Files
Scrapling/scrapling/engines/toolbelt/custom.py
T
2025-09-13 03:22:53 +03:00

305 lines
10 KiB
Python

"""
Functions related to custom types or type checking
"""
from email.message import Message
from scrapling.core._types import (
Any,
Dict,
List,
Optional,
Tuple,
)
from scrapling.core.custom_types import MappingProxyType
from scrapling.core.utils import log, lru_cache
from scrapling.parser import Selector, SQLiteStorageSystem
class ResponseEncoding:
__DEFAULT_ENCODING = "utf-8"
__ISO_8859_1_CONTENT_TYPES = {
"text/plain",
"text/html",
"text/css",
"text/javascript",
}
@classmethod
@lru_cache(maxsize=128)
def __parse_content_type(cls, header_value: str) -> Tuple[str, Dict[str, str]]:
"""Parse content type and parameters from a content-type header value.
Uses `email.message.Message` for robust header parsing according to RFC 2045.
:param header_value: Raw content-type header string
:return: Tuple of (content_type, parameters_dict)
"""
# Create a Message object and set the Content-Type header then get the content type and parameters
msg = Message()
msg["content-type"] = header_value
content_type = msg.get_content_type()
params = dict(msg.get_params(failobj=[]))
# Remove the content-type from params if present somehow
params.pop("content-type", None)
return content_type, params
@classmethod
@lru_cache(maxsize=128)
def get_value(cls, content_type: Optional[str], text: Optional[str] = "test") -> str:
"""Determine the appropriate character encoding from a content-type header.
The encoding is determined by these rules in order:
1. If no content-type is provided, use UTF-8
2. If charset parameter is present, use that encoding
3. If content-type is `text/*`, use ISO-8859-1 per HTTP/1.1 spec
4. If content-type is application/json, use UTF-8 per RFC 4627
5. Default to UTF-8 if nothing else matches
:param content_type: Content-Type header value or None
:param text: A text to test the encoding on it
:return: String naming the character encoding
"""
if not content_type:
return cls.__DEFAULT_ENCODING
try:
encoding = None
content_type, params = cls.__parse_content_type(content_type)
# First check for explicit charset parameter
if "charset" in params:
encoding = params["charset"].strip("'\"")
# Apply content-type specific rules
elif content_type in cls.__ISO_8859_1_CONTENT_TYPES:
encoding = "ISO-8859-1"
elif content_type == "application/json":
encoding = cls.__DEFAULT_ENCODING
if encoding:
_ = text.encode(encoding) # Validate encoding and validate it can encode the given text
return encoding
return cls.__DEFAULT_ENCODING
except (ValueError, LookupError, UnicodeEncodeError):
return cls.__DEFAULT_ENCODING
class Response(Selector):
"""This class is returned by all engines as a way to unify response type between different libraries."""
def __init__(
self,
url: str,
content: str | bytes,
status: int,
reason: str,
cookies: Tuple[Dict[str, str], ...] | Dict[str, str],
headers: Dict,
request_headers: Dict,
encoding: str = "utf-8",
method: str = "GET",
history: List = None,
**selector_config: Dict,
):
adaptive_domain = selector_config.pop("adaptive_domain", None)
self.status = status
self.reason = reason
self.cookies = cookies
self.headers = headers
self.request_headers = request_headers
self.history = history or []
encoding = ResponseEncoding.get_value(
encoding, content.decode("utf-8") if isinstance(content, bytes) else content
)
super().__init__(
content=content,
url=adaptive_domain or url,
encoding=encoding,
**selector_config,
)
# For easier debugging while working from a Python shell
log.info(f"Fetched ({status}) <{method} {url}> (referer: {request_headers.get('referer')})")
class BaseFetcher:
__slots__ = ()
huge_tree: bool = True
adaptive: Optional[bool] = False
storage: Any = SQLiteStorageSystem
keep_cdata: Optional[bool] = False
storage_args: Optional[Dict] = None
keep_comments: Optional[bool] = False
adaptive_domain: Optional[str] = None
parser_keywords: Tuple = (
"huge_tree",
"adaptive",
"storage",
"keep_cdata",
"storage_args",
"keep_comments",
"adaptive_domain",
) # Left open for the user
def __init__(self, *args, **kwargs):
# For backward-compatibility before 0.2.99
args_str = ", ".join(args) or ""
kwargs_str = ", ".join(f"{k}={v}" for k, v in kwargs.items()) or ""
if args_str:
args_str += ", "
log.warning(
f"This logic is deprecated now, and have no effect; It will be removed with v0.3. Use `{self.__class__.__name__}.configure({args_str}{kwargs_str})` instead before fetching"
)
pass
@classmethod
def display_config(cls):
return dict(
huge_tree=cls.huge_tree,
keep_comments=cls.keep_comments,
keep_cdata=cls.keep_cdata,
adaptive=cls.adaptive,
storage=cls.storage,
storage_args=cls.storage_args,
adaptive_domain=cls.adaptive_domain,
)
@classmethod
def configure(cls, **kwargs):
"""Set multiple arguments for the parser at once globally
:param kwargs: The keywords can be any arguments of the following: huge_tree, keep_comments, keep_cdata, adaptive, storage, storage_args, adaptive_domain
"""
for key, value in kwargs.items():
key = key.strip().lower()
if hasattr(cls, key):
if key in cls.parser_keywords:
setattr(cls, key, value)
else:
# Yup, no fun allowed LOL
raise AttributeError(f'Unknown parser argument: "{key}"; maybe you meant {cls.parser_keywords}?')
