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Scrapling/docs/parsing/main_classes.md
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Karim shoair ed694f0a79 First version of Scrapling full documentation
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## Introduction
After exploring the various ways to select elements with Scrapling and related features, Let's take a step back and examine the [Adaptor](#adaptor) class generally and other objects to better understand the parsing engine.
The [Adaptor](#adaptor) class is the core parsing engine in Scrapling that provides HTML parsing and element selection capabilities. You can always import it with any of the following imports
```python
from scrapling import Adaptor
from scrapling.parser import Adaptor
```
then use it directly as you already learned in the [overview](../overview.md) page
```python
adaptor = Adaptor(
text='<html>...</html>',
url='https://example.com'
)
# Then select elements as you like
elements = adaptor.css('.product')
```
In Scrapling, the main object you deal with after passing an HTML source or fetching a website is, of course, an [Adaptor](#adaptor) object. Any operation you do, like selection, navigation, etc., will return either an [Adaptor](#adaptor) object or an [Adaptors](#adaptors) object, given that the result is element/elements from the page, not text or similar.
In other words, the main page is a [Adaptor](#adaptor) object, and the elements within are [Adaptor](#adaptor) objects, and so on. Any text, such as the text content inside elements or the text inside element attributes, is a [TextHandler](#texthandler) object, and the attributes of each element are stored as [AttributesHandler](#attributeshandler). We will return to both objects later, so let's focus on the [Adaptor](#adaptor) object.
## Adaptor
### Arguments explained
The most important ones are `text` and `body`. Both are used to pass the HTML code you want to parse, but the first one accepts `str`, and the latter accepts `bytes` like how you used to do with `parsel` :)
Otherwise, you have the arguments `url`, `auto_match`, `storage`, and `storage_args`. All these arguments are settings used with the `auto_match` feature, and they don't make a difference if you are not going to use that feature, so just ignore them for now, and we will explain them in the [automatch](automatch.md) feature page.
Then you have the arguments for adjustments for parsing or adjusting/manipulating the HTML while the library parsing it:
- **encoding**: This is the encoding that will be used while parsing the HTML. The default is `UTF-8`.
- **keep_comments**: This tells the library whether to keep HTML comments while parsing the page. It's disabled by default, as it can mess up your scraping in many ways.
- **keep_cdata**: Same logic as the HTML comments. [cdata](https://stackoverflow.com/questions/7092236/what-is-cdata-in-html) is removed by default for cleaner HTML. This also means when you check for the raw html content, you will find it doesn't have the cdata.
I have intended to ignore the arguments `huge_tree` and `root` to avoid making this page more complicated than needed.
You may notice that I'm doing that a lot, and that's because it's something you don't need to know to use the library. The development section will cover these missing parts if you are that interested.
After that, for the main page and elements within, most properties don't get initialized until you use it like the text content of a page/element, and this is one of the reasons for Scrapling speed :)
### Properties
You have already seen much of this on the [overview](../overview.md) page, but don't worry if you didn't. We will review it more thoroughly using more advanced methods/usages. For clarity, the properties for traversal are separated below in the [traversal](#traversal) section.
Let's say we are parsing this HTML page for simplicity:
```html
<html>
<head>
<title>Some page</title>
</head>
<body>
<div class="product-list">
<article class="product" data-id="1">
<h3>Product 1</h3>
<p class="description">This is product 1</p>
<span class="price">$10.99</span>
<div class="hidden stock">In stock: 5</div>
</article>
<article class="product" data-id="2">
<h3>Product 2</h3>
<p class="description">This is product 2</p>
<span class="price">$20.99</span>
<div class="hidden stock">In stock: 3</div>
</article>
<article class="product" data-id="3">
<h3>Product 3</h3>
<p class="description">This is product 3</p>
<span class="price">$15.99</span>
<div class="hidden stock">Out of stock</div>
</article>
</div>
<script id="page-data" type="application/json">
{
"lastUpdated": "2024-09-22T10:30:00Z",
"totalProducts": 3
}
</script>
</body>
</html>
```
Load the page directly as shown before:
```python
from scrapling import Adaptor
page = Adaptor(html_doc)
```
Get all text content on the page recursively
```python
>>> page.get_all_text()
'Some page\n\n \n\n \nProduct 1\nThis is product 1\n$10.99\nIn stock: 5\nProduct 2\nThis is product 2\n$20.99\nIn stock: 3\nProduct 3\nThis is product 3\n$15.99\nOut of stock'
```
Get the first article as explained before; we will use it as an example
```python
article = page.find('article')
```
With the same logic, get all text content on the element recursively
```python
>>> article.get_all_text()
'Product 1\nThis is product 1\n$10.99\nIn stock: 5'
```
But if you try to get the direct text content, it will be empty; notice the logic difference
```python
>>> article.text
''
```
The `get_all_text` method has the following optional arguments:
1. **separator**: All strings collected will be concatenated using this separator. The default is '\n'
2. **strip**: If enabled, strings will be stripped before concatenation. Disabled by default.
