // (object) parsed JSON response
status, // (number) HTTP status code
ok, // (boolean) status code >= 200 and < 300
response, // (object) the original axios response object, alias 'res'
res, // (object) alias for 'response'
}