else:
raise ValueError(f'Unknown parser argument: "{key}"; maybe you meant {cls.parser_keywords}?')
if not kwargs:
raise AttributeError(f"You must pass a keyword to configure, current keywords: {cls.parser_keywords}?")
@classmethod
def _generate_parser_arguments(cls) -> Dict:
# Selector class parameters
# I won't validate Selector's class parameters here again, I will leave it to be validated later
parser_arguments = dict(
huge_tree=cls.huge_tree,
keep_comments=cls.keep_comments,
keep_cdata=cls.keep_cdata,
adaptive=cls.adaptive,
storage=cls.storage,
storage_args=cls.storage_args,
)
if cls.adaptive_domain:
if not isinstance(cls.adaptive_domain, str):
log.warning('[Ignored] The argument "adaptive_domain" must be of string type')
else:
parser_arguments.update({"adaptive_domain": cls.adaptive_domain})
return parser_arguments
class StatusText:
"""A class that gets the status text of response status code.
Reference: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status
"""
_phrases = MappingProxyType(
{
100: "Continue",
101: "Switching Protocols",
102: "Processing",
103: "Early Hints",
200: "OK",
201: "Created",
202: "Accepted",
203: "Non-Authoritative Information",
204: "No Content",
205: "Reset Content",
206: "Partial Content",
207: "Multi-Status",
208: "Already Reported",
226: "IM Used",
300: "Multiple Choices",
301: "Moved Permanently",
302: "Found",
303: "See Other",
304: "Not Modified",
305: "Use Proxy",
307: "Temporary Redirect",
308: "Permanent Redirect",
400: "Bad Request",
401: "Unauthorized",
402: "Payment Required",
403: "Forbidden",
404: "Not Found",
405: "Method Not Allowed",
406: "Not Acceptable",
407: "Proxy Authentication Required",
408: "Request Timeout",
409: "Conflict",
410: "Gone",
411: "Length Required",
412: "Precondition Failed",
413: "Payload Too Large",
414: "URI Too Long",
415: "Unsupported Media Type",
416: "Range Not Satisfiable",
417: "Expectation Failed",
418: "I'm a teapot",
421: "Misdirected Request",
422: "Unprocessable Entity",
423: "Locked",
424: "Failed Dependency",
425: "Too Early",
426: "Upgrade Required",
428: "Precondition Required",
429: "Too Many Requests",
431: "Request Header Fields Too Large",
451: "Unavailable For Legal Reasons",
500: "Internal Server Error",
501: "Not Implemented",
502: "Bad Gateway",
503: "Service Unavailable",
504: "Gateway Timeout",
505: "HTTP Version Not Supported",
506: "Variant Also Negotiates",
507: "Insufficient Storage",
508: "Loop Detected",
510: "Not Extended",
511: "Network Authentication Required",
}
)
@classmethod
@lru_cache(maxsize=128)
def get(cls, status_code: int) -> str:
"""Get the phrase for a given HTTP status code."""
return cls._phrases.get(status_code, "Unknown Status Code")
def get_variable_name(var: Any) -> Optional[str]:
"""Get the name of a variable using global and local scopes.
:param var: The variable to find the name for
:return: The name of the variable if found, None otherwise
"""
for scope in [globals(), locals()]:
for name, value in scope.items():
if value is var:
return name
return None