| | """ |
| | :mod:`pandas.io.xml` is a module for reading XML. |
| | """ |
| |
|
| | from __future__ import annotations |
| |
|
| | import io |
| | from typing import ( |
| | Any, |
| | Callable, |
| | Sequence, |
| | ) |
| |
|
| | from pandas._libs import lib |
| | from pandas._typing import ( |
| | TYPE_CHECKING, |
| | CompressionOptions, |
| | ConvertersArg, |
| | DtypeArg, |
| | DtypeBackend, |
| | FilePath, |
| | ParseDatesArg, |
| | ReadBuffer, |
| | StorageOptions, |
| | XMLParsers, |
| | ) |
| | from pandas.compat._optional import import_optional_dependency |
| | from pandas.errors import ( |
| | AbstractMethodError, |
| | ParserError, |
| | ) |
| | from pandas.util._decorators import doc |
| | from pandas.util._validators import check_dtype_backend |
| |
|
| | from pandas.core.dtypes.common import is_list_like |
| |
|
| | from pandas.core.shared_docs import _shared_docs |
| |
|
| | from pandas.io.common import ( |
| | file_exists, |
| | get_handle, |
| | infer_compression, |
| | is_fsspec_url, |
| | is_url, |
| | stringify_path, |
| | ) |
| | from pandas.io.parsers import TextParser |
| |
|
| | if TYPE_CHECKING: |
| | from xml.etree.ElementTree import Element |
| |
|
| | from lxml import etree |
| |
|
| | from pandas import DataFrame |
| |
|
| |
|
| | @doc( |
| | storage_options=_shared_docs["storage_options"], |
| | decompression_options=_shared_docs["decompression_options"] % "path_or_buffer", |
| | ) |
| | class _XMLFrameParser: |
| | """ |
| | Internal subclass to parse XML into DataFrames. |
| | |
| | Parameters |
| | ---------- |
| | path_or_buffer : a valid JSON str, path object or file-like object |
| | Any valid string path is acceptable. The string could be a URL. Valid |
| | URL schemes include http, ftp, s3, and file. |
| | |
| | xpath : str or regex |
| | The XPath expression to parse required set of nodes for |
| | migration to `Data Frame`. `etree` supports limited XPath. |
| | |
| | namespaces : dict |
| | The namespaces defined in XML document (`xmlns:namespace='URI') |
| | as dicts with key being namespace and value the URI. |
| | |
| | elems_only : bool |
| | Parse only the child elements at the specified `xpath`. |
| | |
| | attrs_only : bool |
| | Parse only the attributes at the specified `xpath`. |
| | |
| | names : list |
| | Column names for Data Frame of parsed XML data. |
| | |
| | dtype : dict |
| | Data type for data or columns. E.g. {{'a': np.float64, |
| | 'b': np.int32, 'c': 'Int64'}} |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | converters : dict, optional |
| | Dict of functions for converting values in certain columns. Keys can |
| | either be integers or column labels. |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | parse_dates : bool or list of int or names or list of lists or dict |
| | Converts either index or select columns to datetimes |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | encoding : str |
| | Encoding of xml object or document. |
| | |
| | stylesheet : str or file-like |
| | URL, file, file-like object, or a raw string containing XSLT, |
| | `etree` does not support XSLT but retained for consistency. |
| | |
| | iterparse : dict, optional |
| | Dict with row element as key and list of descendant elements |
| | and/or attributes as value to be retrieved in iterparsing of |
| | XML document. |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | {decompression_options} |
| | |
| | .. versionchanged:: 1.4.0 Zstandard support. |
| | |
| | {storage_options} |
| | |
| | See also |
| | -------- |
| | pandas.io.xml._EtreeFrameParser |
| | pandas.io.xml._LxmlFrameParser |
| | |
| | Notes |
| | ----- |
| | To subclass this class effectively you must override the following methods:` |
| | * :func:`parse_data` |
| | * :func:`_parse_nodes` |
| | * :func:`_iterparse_nodes` |
| | * :func:`_parse_doc` |
| | * :func:`_validate_names` |
| | * :func:`_validate_path` |
| | |
| | |
| | See each method's respective documentation for details on their |
| | functionality. |
| | """ |
| |
|
| | def __init__( |
| | self, |
| | path_or_buffer: FilePath | ReadBuffer[bytes] | ReadBuffer[str], |
| | xpath: str, |
| | namespaces: dict[str, str] | None, |
| | elems_only: bool, |
| | attrs_only: bool, |
| | names: Sequence[str] | None, |
| | dtype: DtypeArg | None, |
| | converters: ConvertersArg | None, |
| | parse_dates: ParseDatesArg | None, |
