CustomXMLParser 1.0.1

Python Libary that allows for customized parsing of XML files using a set of configurations. Output is a dictonary. This library builds on the xml2dict library.

Custom XML to Dict Parser

Table of Contents

• Overview
• Library Installalion
• Library Usage
• Config file

Overview

This package allows you to parse XML files. The tool uses the xml2dict package to parse XML files in raw format and returns data as a python dictionary and builds on that to provide custom tailoring of what information to return from the XML file. In other words, with a configuration file, you can return specific data from the XML file in a specific format.

Library Installalion

To install the library simply run the following command in a cmd, shell or whatever...

# It's recommended to create a virtual environment

# Windows
pip install xmlparser

# Linux
pip3 install xmlparser

Library usage?

Example usage

If you wish to read the XML file as is and simply convert it to a python dictionary, then do the following:

from xmlparser import XmlParser

xml_parser = XmlParser(parser_type='raw')
xml_file = 'path_to_xml_file'
xml_dict = xml_parser.parse(xml_file)

If you wish to read specific portions of the XML file and format them in a particular way, then do the following:

from xmlparser import XmlParser

config_file = 'path_to_config_file'
xml_parser = XmlParser(config_file=config_file, parser_type='custom')
xml_file = 'path_to_xml_file'
xml_dict = xml_parser.parse(xml_file)

Note, the XmlParser class uses the following default XML attributes

'''
name_key (str, optional): this is a custom/xml configuration parameter, and it is the name of primary tag. Defaults to "@name".
table_key (str, optional): this is a custom/xml configuration parameter, and it is the table identifier. Defaults to "th".
header_key (str, optional): this is a custom/xml configuration parameter, and it is the header identifier. Defaults to 'header'.
data_key (str, optional): this is a custom/xml configuration parameter, and it is the data identifier. Defaults to "rows".
header_text_key (str, optional): this is a custom/xml configuration parameter, and it is the table's key identifier. Defaults to "#text".
'''

You can override those attributes by passing them to the constructor of the XmlParser class as follows:

from xmlparser import XmlParser

config_file = 'path_to_config_file'
xml_parser = XmlParser(config_file=config_file, parser_type='custom', encoding='utf-8',
                       name_key='<desired_name_key>', table_key='<desired_table_key>', header_key='<desired_header_keyr>',
                       data_key='<desired_data_key>', header_text_key='<desired_header_text_key>')
xml_file = 'path_to_xml_file'
xml_dict = xml_parser.parse(xml_file)

Config file

Below shows an example of configurations for custom parsing of XML.

{
  "TREE":{
    "TABLE_A": {},
    "TABLE_B": {"TABLE_C": {}}
  },

  "TABLE_A":
    [
      "element0_tag,element0_name",
      "element1_tag,element1_name"
    ],
  "TABLE_B":
    [
      "element0_tag*,element1_tag*,element2_tag,element2_name"
    ],
  "TABLE_C":
    [
      "element0_tag,element0_name"
    ]
}

General Rules

• Capitalize all dictionary keys.
• * is wildcard notation: returns data for all available elements

Tree structure

The structure can be flat or nested. If you wish to return child data for a particular parent, then you have to include the child as value for the parent. For example, parent TABLE_B has child TABLE_C. If TABLE_C has a child of its own, then we add it to TABLE_C in the same way.

Data structure

Let's make some assumptions about elements to make this example easy to follow.

• For TABLE_A, assume element0_tag and element1_tag map to table, element0_name to info, and element1_name to metadata.
• For TABLE_B, assume element0_tag maps to container, element1_tag to node, and element2_tag to table, and element2_name to info.
• For TABLE_C, assume element0_tag maps to table and element0_name to images

In the above config example, we are interested in returning data for TABLE_A, TABLE_B, AND TABLE_C. For each key, a path or a list of paths (xpath) is/are required to be provided in order to retrieve data from the XML file. For example:

• TABLE_A has two paths ["table,info", "table,metadata"], data under info and metadata tables will be returned and stored in TABLE_A
• TABLE_B has single path ["container*,node*,table,images"], data under info table for all nodes and all containers will be returned and stored in TABLE_B.
• TABLE_C has single path ["table,images"], data under images table for all parent nodes and containers will be returned and stored in TABLE_C.

Notice, full path isn't required for TABLE_C and the GFC (greatest common factor) between the child TABLE_C and the parent TABLE_B is only required in the parent table. Since TABLE_C is a child of TABLE_B, it falls under the same path, but TABLE_C breaks away at "table,images" and that's why it is the only specified path. In other words, since TABLE_C is a child of TABLE_B, all TABLE_B rules carry over to TABLE_C.

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Author: Hamdan, Muhammad (@mhamdan91 - ©)