Skip to main content

A library for converting any text (xml, html, plain text, stdout, etc) to python datatypes

Project description

Hatch project Documentation Status CI License Version Python-versions codecov

Scrape-schema

This library is designed to write structured, readable, reusable parsers for html, raw text and is inspired by dataclasses

!!! Scrape-schema is currently in Pre-Alpha. Please expect breaking changes.

Motivation

Simplifying parsers support, where it is difficult to use or the complete absence of the API interfaces and decrease lines of code

Also structuring, data serialization and use as an intermediate layer for third-party serialization libraries: json, dataclasses, pydantic, etc


Features

  • Parsel backend.
  • re, css, xpath, jmespath, chompjs features
  • Fluent interface simulate original parsel.Selector API for easy to use.
  • does not depend on the http client implementation, use any!
  • Python 3.8+ support
  • Dataclass-like structure
  • Partial support auto type-casting from annotations (str, int, float, bool, list, dict, Optional)
  • logging to quickly find problems in extracted values

Install

pip install scrape-schema

Example

The fields interface is similar to the original parsel

# Example from parsel documentation
>>> from parsel import Selector
>>> text = """
        <html>
            <body>
                <h1>Hello, Parsel!</h1>
                <ul>
                    <li><a href="http://example.com">Link 1</a></li>
                    <li><a href="http://scrapy.org">Link 2</a></li>
                </ul>
                <script type="application/json">{"a": ["b", "c"]}</script>
            </body>
        </html>"""
>>> selector = Selector(text=text)
>>> selector.css('h1::text').get()
'Hello, Parsel!'
>>> selector.xpath('//h1/text()').re(r'\w+')
['Hello', 'Parsel']
>>> for li in selector.css('ul > li'):
...     print(li.xpath('.//@href').get())
http://example.com
http://scrapy.org
>>> selector.css('script::text').jmespath("a").get()
'b'
>>> selector.css('script::text').jmespath("a").getall()
['b', 'c']
from scrape_schema import BaseSchema, Parsel, Sc


class Schema(BaseSchema):
    h1: Sc[str, Parsel().css('h1::text').get()]
    words: Sc[list[str], Parsel().xpath('//h1/text()').re(r'\w+')]
    urls: Sc[list[str], Parsel().css('ul > li').xpath('.//@href').getall()]
    sample_jmespath_1: Sc[str, Parsel().css('script::text').jmespath("a").get()]
    sample_jmespath_2: Sc[list[str], Parsel().css('script::text').jmespath("a").getall()]


text = """
        <html>
            <body>
                <h1>Hello, Parsel!</h1>
                <ul>
                    <li><a href="http://example.com">Link 1</a></li>
                    <li><a href="http://scrapy.org">Link 2</a></li>
                </ul>
                <script type="application/json">{"a": ["b", "c"]}</script>
            </body>
        </html>"""

print(Schema(text).dict())
# {'h1': 'Hello, Parsel!',
# 'words': ['Hello', 'Parsel'],
# 'urls': ['http://example.com', 'http://scrapy.org'],
# 'sample_jmespath_1': 'b',
# 'sample_jmespath_2': ['b', 'c']}

Code comparison

html

parsel:

from parsel import Selector
import pprint
import requests


def original_parsel(resp: str):
    sel = Selector(resp)
    __RATINGS = {"One": 1, "Two": 2, "Three": 3, "Four": 4, "Five": 5}
    data: dict[str, list[dict]] = {"books": []}
    for book_sel in sel.xpath(".//section/div/ol[@class='row']/li"):
        if url := book_sel.xpath('//div[@class="image_container"]/a/@href').get():
            url = f"https://books.toscrape.com/catalogue/{url}"
        if image := book_sel.xpath('//div[@class="image_container"]/a/img/@src').get():
            image = f"https://books.toscrape.com{image[2:]}"
        if price := book_sel.xpath('//div[@class="product_price"]/p[@class="price_color"]/text()').get():
            price = float(price[2:])
        else:
            price = .0
        name = book_sel.xpath("//h3/a/@title").get()
        available = book_sel.xpath('//div[@class="product_price"]/p[@class="instock availability"]/i').attrib.get('class')
        available = ('icon-ok' in available)
        rating = book_sel.xpath('//p[contains(@class, "star-rating")]').attrib.get('class')
        rating = __RATINGS.get(rating.split()[-1], 0)
        data['books'].append(dict(url=url, image=image, price=price, name=name, available=available, rating=rating))
    return data