| | encoding: str | None, |
| | stylesheet: FilePath | ReadBuffer[bytes] | ReadBuffer[str] | None, |
| | iterparse: dict[str, list[str]] | None, |
| | compression: CompressionOptions, |
| | storage_options: StorageOptions, |
| | ) -> None: |
| | self.path_or_buffer = path_or_buffer |
| | self.xpath = xpath |
| | self.namespaces = namespaces |
| | self.elems_only = elems_only |
| | self.attrs_only = attrs_only |
| | self.names = names |
| | self.dtype = dtype |
| | self.converters = converters |
| | self.parse_dates = parse_dates |
| | self.encoding = encoding |
| | self.stylesheet = stylesheet |
| | self.iterparse = iterparse |
| | self.is_style = None |
| | self.compression = compression |
| | self.storage_options = storage_options |
| |
|
| | def parse_data(self) -> list[dict[str, str | None]]: |
| | """ |
| | Parse xml data. |
| | |
| | This method will call the other internal methods to |
| | validate xpath, names, parse and return specific nodes. |
| | """ |
| |
|
| | raise AbstractMethodError(self) |
| |
|
| | def _parse_nodes(self, elems: list[Any]) -> list[dict[str, str | None]]: |
| | """ |
| | Parse xml nodes. |
| | |
| | This method will parse the children and attributes of elements |
| | in xpath, conditionally for only elements, only attributes |
| | or both while optionally renaming node names. |
| | |
| | Raises |
| | ------ |
| | ValueError |
| | * If only elements and only attributes are specified. |
| | |
| | Notes |
| | ----- |
| | Namespace URIs will be removed from return node values. Also, |
| | elements with missing children or attributes compared to siblings |
| | will have optional keys filled with None values. |
| | """ |
| |
|
| | dicts: list[dict[str, str | None]] |
| |
|
| | if self.elems_only and self.attrs_only: |
| | raise ValueError("Either element or attributes can be parsed not both.") |
| | if self.elems_only: |
| | if self.names: |
| | dicts = [ |
| | { |
| | **( |
| | {el.tag: el.text.strip()} |
| | if el.text and not el.text.isspace() |
| | else {} |
| | ), |
| | **{ |
| | nm: ch.text.strip() if ch.text else None |
| | for nm, ch in zip(self.names, el.findall("*")) |
| | }, |
| | } |
| | for el in elems |
| | ] |
| | else: |
| | dicts = [ |
| | { |
| | ch.tag: ch.text.strip() if ch.text else None |
| | for ch in el.findall("*") |
| | } |
| | for el in elems |
| | ] |
| |
|
| | elif self.attrs_only: |
| | dicts = [ |
| | {k: v.strip() if v else None for k, v in el.attrib.items()} |
| | for el in elems |
| | ] |
| |
|
| | else: |
| | if self.names: |
| | dicts = [ |
| | { |
| | **el.attrib, |
| | **( |
| | {el.tag: el.text.strip()} |
| | if el.text and not el.text.isspace() |
| | else {} |
| | ), |
| | **{ |
| | nm: ch.text.strip() if ch.text else None |
| | for nm, ch in zip(self.names, el.findall("*")) |
| | }, |
| | } |
| | for el in elems |
| | ] |
| |
|
| | else: |
| | dicts = [ |
| | { |
| | **el.attrib, |
| | **( |
| | {el.tag: el.text.strip()} |
| | if el.text and not el.text.isspace() |
| | else {} |
| | ), |
| | **{ |
| | ch.tag: ch.text.strip() if ch.text else None |
| | for ch in el.findall("*") |
| | }, |
| | } |
| | for el in elems |
| | ] |
| |
|
| | dicts = [ |
| | {k.split("}")[1] if "}" in k else k: v for k, v in d.items()} for d in dicts |
| | ] |
| |
|
| | keys = list(dict.fromkeys([k for d in dicts for k in d.keys()])) |
| | dicts = [{k: d[k] if k in d.keys() else None for k in keys} for d in dicts] |
| |
|
| | if self.names: |
| | dicts = [dict(zip(self.names, d.values())) for d in dicts] |
| |
|
| | return dicts |
| |
|
| | def _iterparse_nodes(self, iterparse: Callable) -> list[dict[str, str | None]]: |
| | """ |
| | Iterparse xml nodes. |
| | |
| | This method will read in local disk, decompressed XML files for elements |
| | and underlying descendants using iterparse, a method to iterate through |
| | an XML tree without holding entire XML tree in memory. |
| | |
| | Raises |
| | ------ |
| | TypeError |
| | * If `iterparse` is not a dict or its dict value is not list-like. |
| | ParserError |
| | * If `path_or_buffer` is not a physical file on disk or file-like object. |
| | * If no data is returned from selected items in `iterparse`. |
| | |
| | Notes |
| | ----- |
| | Namespace URIs will be removed from return node values. Also, |
| | elements with missing children or attributes in submitted list |
| | will have optional keys filled with None values. |
