dotcat-parser

TypeScript library for parsing Spanish Cadastre .CAT fixed-width exchange files.

This project is just starting. The current focus is:

• keeping a local copy of the official CAT format specification;
• defining machine-readable record schemas;
• building a streaming parser for 1000-character fixed-width records;
• exposing JSON/NDJSON/CSV-friendly outputs.

See SPEC.md for the first implementation target.

Local Spec

The official CAT format reference lives under docs/spec/.

Planned API

parseLine(line)
parseFile(path)
parseStream(stream)
validateFile(file)

Streaming Usage

import { parseStream } from "dotcat-parser";

const stream = Bun.file("15001U_23012026.CAT").stream();

for await (const record of parseStream(stream)) {
  console.log(record.type, record.name);
}

parseStream reads the file sequentially and yields one parsed CAT record at a time, so callers do not need to load the whole file into memory.

Status

Pre-alpha. APIs and schemas are not stable yet.

License

Source code is licensed under AGPL-3.0-or-later.

This license applies to the code in this repository. It does not grant rights to private datasets, production databases, API credentials, hosted services, domains, trademarks, logos, or commercial agreements.