if __name__ == '__main__':
    response = requests.get("https://books.toscrape.com/catalogue/page-2.html").text
    pprint.pprint(original_parsel(response), compact=True)

scrape_schema:

from typing import List
import pprint
import requests
from scrape_schema import BaseSchema, Sc, Nested, sc_param, Parsel


class Book(BaseSchema):
    __RATINGS = {"One": 1, "Two": 2, "Three": 3, "Four": 4, "Five": 5}
    url: Sc[str, (Parsel()
                  .xpath('//div[@class="image_container"]/a/@href')
                  .get()
                  .concat_l("https://books.toscrape.com/catalogue/"))]
    image: Sc[str, (Parsel()
                    .xpath('//div[@class="image_container"]/a/img/@src')
                    .get()[2:]
                    .concat_l("https://books.toscrape.com"))]
    price: Sc[float, (Parsel(default=.0)
                      .xpath('//div[@class="product_price"]/p[@class="price_color"]/text()')
                      .get()[2:])]
    name: Sc[str, Parsel().xpath("//h3/a/@title").get()]
    available: Sc[bool, (Parsel()
                         .xpath('//div[@class="product_price"]/p[@class="instock availability"]/i')
                         .attrib['class']
                         .fn(lambda s: s == 'icon-ok')  # check available tag
                         )]
    _rating: Sc[str, Parsel().xpath('//p[contains(@class, "star-rating")]').attrib.get(key='class')]

    @sc_param
    def rating(self) -> int:
        return self.__RATINGS.get(self._rating.split()[-1], 0)


class MainPage(BaseSchema):
    books: Sc[List[Book], Nested(Parsel().xpath(".//section/div/ol[@class='row']/li").getall())]


if __name__ == '__main__':
    response = requests.get("https://books.toscrape.com/catalogue/page-2.html").text
    pprint.pprint(MainPage(response).dict(), compact=True)

raw text

original re:

import re
import pprint

TEXT = """
banana potato BANANA POTATO
-foo:10
-bar:20
lorem upsum dolor
192.168.0.1
"""


def parse_text(text: str) -> dict:
    if match := re.search(r"(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})", text):
        ipv4 = match[1]
    else:
        ipv4 = None

    if matches := re.findall(r"(\d+)", text):
        max_digit = max(int(i) for i in matches)
    else:
        max_digit = None

    failed_value = bool(re.search(r"(ora)", text))

    if matches := re.findall(r"(\d+)", text):
        digits = [int(i) for i in matches]
        digits_float = [float(f'{i}.5') for i in matches]
    else:
        digits = None
        digits_float = None
    words_lower = matches if (matches := re.findall(r"([a-z]+)", text)) else None
    words_upper = matches if (matches := re.findall(r"([A-Z]+)", text)) else None

    return dict(ipv4=ipv4, max_digit=max_digit, failed_value=failed_value,
                digits=digits, digits_float=digits_float, 
                words_lower=words_lower, words_upper=words_upper)
    

if __name__ == '__main__':
    pprint.pprint(parse_text(TEXT), width=48, compact=True)
    # {'digits': [10, 20, 192, 168, 0, 1],
    #  'digits_float': [10.5, 20.5, 192.5, 168.5, 0.5,
    #                   1.5],
    #  'failed_value': False,
    #  'ip_v4': '192.168.0.1',
    #  'max_digit': 192,
    #  'words_lower': ['banana', 'potato', 'foo',
    #                  'bar', 'lorem', 'upsum',
    #                  'dolor'],
    #  'words_upper': ['BANANA', 'POTATO']}

scrape_schema:

from typing import List  # if you usage python3.8. If python3.9 - use build-in list
import pprint
from scrape_schema import Parsel, BaseSchema, Sc, sc_param