| | """ |
| |
|
| | dicts: list[dict[str, str | None]] = [] |
| | row: dict[str, str | None] | None = None |
| |
|
| | if not isinstance(self.iterparse, dict): |
| | raise TypeError( |
| | f"{type(self.iterparse).__name__} is not a valid type for iterparse" |
| | ) |
| |
|
| | row_node = next(iter(self.iterparse.keys())) if self.iterparse else "" |
| | if not is_list_like(self.iterparse[row_node]): |
| | raise TypeError( |
| | f"{type(self.iterparse[row_node])} is not a valid type " |
| | "for value in iterparse" |
| | ) |
| |
|
| | if (not hasattr(self.path_or_buffer, "read")) and ( |
| | not isinstance(self.path_or_buffer, str) |
| | or is_url(self.path_or_buffer) |
| | or is_fsspec_url(self.path_or_buffer) |
| | or self.path_or_buffer.startswith(("<?xml", "<")) |
| | or infer_compression(self.path_or_buffer, "infer") is not None |
| | ): |
| | raise ParserError( |
| | "iterparse is designed for large XML files that are fully extracted on " |
| | "local disk and not as compressed files or online sources." |
| | ) |
| |
|
| | iterparse_repeats = len(self.iterparse[row_node]) != len( |
| | set(self.iterparse[row_node]) |
| | ) |
| |
|
| | for event, elem in iterparse(self.path_or_buffer, events=("start", "end")): |
| | curr_elem = elem.tag.split("}")[1] if "}" in elem.tag else elem.tag |
| |
|
| | if event == "start": |
| | if curr_elem == row_node: |
| | row = {} |
| |
|
| | if row is not None: |
| | if self.names and iterparse_repeats: |
| | for col, nm in zip(self.iterparse[row_node], self.names): |
| | if curr_elem == col: |
| | elem_val = elem.text.strip() if elem.text else None |
| | if elem_val not in row.values() and nm not in row: |
| | row[nm] = elem_val |
| |
|
| | if col in elem.attrib: |
| | if elem.attrib[col] not in row.values() and nm not in row: |
| | row[nm] = elem.attrib[col] |
| | else: |
| | for col in self.iterparse[row_node]: |
| | if curr_elem == col: |
| | row[col] = elem.text.strip() if elem.text else None |
| | if col in elem.attrib: |
| | row[col] = elem.attrib[col] |
| |
|
| | if event == "end": |
| | if curr_elem == row_node and row is not None: |
| | dicts.append(row) |
| | row = None |
| |
|
| | elem.clear() |
| | if hasattr(elem, "getprevious"): |
| | while ( |
| | elem.getprevious() is not None and elem.getparent() is not None |
| | ): |
| | del elem.getparent()[0] |
| |
|
| | if dicts == []: |
| | raise ParserError("No result from selected items in iterparse.") |
| |
|
| | keys = list(dict.fromkeys([k for d in dicts for k in d.keys()])) |
| | dicts = [{k: d[k] if k in d.keys() else None for k in keys} for d in dicts] |
| |
|
| | if self.names: |
| | dicts = [dict(zip(self.names, d.values())) for d in dicts] |
| |
|
| | return dicts |
| |
|
| | def _validate_path(self) -> list[Any]: |
| | """ |
| | Validate xpath. |
| | |
| | This method checks for syntax, evaluation, or empty nodes return. |
| | |
| | Raises |
| | ------ |
| | SyntaxError |
| | * If xpah is not supported or issues with namespaces. |
| | |
| | ValueError |
| | * If xpah does not return any nodes. |
| | """ |
| |
|
| | raise AbstractMethodError(self) |
| |
|
| | def _validate_names(self) -> None: |
| | """ |
| | Validate names. |
| | |
| | This method will check if names is a list-like and aligns |
| | with length of parse nodes. |
| | |
| | Raises |
| | ------ |
| | ValueError |
| | * If value is not a list and less then length of nodes. |
| | """ |
| | raise AbstractMethodError(self) |
| |
|
| | def _parse_doc( |
| | self, raw_doc: FilePath | ReadBuffer[bytes] | ReadBuffer[str] |
| | ) -> Element | etree._Element: |
| | """ |
| | Build tree from path_or_buffer. |
| | |
| | This method will parse XML object into tree |
| | either from string/bytes or file location. |
| | """ |
| | raise AbstractMethodError(self) |
| |
|
| |
|
| | class _EtreeFrameParser(_XMLFrameParser): |
| | """ |
| | Internal class to parse XML into DataFrames with the Python |
| | standard library XML module: `xml.etree.ElementTree`. |
| | """ |
| |
|
| | def parse_data(self) -> list[dict[str, str | None]]: |
| | from xml.etree.ElementTree import iterparse |
| |
|
| | if self.stylesheet is not None: |
| | raise ValueError( |
| | "To use stylesheet, you need lxml installed and selected as parser." |
| | ) |
| |
|
| | if self.iterparse is None: |
| | self.xml_doc = self._parse_doc(self.path_or_buffer) |