3. **ignore_tags**: A tuple of all tag names you want to ignore in the final results. The default is `('script', 'style',)`.
4. **valid_values**: If enabled, the method will only collect elements with real values, so all elements with empty text content or only whitespaces will be ignored. It's enabled by default
By the way, the text returned here is not a standard string but a [TextHandler](#texthandler); we will get to this in detail later, so if the text content can be serialized to JSON, then use `.json()` on it
```python
>>> script = page.find('script')
>>> script.json()
{'lastUpdated': '2024-09-22T10:30:00Z', 'totalProducts': 3}
```
Let's continue to get the element tag
```python
>>> article.tag
'article'
```
If you used it on the page directly, you will find you are operating on the root `html` element
```python
>>> page.tag
'html'
```
Now, I think I hammered the (`page`/`element`) idea, so I won't return to it again.
Getting the attributes of the element
```python
>>> print(article.attrib)
{'class': 'product', 'data-id': '1'}
```
Get the HTML content of the element
```python
>>> article.html_content
'<article class="product" data-id="1"><h3>Product 1</h3>\n <p class="description">This is product 1</p>\n <span class="price">$10.99</span>\n <div class="hidden stock">In stock: 5</div>\n </article>'
```
It's the same if you used the `.body` property
```python
>>> article.body
'<article class="product" data-id="1"><h3>Product 1</h3>\n <p class="description">This is product 1</p>\n <span class="price">$10.99</span>\n <div class="hidden stock">In stock: 5</div>\n </article>'
```
Get the prettified version of the HTML content of the element
```python
>>> print(article.prettify())
<article class="product" data-id="1"><h3>Product 1</h3>
<p class="description">This is product 1</p>
<span class="price">$10.99</span>
<div class="hidden stock">In stock: 5</div>
</article>
```
To get all the ancestors in the DOM tree of this element
```python
>>> article.path
[<data='<div class="product-list"> <article clas...' parent='<body> <div class="product-list"> <artic...'>,
<data='<body> <div class="product-list"> <artic...' parent='<html><head><title>Some page</title></he...'>,
<data='<html><head><title>Some page</title></he...'>]
```
Generate a CSS shortened selector if possible, or generate the full selector
```python
>>> article.generate_css_selector
'body > div > article'
>>> article.generate_full_css_selector
'body > div > article'
```
Same case with XPath
```python
>>> article.generate_xpath_selector
"//body/div/article"
>>> article.generate_full_xpath_selector
"//body/div/article"
```
### Traversal
Using the elements we found above, we will go over the properties/methods for moving in the page in detail.
If you are unfamiliar with the DOM tree or the tree data structure in general, the following traversal part can be confusing. I recommend you look up these concepts online for a better understanding.
If you are too lazy to search about it, here's a quick explanation to give you a good idea.<br/>
Simply put, the `html` element is the root of the website's tree, as every page starts with an `html` element.<br/>
This element will be directly above elements like `head` and `body`. These are considered "children" of the `html` element, and the `html` element is considered their "parent." The element `body` is a "sibling" of the element `head` and vice versa.
Accessing the parent of an element
```python
>>> article.parent
<data='<div class="product-list"> <article clas...' parent='<body> <div class="product-list"> <artic...'>
>>> article.parent.tag
'div'
```
You can chain it as you want, which applies to all similar properties/methods we will review.
```python
>>> article.parent.parent.tag
'body'
```
Get the children of an element
```python
>>> article.children
[<data='<h3>Product 1</h3>' parent='<article class="product" data-id="1"><h3...'>,
<data='<p class="description">This is product 1...' parent='<article class="product" data-id="1"><h3...'>,
<data='<span class="price">$10.99</span>' parent='<article class="product" data-id="1"><h3...'>,
<data='<div class="hidden stock">In stock: 5</d...' parent='<article class="product" data-id="1"><h3...'>]
```
Get all elements underneath an element. It acts as a nested version of the `children` property
```python
>>> article.below_elements
[<data='<h3>Product 1</h3>' parent='<article class="product" data-id="1"><h3...'>,
<data='<p class="description">This is product 1...' parent='<article class="product" data-id="1"><h3...'>,
<data='<span class="price">$10.99</span>' parent='<article class="product" data-id="1"><h3...'>,
<data='<div class="hidden stock">In stock: 5</d...' parent='<article class="product" data-id="1"><h3...'>]
```
This element returns the same result as the `children` property because its children don't have children.
