pip-requirements-js

A pure JavaScript/TypeScript parser for pip requirements files. Process requirements.txt, constraints.txt, or pip-tools' requirements.in – all without ever leaving JavaScript.

pip-requirements-js strictly adheres to pip's documentation of the requirements file format, along with PEP 508 – Dependency specification for Python Software Packages. You can sleep well knowing that no dependency will be misinterpreted (if that ever keeps you up at night).

API

To extract all the requirements from a given file, use

parsePipRequirementsFile(fileContent: string): Requirement[]

To extract a requirement from a given line, use

parsePipRequirementsLine(lineContent: string): Requirement | null

(note that null will be returned if the line is empty)

In both cases a RequirementsSyntaxError will be thrown if the provided content contains invalid syntax.

To make use of the resulting data, look up what Requirement is made up of in types.ts.

Internals

pip-requirements-js is built with the robust parser generator Ohm.js – the core of this library is the pep-508.ohm grammar, which is an Ohm port of PEP 508's complete dependency specification grammar (originally defined for Parsley), with some pip-specific additions (such as the -r extra-requirements.txt syntax). This ensures the greatest possible compatibility with what pip itself does.