| | elems = self._validate_path() |
| |
|
| | self._validate_names() |
| |
|
| | xml_dicts: list[dict[str, str | None]] = ( |
| | self._parse_nodes(elems) |
| | if self.iterparse is None |
| | else self._iterparse_nodes(iterparse) |
| | ) |
| |
|
| | return xml_dicts |
| |
|
| | def _validate_path(self) -> list[Any]: |
| | """ |
| | Notes |
| | ----- |
| | `etree` supports limited XPath. If user attempts a more complex |
| | expression syntax error will raise. |
| | """ |
| |
|
| | msg = ( |
| | "xpath does not return any nodes or attributes. " |
| | "Be sure to specify in `xpath` the parent nodes of " |
| | "children and attributes to parse. " |
| | "If document uses namespaces denoted with " |
| | "xmlns, be sure to define namespaces and " |
| | "use them in xpath." |
| | ) |
| | try: |
| | elems = self.xml_doc.findall(self.xpath, namespaces=self.namespaces) |
| | children = [ch for el in elems for ch in el.findall("*")] |
| | attrs = {k: v for el in elems for k, v in el.attrib.items()} |
| |
|
| | if elems is None: |
| | raise ValueError(msg) |
| |
|
| | if elems is not None: |
| | if self.elems_only and children == []: |
| | raise ValueError(msg) |
| | if self.attrs_only and attrs == {}: |
| | raise ValueError(msg) |
| | if children == [] and attrs == {}: |
| | raise ValueError(msg) |
| |
|
| | except (KeyError, SyntaxError): |
| | raise SyntaxError( |
| | "You have used an incorrect or unsupported XPath " |
| | "expression for etree library or you used an " |
| | "undeclared namespace prefix." |
| | ) |
| |
|
| | return elems |
| |
|
| | def _validate_names(self) -> None: |
| | children: list[Any] |
| |
|
| | if self.names: |
| | if self.iterparse: |
| | children = self.iterparse[next(iter(self.iterparse))] |
| | else: |
| | parent = self.xml_doc.find(self.xpath, namespaces=self.namespaces) |
| | children = parent.findall("*") if parent else [] |
| |
|
| | if is_list_like(self.names): |
| | if len(self.names) < len(children): |
| | raise ValueError( |
| | "names does not match length of child elements in xpath." |
| | ) |
| | else: |
| | raise TypeError( |
| | f"{type(self.names).__name__} is not a valid type for names" |
| | ) |
| |
|
| | def _parse_doc( |
| | self, raw_doc: FilePath | ReadBuffer[bytes] | ReadBuffer[str] |
| | ) -> Element: |
| | from xml.etree.ElementTree import ( |
| | XMLParser, |
| | parse, |
| | ) |
| |
|
| | handle_data = get_data_from_filepath( |
| | filepath_or_buffer=raw_doc, |
| | encoding=self.encoding, |
| | compression=self.compression, |
| | storage_options=self.storage_options, |
| | ) |
| |
|
| | with preprocess_data(handle_data) as xml_data: |
| | curr_parser = XMLParser(encoding=self.encoding) |
| | document = parse(xml_data, parser=curr_parser) |
| |
|
| | return document.getroot() |
| |
|
| |
|
| | class _LxmlFrameParser(_XMLFrameParser): |
| | """ |
| | Internal class to parse XML into DataFrames with third-party |
| | full-featured XML library, `lxml`, that supports |
| | XPath 1.0 and XSLT 1.0. |
| | """ |
| |
|
| | def parse_data(self) -> list[dict[str, str | None]]: |
| | """ |
| | Parse xml data. |
| | |
| | This method will call the other internal methods to |
| | validate xpath, names, optionally parse and run XSLT, |
| | and parse original or transformed XML and return specific nodes. |
| | """ |
| | from lxml.etree import iterparse |
| |
|
| | if self.iterparse is None: |
| | self.xml_doc = self._parse_doc(self.path_or_buffer) |
| |
|
| | if self.stylesheet: |
| | self.xsl_doc = self._parse_doc(self.stylesheet) |
| | self.xml_doc = self._transform_doc() |
| |
|
| | elems = self._validate_path() |
| |
|
| | self._validate_names() |
| |
|
| | xml_dicts: list[dict[str, str | None]] = ( |
| | self._parse_nodes(elems) |
| | if self.iterparse is None |
| | else self._iterparse_nodes(iterparse) |
| | ) |
| |
|
| | return xml_dicts |
| |
|
| | def _validate_path(self) -> list[Any]: |
| | msg = ( |
| | "xpath does not return any nodes or attributes. " |
| | "Be sure to specify in `xpath` the parent nodes of " |
| | "children and attributes to parse. " |
| | "If document uses namespaces denoted with " |
| | "xmlns, be sure to define namespaces and " |
| | "use them in xpath." |
| | ) |
| |
|
| | elems = self.xml_doc.xpath(self.xpath, namespaces=self.namespaces) |
| | children = [ch for el in elems for ch in el.xpath("*")] |
| | attrs = {k: v for el in elems for k, v in el.attrib.items()} |