Another example of using the element with the `product-list` class will clear the difference between the `children` property and the `below_elements` property
```python
>>> products_list = page.css_first('.product-list')
>>> products_list.children
[<data='<article class="product" data-id="1"><h3...' parent='<div class="product-list"> <article clas...'>,
<data='<article class="product" data-id="2"><h3...' parent='<div class="product-list"> <article clas...'>,
<data='<article class="product" data-id="3"><h3...' parent='<div class="product-list"> <article clas...'>]
>>> products_list.below_elements
[<data='<article class="product" data-id="1"><h3...' parent='<div class="product-list"> <article clas...'>,
<data='<h3>Product 1</h3>' parent='<article class="product" data-id="1"><h3...'>,
<data='<p class="description">This is product 1...' parent='<article class="product" data-id="1"><h3...'>,
<data='<span class="price">$10.99</span>' parent='<article class="product" data-id="1"><h3...'>,
<data='<div class="hidden stock">In stock: 5</d...' parent='<article class="product" data-id="1"><h3...'>,
<data='<article class="product" data-id="2"><h3...' parent='<div class="product-list"> <article clas...'>,
...]
```
Get the siblings of an element
```python
>>> article.siblings
[<data='<article class="product" data-id="2"><h3...' parent='<div class="product-list"> <article clas...'>,
<data='<article class="product" data-id="3"><h3...' parent='<div class="product-list"> <article clas...'>]
```
Get the next element of the current element
```python
>>> article.next # gets the next element, the same logic applies to `quote.previous`
<data='<article class="product" data-id="2"><h3...' parent='<div class="product-list"> <article clas...'>
```
The same logic applies to the `previous` property
```python
>>> article.previous # It's the first child, so it doesn't have a previous element
>>> second_article = page.css_first('.product[data-id="2"]')
>>> second_article.previous
<data='<article class="product" data-id="1"><h3...' parent='<div class="product-list"> <article clas...'>
```
You can check easily and pretty fast if an element has a specific class name or not
```python
>>> article.has_class('product')
True
```
If your case needs more than the element's parent, you can iterate over the whole ancestors' tree of any element, like the example below
```python
for ancestor in article.iterancestors():
# do something with it...
```
You can search for a specific ancestor of an element that satisfies a function; all you need to do is to pass a function that takes an [Adaptor](#adaptor) object as an argument and return `True` if the condition satisfies or `False` otherwise like below:
```python
>>> article.find_ancestor(lambda ancestor: ancestor.has_class('product-list'))
<data='<div class="product-list"> <article clas...' parent='<body> <div class="product-list"> <artic...'>
>>> article.find_ancestor(lambda ancestor: ancestor.css('.product-list')) # Same result, different approach
<data='<div class="product-list"> <article clas...' parent='<body> <div class="product-list"> <artic...'>
```
## Adaptors
The class `Adaptors` is the "List" version of the [Adaptor](#adaptor) class. It inherits from the Python standard `List` type, so it shares all `List` properties and methods while adding more methods to make the operations you want to execute on the [Adaptor](#adaptor) instances within more straightforward.
In the [Adaptor](#adaptor) class, all methods/properties that should return a group of elements return them as an [Adaptors](#adaptors) class instance. The only exceptions are when you use the CSS/XPath methods as follows:
- If you selected a text node with the selector, then the return type will be [TextHandler](#texthandler)/[TextHandlers](#texthandlers). <br/>Examples:
```python
>>> page.css('a::text') # -> TextHandlers
>>> page.xpath('//a/text()') # -> TextHandlers
>>> page.css_first('a::text') # -> TextHandler
>>> page.xpath_first('//a/text()') # -> TextHandler
>>> page.css('a::attr(href)') # -> TextHandlers
>>> page.xpath('//a/@href') # -> TextHandlers
>>> page.css_first('a::attr(href)') # -> TextHandler
>>> page.xpath_first('//a/@href') # -> TextHandler
```
- If you used a combined selector that returns mixed types, the result will be a Python standard `List`. <br/>Examples:
```python
>>> page.css('.price_color') # -> Adaptors
>>> page.css('.product_pod a::attr(href)') # -> TextHandlers
>>> page.css('.price_color, .product_pod a::attr(href)') # -> List
```
Let's see what [Adaptors](#adaptors) class adds to the table with that out of the way.
