xml-validator 1.1.1

High-performance XML lexical structure validator using DFA state machine.

xml_validator

A high-performance C++/Cython module for rapidly checking the well-formedness of XML documents.

Features

• Performance: Written in Cython with direct C/C++ access for maximum processing speed.
• Low-level Processing: Operates directly on byte streams, minimizing overhead.
• No Dependencies: Does not require libxml2 or other external XML parsers.
• GIL-Free: The core validation logic runs without the Global Interpreter Lock (GIL), allowing for efficient use in multi-threaded applications.

Installation

pip install xml_validator

API and Usage

The module provides two primary functions.

---

is_malformed_xml(content: bytes) -> bool

Checks the well-formedness of XML provided as a byte string.

• Parameters:
  • content (bytes): A byte string or any object that supports the buffer protocol (e.g., bytearray, memoryview) containing the XML content.
• Returns:
  • bool: True if the XML document is malformed. False if the document is well-formed.

Example:

from xml_validator import is_malformed_xml

# Well-formed XML
good_xml = b'<?xml version="1.0"?><root><item/></root>'
assert is_malformed_xml(good_xml) is False

# Malformed XML (unclosed tag)
bad_xml = b'<root><item>'
assert is_malformed_xml(bad_xml) is True

# Malformed XML (incorrect nesting)
bad_xml_nesting = b'<root><item></root></item>'
assert is_malformed_xml(bad_xml_nesting) is True

---

is_malformed_xml_file(path: str) -> bool

Checks the well-formedness of an XML document by reading it from a file.

• Parameters:
  • path (str): The path to the file.
• Returns:
  • bool: True if the file does not exist, cannot be read, or contains malformed XML. False if the document in the file is well-formed.

Example:

from xml_validator import is_malformed_xml_file

# Create test files
with open("good.xml", "wb") as f:
    f.write(b'<data><node value="1" /></data>')

with open("bad.xml", "wb") as f:
    f.write(b'<data><node value="1"')

# Perform checks
assert is_malformed_xml_file("good.xml") is False
assert is_malformed_xml_file("bad.xml") is True
assert is_malformed_xml_file("non_existent_file.xml") is True

---

Benchmark

Performance comparison against the standard lxml library. The benchmark highlights significant speed improvements, particularly in identifying malformed documents early.

Scenario	lxml (ms)	xml_validator (ms)	Speedup
Small Valid XML	0.003	0.001	5.12× faster
Large Valid XML (10k records)	14.768	3.975	3.72× faster
Invalid XML (unclosed tag)	0.0065	0.0003	19.92× faster

License

The MIT License Copyright (c) 2023 Rahul Sharma