| |
|
| | if elems == []: |
| | raise ValueError(msg) |
| |
|
| | if elems != []: |
| | if self.elems_only and children == []: |
| | raise ValueError(msg) |
| | if self.attrs_only and attrs == {}: |
| | raise ValueError(msg) |
| | if children == [] and attrs == {}: |
| | raise ValueError(msg) |
| |
|
| | return elems |
| |
|
| | def _validate_names(self) -> None: |
| | children: list[Any] |
| |
|
| | if self.names: |
| | if self.iterparse: |
| | children = self.iterparse[next(iter(self.iterparse))] |
| | else: |
| | children = self.xml_doc.xpath( |
| | self.xpath + "[1]/*", namespaces=self.namespaces |
| | ) |
| |
|
| | if is_list_like(self.names): |
| | if len(self.names) < len(children): |
| | raise ValueError( |
| | "names does not match length of child elements in xpath." |
| | ) |
| | else: |
| | raise TypeError( |
| | f"{type(self.names).__name__} is not a valid type for names" |
| | ) |
| |
|
| | def _parse_doc( |
| | self, raw_doc: FilePath | ReadBuffer[bytes] | ReadBuffer[str] |
| | ) -> etree._Element: |
| | from lxml.etree import ( |
| | XMLParser, |
| | fromstring, |
| | parse, |
| | ) |
| |
|
| | handle_data = get_data_from_filepath( |
| | filepath_or_buffer=raw_doc, |
| | encoding=self.encoding, |
| | compression=self.compression, |
| | storage_options=self.storage_options, |
| | ) |
| |
|
| | with preprocess_data(handle_data) as xml_data: |
| | curr_parser = XMLParser(encoding=self.encoding) |
| |
|
| | if isinstance(xml_data, io.StringIO): |
| | if self.encoding is None: |
| | raise TypeError( |
| | "Can not pass encoding None when input is StringIO." |
| | ) |
| |
|
| | document = fromstring( |
| | xml_data.getvalue().encode(self.encoding), parser=curr_parser |
| | ) |
| | else: |
| | document = parse(xml_data, parser=curr_parser) |
| |
|
| | return document |
| |
|
| | def _transform_doc(self) -> etree._XSLTResultTree: |
| | """ |
| | Transform original tree using stylesheet. |
| | |
| | This method will transform original xml using XSLT script into |
| | am ideally flatter xml document for easier parsing and migration |
| | to Data Frame. |
| | """ |
| | from lxml.etree import XSLT |
| |
|
| | transformer = XSLT(self.xsl_doc) |
| | new_doc = transformer(self.xml_doc) |
| |
|
| | return new_doc |
| |
|
| |
|
| | def get_data_from_filepath( |
| | filepath_or_buffer: FilePath | bytes | ReadBuffer[bytes] | ReadBuffer[str], |
| | encoding: str | None, |
| | compression: CompressionOptions, |
| | storage_options: StorageOptions, |
| | ) -> str | bytes | ReadBuffer[bytes] | ReadBuffer[str]: |
| | """ |
| | Extract raw XML data. |
| | |
| | The method accepts three input types: |
| | 1. filepath (string-like) |
| | 2. file-like object (e.g. open file object, StringIO) |
| | 3. XML string or bytes |
| | |
| | This method turns (1) into (2) to simplify the rest of the processing. |
| | It returns input types (2) and (3) unchanged. |
| | """ |
| | if not isinstance(filepath_or_buffer, bytes): |
| | filepath_or_buffer = stringify_path(filepath_or_buffer) |
| |
|
| | if ( |
| | isinstance(filepath_or_buffer, str) |
| | and not filepath_or_buffer.startswith(("<?xml", "<")) |
| | ) and ( |
| | not isinstance(filepath_or_buffer, str) |
| | or is_url(filepath_or_buffer) |
| | or is_fsspec_url(filepath_or_buffer) |
| | or file_exists(filepath_or_buffer) |
| | ): |
| | with get_handle( |
| | filepath_or_buffer, |
| | "r", |
| | encoding=encoding, |
| | compression=compression, |
| | storage_options=storage_options, |
| | ) as handle_obj: |
| | filepath_or_buffer = ( |
| | handle_obj.handle.read() |
| | if hasattr(handle_obj.handle, "read") |
| | else handle_obj.handle |
| | ) |
| |
|
| | return filepath_or_buffer |
| |
|
| |
|
| | def preprocess_data(data) -> io.StringIO | io.BytesIO: |
| | """ |
| | Convert extracted raw data. |
| | |
| | This method will return underlying data of extracted XML content. |
| | The data either has a `read` attribute (e.g. a file object or a |
| | StringIO/BytesIO) or is a string or bytes that is an XML document. |
| | """ |
| |
|
| | if isinstance(data, str): |
| | data = io.StringIO(data) |
| |
|
| | elif isinstance(data, bytes): |
| | data = io.BytesIO(data) |
| |
|
| | return data |
| |
|
| |
|
| | def _data_to_frame(data, **kwargs) -> DataFrame: |
| | """ |
| | Convert parsed data to Data Frame. |
| | |