### Properties
Apart from the normal operations on Python lists like iteration, slicing, etc...
You can do the following:
Execute CSS and XPath selectors directly on the [Adaptor](#adaptor) instances it has while the arguments and the return types are the same as [Adaptor](#adaptor)'s `css` and `xpath` methods. This, of course, makes chaining methods very straightforward.
```python
>>> page.css('.product_pod a')
[<data='<a href="catalogue/a-light-in-the-attic_...' parent='<div class="image_container"> <a href="c...'>,
<data='<a href="catalogue/a-light-in-the-attic_...' parent='<h3><a href="catalogue/a-light-in-the-at...'>,
<data='<a href="catalogue/tipping-the-velvet_99...' parent='<div class="image_container"> <a href="c...'>,
<data='<a href="catalogue/tipping-the-velvet_99...' parent='<h3><a href="catalogue/tipping-the-velve...'>,
<data='<a href="catalogue/soumission_998/index....' parent='<div class="image_container"> <a href="c...'>,
<data='<a href="catalogue/soumission_998/index....' parent='<h3><a href="catalogue/soumission_998/in...'>,
...]
>>> page.css('.product_pod').css('a') # Returns the same result
[<data='<a href="catalogue/a-light-in-the-attic_...' parent='<div class="image_container"> <a href="c...'>,
<data='<a href="catalogue/a-light-in-the-attic_...' parent='<h3><a href="catalogue/a-light-in-the-at...'>,
<data='<a href="catalogue/tipping-the-velvet_99...' parent='<div class="image_container"> <a href="c...'>,
<data='<a href="catalogue/tipping-the-velvet_99...' parent='<h3><a href="catalogue/tipping-the-velve...'>,
<data='<a href="catalogue/soumission_998/index....' parent='<div class="image_container"> <a href="c...'>,
<data='<a href="catalogue/soumission_998/index....' parent='<h3><a href="catalogue/soumission_998/in...'>,
...]
```
Run the `re` and `re_first` methods directly. They take the same arguments passed as the [Adaptor](#adaptor) class. I'm still leaving these methods to be explained in the [TextHandler](#texthandler) section below.
However, in this class, the `re_first` behaves differently as it runs `re` on each [Adaptor](#adaptor) within and returns the first one with a result. The `re` method will return a [TextHandlers](#texthandlers) object as normal that has all the results combined in one [TextHandlers](#texthandlers) instance.
```python
>>> page.css('.price_color').re(r'[\d\.]+')
['51.77',
'53.74',
'50.10',
'47.82',
'54.23',
...]
>>> page.css('.product_pod h3 a::attr(href)').re(r'catalogue/(.*)/index.html')
['a-light-in-the-attic_1000',
'tipping-the-velvet_999',
'soumission_998',
'sharp-objects_997',
...]
```
With the `search` method, you can search quickly in the available [Adaptor](#adaptor) classes. The function you pass must accept an [Adaptor](#adaptor) instance as the first argument and return True/False. The method will return the first [Adaptor](#adaptor) instance that satisfies the function; otherwise, it will return `None`.
```python
# Find all the products with price '53.23'
>>> search_function = lambda p: float(p.css('.price_color').re_first(r'[\d\.]+')) == 54.23
>>> page.css('.product_pod').search(search_function)
<data='<article class="product_pod"><div class=...' parent='<li class="col-xs-6 col-sm-4 col-md-3 co...'>
```
You can use the `filter` method, too, which takes a function like the `search` method but returns an `Adaptors` instance of all the [Adaptor](#adaptor) classes that satisfy the function
```python
# Find all products with prices over $50
>>> filtering_function = lambda p: float(p.css('.price_color').re_first(r'[\d\.]+')) > 50
>>> page.css('.product_pod').filter(filtering_function)
[<data='<article class="product_pod"><div class=...' parent='<li class="col-xs-6 col-sm-4 col-md-3 co...'>,
<data='<article class="product_pod"><div class=...' parent='<li class="col-xs-6 col-sm-4 col-md-3 co...'>,
<data='<article class="product_pod"><div class=...' parent='<li class="col-xs-6 col-sm-4 col-md-3 co...'>,
...]