# Note: `Sc` is shortcut typing.Annotated

TEXT = """
banana potato BANANA POTATO
-foo:10
-bar:20
lorem upsum dolor
192.168.0.1
"""


class MySchema(BaseSchema):
    ipv4: Sc[str, Parsel(raw=True).re_search(r"(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})")[1]]
    failed_value: Sc[bool, Parsel(default=False, raw=True).re_search(r"(ora)")[1]]
    digits: Sc[List[int], Parsel(raw=True).re_findall(r"(\d+)")]
    digits_float: Sc[List[float], Parsel(raw=True).re_findall(r"(\d+)").fn(lambda lst: [f"{s}.5" for s in lst])]
    words_lower: Sc[List[str], Parsel(raw=True).re_findall("([a-z]+)")]
    words_upper: Sc[List[str], Parsel(raw=True).re_findall(r"([A-Z]+)")]

    @sc_param
    def sum(self):
        return sum(self.digits)
    
    @sc_param
    def max_digit(self):
        return max(self.digits)

    @sc_param
    def all_words(self):
        return self.words_lower + self.words_upper


if __name__ == '__main__':
    pprint.pprint(MySchema(TEXT).dict(), compact=True)
# {'all_words': ['banana', 'potato', 'foo', 'bar', 'lorem', 'upsum', 'dolor',
#                'BANANA', 'POTATO'],
#  'digits': [10, 20, 192, 168, 0, 1],
#  'digits_float': [10.5, 20.5, 192.5, 168.5, 0.5, 1.5],
#  'failed_value': False,
#  'ipv4': '192.168.0.1',
#  'max_digit': 192,
#  'sum': 391,
#  'words_lower': ['banana', 'potato', 'foo', 'bar', 'lorem', 'upsum', 'dolor'],
#  'words_upper': ['BANANA', 'POTATO']}

logging

In this project, logging to the DEBUG level is enabled by default.

To set up logger, you can get it by the name "scrape_schema"

import logging

logger = logging.getLogger("scrape_schema")
logger.setLevel(logging.INFO)
...

See more examples and documentation for get more information/examples


This project is licensed under the terms of the MIT license.

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

scrape_schema-0.3.5.tar.gz (13.9 kB view details)

Uploaded Source

Built Distribution

scrape_schema-0.3.5-py3-none-any.whl (16.5 kB view details)

Uploaded Python 3

File details

Details for the file scrape_schema-0.3.5.tar.gz.

File metadata

  • Download URL: scrape_schema-0.3.5.tar.gz
  • Upload date:
  • Size: 13.9 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No
  • Uploaded via: python-httpx/0.24.0

File hashes

Hashes for scrape_schema-0.3.5.tar.gz
Algorithm Hash digest
SHA256 d43bbf143ef5722a3a3cec480751a7fd896a246059b33c4bfc71eb552e7de8ff
MD5 94153ec7b73263de084af13853b85550
BLAKE2b-256 526a9f29be006e802aed0db76f87dcafcfa2864611f84d9a6cc6a4aa0c176d7a

See more details on using hashes here.

File details

Details for the file scrape_schema-0.3.5-py3-none-any.whl.

File metadata

File hashes

Hashes for scrape_schema-0.3.5-py3-none-any.whl
Algorithm Hash digest
SHA256 56e599fe7dd0c0540ca821c546cc1b14393eaa55ffbba967135b8c6d402b1af7
MD5 4356758ad7a4db24b29689d8737a20ba
BLAKE2b-256 36f1a5394fb1a3df05fbad4f9eaa7e81e2bc74f19ee6be1c5b260774464ba489

See more details on using hashes here.

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page