| | This method will bind xml dictionary data of keys and values |
| | into named columns of Data Frame using the built-in TextParser |
| | class that build Data Frame and infers specific dtypes. |
| | """ |
| |
|
| | tags = next(iter(data)) |
| | nodes = [list(d.values()) for d in data] |
| |
|
| | try: |
| | with TextParser(nodes, names=tags, **kwargs) as tp: |
| | return tp.read() |
| | except ParserError: |
| | raise ParserError( |
| | "XML document may be too complex for import. " |
| | "Try to flatten document and use distinct " |
| | "element and attribute names." |
| | ) |
| |
|
| |
|
| | def _parse( |
| | path_or_buffer: FilePath | ReadBuffer[bytes] | ReadBuffer[str], |
| | xpath: str, |
| | namespaces: dict[str, str] | None, |
| | elems_only: bool, |
| | attrs_only: bool, |
| | names: Sequence[str] | None, |
| | dtype: DtypeArg | None, |
| | converters: ConvertersArg | None, |
| | parse_dates: ParseDatesArg | None, |
| | encoding: str | None, |
| | parser: XMLParsers, |
| | stylesheet: FilePath | ReadBuffer[bytes] | ReadBuffer[str] | None, |
| | iterparse: dict[str, list[str]] | None, |
| | compression: CompressionOptions, |
| | storage_options: StorageOptions, |
| | dtype_backend: DtypeBackend | lib.NoDefault = lib.no_default, |
| | **kwargs, |
| | ) -> DataFrame: |
| | """ |
| | Call internal parsers. |
| | |
| | This method will conditionally call internal parsers: |
| | LxmlFrameParser and/or EtreeParser. |
| | |
| | Raises |
| | ------ |
| | ImportError |
| | * If lxml is not installed if selected as parser. |
| | |
| | ValueError |
| | * If parser is not lxml or etree. |
| | """ |
| |
|
| | p: _EtreeFrameParser | _LxmlFrameParser |
| |
|
| | if parser == "lxml": |
| | lxml = import_optional_dependency("lxml.etree", errors="ignore") |
| |
|
| | if lxml is not None: |
| | p = _LxmlFrameParser( |
| | path_or_buffer, |
| | xpath, |
| | namespaces, |
| | elems_only, |
| | attrs_only, |
| | names, |
| | dtype, |
| | converters, |
| | parse_dates, |
| | encoding, |
| | stylesheet, |
| | iterparse, |
| | compression, |
| | storage_options, |
| | ) |
| | else: |
| | raise ImportError("lxml not found, please install or use the etree parser.") |
| |
|
| | elif parser == "etree": |
| | p = _EtreeFrameParser( |
| | path_or_buffer, |
| | xpath, |
| | namespaces, |
| | elems_only, |
| | attrs_only, |
| | names, |
| | dtype, |
| | converters, |
| | parse_dates, |
| | encoding, |
| | stylesheet, |
| | iterparse, |
| | compression, |
| | storage_options, |
| | ) |
| | else: |
| | raise ValueError("Values for parser can only be lxml or etree.") |
| |
|
| | data_dicts = p.parse_data() |
| |
|
| | return _data_to_frame( |
| | data=data_dicts, |
| | dtype=dtype, |
| | converters=converters, |
| | parse_dates=parse_dates, |
| | dtype_backend=dtype_backend, |
| | **kwargs, |
| | ) |
| |
|
| |
|
| | @doc( |
| | storage_options=_shared_docs["storage_options"], |
| | decompression_options=_shared_docs["decompression_options"] % "path_or_buffer", |
| | ) |
| | def read_xml( |
| | path_or_buffer: FilePath | ReadBuffer[bytes] | ReadBuffer[str], |
| | *, |
| | xpath: str = "./*", |
| | namespaces: dict[str, str] | None = None, |
| | elems_only: bool = False, |
| | attrs_only: bool = False, |
| | names: Sequence[str] | None = None, |
| | dtype: DtypeArg | None = None, |
| | converters: ConvertersArg | None = None, |
| | parse_dates: ParseDatesArg | None = None, |
| | |
| | encoding: str | None = "utf-8", |
| | parser: XMLParsers = "lxml", |
| | stylesheet: FilePath | ReadBuffer[bytes] | ReadBuffer[str] | None = None, |
| | iterparse: dict[str, list[str]] | None = None, |
| | compression: CompressionOptions = "infer", |
| | storage_options: StorageOptions = None, |
| | dtype_backend: DtypeBackend | lib.NoDefault = lib.no_default, |
| | ) -> DataFrame: |
| | r""" |
| | Read XML document into a ``DataFrame`` object. |
| | |
| | .. versionadded:: 1.3.0 |
| | |
| | Parameters |
| | ---------- |
| | path_or_buffer : str, path object, or file-like object |
| | String, path object (implementing ``os.PathLike[str]``), or file-like |
| | object implementing a ``read()`` function. The string can be any valid XML |
| | string or a path. The string can further be a URL. Valid URL schemes |
| | include http, ftp, s3, and file. |
| | |
| | xpath : str, optional, default './\*' |
| | The XPath to parse required set of nodes for migration to DataFrame. |