```
## TextHandler
This class is mandatory to understand, as all methods/properties that should return a string for you will return `TextHandler`, and the ones that should return a list of strings will return [TextHandlers](#texthandlers) instead.
TextHandler is a subclass of the standard Python string, so you can do anything with it. So, what is the difference that requires a different naming?
Of course, TextHandler provides extra methods and properties that the standard Python strings can't do. We will review them now, but remember that all methods and properties in all classes that return string(s) are returning TextHandler, which opens the door for creativity and makes the code shorter and cleaner, as you will see. Also, you can import it directly and use it on any string, which we will explain later.
### Usage
First, before discussing the added methods, you need to know that all operations on it, like slicing, accessing by index, etc., and methods like `split`, `replace`, `strip`, etc., all return a TextHandler again, so you can chain them as you want. If you find a method or property that returns a standard string instead of TextHandler, please open an issue, and we will override it as well.
First, we start with the `re` and `re_first` methods. These are the same methods that exist in the rest of the classes ([Adaptor](#adaptor), [Adaptors](#adaptors), and [TextHandlers](#texthandlers)), so they will take the same arguments as well.
The `re` method takes a string/compiled regex pattern as the first argument. It searches the data for all strings matching the regex and returns them as a [TextHandlers](#texthandlers) instance. The `re_first` method takes the same arguments and behaves similarly, but as you probably figured out from the naming, it returns the first result only as a `TextHandler` instance.
Also, it takes other helpful arguments, which are:
- **replace_entities**: This is enabled by default. It replaces character entity references with their corresponding characters.
- **clean_match**: It's disabled by default. This makes the method ignore all whitespaces and consecutive spaces while matching.
- **case_sensitive**: It's enabled by default. As the name implies, disabling it will make the regex ignore letters case while compiling it.
You have seen these examples before; the return result is [TextHandlers](#texthandlers) because we used the `re` method.
```python
>>> page.css('.price_color').re(r'[\d\.]+')
['51.77',
'53.74',
'50.10',
'47.82',
'54.23',
...]
>>> page.css('.product_pod h3 a::attr(href)').re(r'catalogue/(.*)/index.html')
['a-light-in-the-attic_1000',
'tipping-the-velvet_999',
'soumission_998',
'sharp-objects_997',
...]
```
To explain the other arguments better, we will use a custom string for each example below
```python
>>> from scrapling import TextHandler
>>> test_string = TextHandler('hi there') # Hence the two spaces
>>> test_string.re('hi there')
>>> test_string.re('hi there', clean_match=True) # Using `clean_match` will clean the string before matching the regex
['hi there']
>>> test_string2 = TextHandler('Oh, Hi Mark')
>>> test_string2.re_first('oh, hi Mark')
>>> test_string2.re_first('oh, hi Mark', case_sensitive=False) # Hence disabling `case_sensitive`
'Oh, Hi Mark'
# Mixing arguments
>>> test_string.re('hi there', clean_match=True, case_sensitive=False)
['hi There']
```
Another use of the idea of replacing strings with `TextHandler` everywhere is a property like `html_content` returns `TextHandler` so you can do regex on the HTML content if you want:
```python
>>> page.html_content.re('div class=".*">(.*)</div')
['In stock: 5', 'In stock: 3', 'Out of stock']
```
- You also have the `.json()` method, which tries to convert the content to a json object quickly if possible; otherwise, it throws an error
```python
>>> page.css_first('#page-data::text')
'\n {\n "lastUpdated": "2024-09-22T10:30:00Z",\n "totalProducts": 3\n }\n '
>>> page.css_first('#page-data::text').json()
{'lastUpdated': '2024-09-22T10:30:00Z', 'totalProducts': 3}
```
Hence, if you didn't specify a text node while selecting an element (like the text content or an attribute text content), the text content will be selected automatically like this
```python
>>> page.css_first('#page-data').json()
{'lastUpdated': '2024-09-22T10:30:00Z', 'totalProducts': 3}
```
The [Adaptor](#adaptor) class adds one thing here, too; let's say this is the page we are working with:
```html
<html>
<body>
<div>
<script id="page-data" type="application/json">
{
"lastUpdated": "2024-09-22T10:30:00Z",
"totalProducts": 3
}
</script>
</div>
</body>
</html>
```
The [Adaptor](#adaptor) class has the `get_all_text` method, which you should be aware of by now. This method returns a `TextHandler`, of course.<br/><br/>
So, as you know here, if you did something like this
```python
>>> page.css_first('div::text').json()
```
You will get an error because the `div` tag doesn't have direct text content that can be serialized to JSON; it actually doesn't have text content at all.<br/><br/>