| | XPath should return a collection of elements and not a single |
| | element. Note: The ``etree`` parser supports limited XPath |
| | expressions. For more complex XPath, use ``lxml`` which requires |
| | installation. |
| | |
| | namespaces : dict, optional |
| | The namespaces defined in XML document as dicts with key being |
| | namespace prefix and value the URI. There is no need to include all |
| | namespaces in XML, only the ones used in ``xpath`` expression. |
| | Note: if XML document uses default namespace denoted as |
| | `xmlns='<URI>'` without a prefix, you must assign any temporary |
| | namespace prefix such as 'doc' to the URI in order to parse |
| | underlying nodes and/or attributes. For example, :: |
| | |
| | namespaces = {{"doc": "https://example.com"}} |
| | |
| | elems_only : bool, optional, default False |
| | Parse only the child elements at the specified ``xpath``. By default, |
| | all child elements and non-empty text nodes are returned. |
| | |
| | attrs_only : bool, optional, default False |
| | Parse only the attributes at the specified ``xpath``. |
| | By default, all attributes are returned. |
| | |
| | names : list-like, optional |
| | Column names for DataFrame of parsed XML data. Use this parameter to |
| | rename original element names and distinguish same named elements and |
| | attributes. |
| | |
| | dtype : Type name or dict of column -> type, optional |
| | Data type for data or columns. E.g. {{'a': np.float64, 'b': np.int32, |
| | 'c': 'Int64'}} |
| | Use `str` or `object` together with suitable `na_values` settings |
| | to preserve and not interpret dtype. |
| | If converters are specified, they will be applied INSTEAD |
| | of dtype conversion. |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | converters : dict, optional |
| | Dict of functions for converting values in certain columns. Keys can either |
| | be integers or column labels. |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | parse_dates : bool or list of int or names or list of lists or dict, default False |
| | Identifiers to parse index or columns to datetime. The behavior is as follows: |
| | |
| | * boolean. If True -> try parsing the index. |
| | * list of int or names. e.g. If [1, 2, 3] -> try parsing columns 1, 2, 3 |
| | each as a separate date column. |
| | * list of lists. e.g. If [[1, 3]] -> combine columns 1 and 3 and parse as |
| | a single date column. |
| | * dict, e.g. {{'foo' : [1, 3]}} -> parse columns 1, 3 as date and call |
| | result 'foo' |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | encoding : str, optional, default 'utf-8' |
| | Encoding of XML document. |
| | |
| | parser : {{'lxml','etree'}}, default 'lxml' |
| | Parser module to use for retrieval of data. Only 'lxml' and |
| | 'etree' are supported. With 'lxml' more complex XPath searches |
| | and ability to use XSLT stylesheet are supported. |
| | |
| | stylesheet : str, path object or file-like object |
| | A URL, file-like object, or a raw string containing an XSLT script. |
| | This stylesheet should flatten complex, deeply nested XML documents |
| | for easier parsing. To use this feature you must have ``lxml`` module |
| | installed and specify 'lxml' as ``parser``. The ``xpath`` must |
| | reference nodes of transformed XML document generated after XSLT |
| | transformation and not the original XML document. Only XSLT 1.0 |
| | scripts and not later versions is currently supported. |
| | |
| | iterparse : dict, optional |
| | The nodes or attributes to retrieve in iterparsing of XML document |
| | as a dict with key being the name of repeating element and value being |
| | list of elements or attribute names that are descendants of the repeated |
| | element. Note: If this option is used, it will replace ``xpath`` parsing |
| | and unlike xpath, descendants do not need to relate to each other but can |
| | exist any where in document under the repeating element. This memory- |
| | efficient method should be used for very large XML files (500MB, 1GB, or 5GB+). |
| | For example, :: |
| | |
| | iterparse = {{"row_element": ["child_elem", "attr", "grandchild_elem"]}} |
| | |
| | .. versionadded:: 1.5.0 |
| | |
| | {decompression_options} |
| | |
| | .. versionchanged:: 1.4.0 Zstandard support. |
| | |
| | {storage_options} |
| | |
| | dtype_backend : {{"numpy_nullable", "pyarrow"}}, defaults to NumPy backed DataFrames |
| | Which dtype_backend to use, e.g. whether a DataFrame should have NumPy |
| | arrays, nullable dtypes are used for all dtypes that have a nullable |
| | implementation when "numpy_nullable" is set, pyarrow is used for all |
| | dtypes if "pyarrow" is set. |
| | |
| | The dtype_backends are still experimential. |
| | |
| | .. versionadded:: 2.0 |
| | |
| | Returns |
| | ------- |
| | df |
| | A DataFrame. |
| | |
| | See Also |
| | -------- |
| | read_json : Convert a JSON string to pandas object. |
| | read_html : Read HTML tables into a list of DataFrame objects. |
| | |
| | Notes |
| | ----- |
| | This method is best designed to import shallow XML documents in |
| | following format which is the ideal fit for the two-dimensions of a |
| | ``DataFrame`` (row by column). :: |
| | |
| | <root> |
| | <row> |
| | <column1>data</column1> |
| | <column2>data</column2> |
| | <column3>data</column3> |
| | ... |
| | </row> |
| | <row> |
| | ... |
| | </row> |
| | ... |
| | </root> |
| | |
| | As a file format, XML documents can be designed any way including |
| | layout of elements and attributes as long as it conforms to W3C |
| | specifications. Therefore, this method is a convenience handler for |
| | a specific flatter design and not all possible XML structures. |
| | |
| | However, for more complex XML documents, ``stylesheet`` allows you to |
| | temporarily redesign original document with XSLT (a special purpose |
| | language) for a flatter version for migration to a DataFrame. |
| | |
| | This function will *always* return a single :class:`DataFrame` or raise |
| | exceptions due to issues with XML document, ``xpath``, or other |
| | parameters. |
| | |
| | See the :ref:`read_xml documentation in the IO section of the docs |
| | <io.read_xml>` for more information in using this method to parse XML |
| | files to DataFrames. |
| | |
| | Examples |
| | -------- |
| | >>> xml = '''<?xml version='1.0' encoding='utf-8'?> |
| | ... <data xmlns="http://example.com"> |
| | ... <row> |
| | ... <shape>square</shape> |
| | ... <degrees>360</degrees> |
| | ... <sides>4.0</sides> |
| | ... </row> |
| | ... <row> |
| | ... <shape>circle</shape> |
| | ... <degrees>360</degrees> |
| | ... <sides/> |
| | ... </row> |
| | ... <row> |
| | ... <shape>triangle</shape> |
| | ... <degrees>180</degrees> |
| | ... <sides>3.0</sides> |
| | ... </row> |
| | ... </data>''' |
| | |
| | >>> df = pd.read_xml(xml) |
| | >>> df |
| | shape degrees sides |
| | 0 square 360 4.0 |
| | 1 circle 360 NaN |
| | 2 triangle 180 3.0 |
| | |
| | >>> xml = '''<?xml version='1.0' encoding='utf-8'?> |
| | ... <data> |
| | ... <row shape="square" degrees="360" sides="4.0"/> |
| | ... <row shape="circle" degrees="360"/> |
| | ... <row shape="triangle" degrees="180" sides="3.0"/> |
| | ... </data>''' |
| | |
| | >>> df = pd.read_xml(xml, xpath=".//row") |
| | >>> df |
| | shape degrees sides |
| | 0 square 360 4.0 |
| | 1 circle 360 NaN |
| | 2 triangle 180 3.0 |
| | |
| | >>> xml = '''<?xml version='1.0' encoding='utf-8'?> |
| | ... <doc:data xmlns:doc="https://example.com"> |
| | ... <doc:row> |
| | ... <doc:shape>square</doc:shape> |
| | ... <doc:degrees>360</doc:degrees> |
| | ... <doc:sides>4.0</doc:sides> |
| | ... </doc:row> |
| | ... <doc:row> |
| | ... <doc:shape>circle</doc:shape> |
| | ... <doc:degrees>360</doc:degrees> |
| | ... <doc:sides/> |
| | ... </doc:row> |
| | ... <doc:row> |
| | ... <doc:shape>triangle</doc:shape> |
| | ... <doc:degrees>180</doc:degrees> |
| | ... <doc:sides>3.0</doc:sides> |
| | ... </doc:row> |
| | ... </doc:data>''' |
| | |
| | >>> df = pd.read_xml(xml, |
| | ... xpath="//doc:row", |
| | ... namespaces={{"doc": "https://example.com"}}) |
| | >>> df |
| | shape degrees sides |
| | 0 square 360 4.0 |
| | 1 circle 360 NaN |
| | 2 triangle 180 3.0 |
| | """ |
| | check_dtype_backend(dtype_backend) |
| |
|
| | return _parse( |
| | path_or_buffer=path_or_buffer, |
| | xpath=xpath, |
| | namespaces=namespaces, |
| | elems_only=elems_only, |
| | attrs_only=attrs_only, |
| | names=names, |
| | dtype=dtype, |
| | converters=converters, |
| | parse_dates=parse_dates, |
| | encoding=encoding, |
| | parser=parser, |
| | stylesheet=stylesheet, |
| | iterparse=iterparse, |
| | compression=compression, |
| | storage_options=storage_options, |
| | dtype_backend=dtype_backend, |
| | ) |
| |
|