In this case, the `get_all_text` method comes to the rescue, so you can do something like that
```python
>>> page.css_first('div').get_all_text(ignore_tags=[]).json()
{'lastUpdated': '2024-09-22T10:30:00Z', 'totalProducts': 3}
```
I used the `ignore_tags` argument here because the default value of it is `('script', 'style',)`, as you are aware.<br/><br/>
Another related behavior you should be aware of is the case while using any of the fetchers, which we will explain later. If you have a JSON response like this example:
```python
>>> page = Adaptor("""{"some_key": "some_value"}""")
```
Because the [Adaptor](#adaptor) class is optimized to deal with HTML pages, it will deal with it as a broken HTML response and fix it, so if you used the `html_content` property, you get this
```python
>>> page.html_content
'<html><body><p>{"some_key": "some_value"}</p></body></html>'
```
Here, you can use `json` method directly, and it will work
```python
>>> page.json()
{'some_key': 'some_value'}
```
You might wonder how this happened while the `html` tag lacks direct text?<br/>
Well, for these cases like JSON responses, I made the `.json()` method inside the [Adaptor](#adaptor) class to check if the current element doesn't have text content; it will use the `get_all_text` method directly.<br/><br/>It might sound hacky a bit but remember, Scrapling is currently optimized to work with HTML pages only so that's the best way till now to handle JSON responses currently without sacrificing speed. This will be changed in the upcoming versions.
- Another handy method is `.clean()`, this will remove all white spaces and consecutive spaces for you and return a new `TextHandler`, wonderful
```python
>>> TextHandler('\n wonderful idea, \reh?').clean()
'wonderful idea, eh?'
```
- Another method that might be helpful in some cases is the `.sort()` method to sort the string for you as you do with lists
```python
>>> TextHandler('acb').sort()
'abc'
```
Or do it in reverse:
```python
>>> TextHandler('acb').sort(reverse=True)
'cba'
```
Other methods and properties will be added over time, but remember that this class is returned in place of strings nearly everywhere in the library.
## TextHandlers
You probably guessed it: This class is similar to [Adaptors](#adaptors) and [Adaptor](#adaptor), but here it inherits the same logic and method as standard lists, with only `re` and `re_first` as new methods.
The only difference is that the `re_first` method logic here does `re` on each [TextHandler](#texthandler) within and returns the first result it has or `None`. Nothing is new to explain here, but new methods will be added here with time.
## AttributesHandler
This is a read-only version of Python's standard dictionary or `dict` that's only used to store the attributes of each element or each [Adaptor](#adaptor) instance, in other words.
```python
>>> print(page.find('script').attrib)
{'id': 'page-data', 'type': 'application/json'}
>>> type(page.find('script').attrib).__name__
'AttributesHandler'
```
Because it's read-only, it will use fewer resources than the standard dictionary. Still, it has the same dictionary method/properties other than those allowing you to modify/override the data.
It currently adds two extra simple methods:
- The `search_values` method
In standard dictionaries, you can do `dict.get("key_name")` to check if a key exists. However, if you want to search by values instead of keys, it will take you some code lines. This method does that for you. It allows you to search the current attributes by values and returns a dictionary of each matching item.
A simple example would be
```python
>>> for i in page.find('script').attrib.search_values('page-data'):
print(i)
{'id': 'page-data'}
```
But this method provides the `partial` argument as well, which allows you to search by part of the value:
```python
>>> for i in page.find('script').attrib.search_values('page', partial=True):
print(i)
{'id': 'page-data'}
```
These examples won't happen in the real world; most likely, a more real-world example would be using it with the `find_all` method to find all elements that have a specific value in their arguments:
```python
>>> page.find_all(lambda element: list(element.attrib.search_values('product')))
[<data='<article class="product" data-id="1"><h3...' parent='<div class="product-list"> <article clas...'>,
<data='<article class="product" data-id="2"><h3...' parent='<div class="product-list"> <article clas...'>,
<data='<article class="product" data-id="3"><h3...' parent='<div class="product-list"> <article clas...'>]
```
All these elements have 'product' as a value for the attribute `class`.
Hence, I used the `list` function here because `search_values` returns a generator, so it would be `True` for all elements.
- The `json_string` property
This property converts current attributes to JSON string if the attributes are JSON serializable; otherwise, it throws an error
```python
>>> page.find('script').attrib.json_string
b'{"id":"page-data","type":"application/json"}'
```
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