TypesXLIFF

TypesXLIFF is a TypeScript / Node.js library for parsing, generating, and validating XLIFF 2.x files (2.0, 2.1 and 2.2). It includes a fully typed object model and JSON conversion for processing translation and localization data.

Quick example

Load an XLIFF file and read the first source segment:

import { XliffParser } from "typesxliff";

const parser = new XliffParser();
parser.parseFile("file.xlf");

const doc = parser.getXliffDocument();
const segment = doc?.getFiles()?.[0]?.getEntries()?.[0];

if (segment && "getItems" in segment) {
    console.log(segment.getItems()[0]?.getSource()?.getContent().join(""));
}

Why TypesXLIFF

• Full XLIFF 2.x object model (not just parsing)
• Type-safe API for building and modifying documents
• JSON round-trip for integration with other systems
• Built on TypesXML (streaming XML parser with validation support)

Features

• Parse XLIFF files — Load an existing XLIFF 2.x file into a fully typed object model using XliffParser
• Build programmatically — Construct XliffDocument instances from scratch using the provided model classes
• Write XLIFF files — Serialize any XliffDocument back to a well-formed XML file using XliffDocument.writeDocument()
• JSON round-trip — Convert XLIFF ⇄ JSON (lossless) using XliffToJson, and reconstruct it back using JsonToXliff. Built on the round-trip JSON conversion provided by TypesXML
• Validate — Each model element exposes an isValid() method that checks structural and semantic constraints against the XLIFF 2.x specification

Use cases

• Parse XLIFF 2.x files in Node.js or TypeScript
• Generate XLIFF documents programmatically
• Convert XLIFF to/from JSON
• Validate XLIFF structure and content
• Extract terminology and bilingual term pairs from XLIFF content
• Build localization or translation pipelines

Documentation

• Getting Started
• Parsing XLIFF Files
• Building XLIFF Documents
• JSON Conversion
• XLIFF Validation Example - Companion command-line tool for strict XML Schema validation and end-to-end validation workflows. TypesXLIFF provides the object model and semantic validation methods used by that project.
• TypesTerms - Companion library and command-line tool for extracting term candidates (monolingual) and bilingual translation pairs from XLIFF files using the YAKE algorithm. Built on top of TypesXLIFF for XLIFF parsing and object model access.

Scope

TypesXLIFF provides type-safe classes for building, parsing, and serializing XLIFF documents. It covers:

• XLIFF versions: 2.0, 2.1 and 2.2
• Core structural elements: <xliff>, <file>, <skeleton>, <group>, <unit>, <segment>, <ignorable>, <notes>, <note>, <originalData>, <data>, <source> and <target>
• Inline elements: <cp>, <ph>, <pc>, <sc>, <ec>, <mrk>, <sm> and <em>
• Metadata module: <metadata>, <metaGroup> and <meta>
• Translation Candidates module: <matches> and <match>
• Glossary module: <glossary>, <glossEntry>, <term>, <translation> and <definition>

Each class includes validation (isValid()) and XML serialization (toElement()) methods.

Parsing an existing XLIFF file

import { Catalog } from "typesxml";
import { XliffParser, XliffDocument } from "typesxliff";

const parser = new XliffParser();
// Using a catalog is optional. When provided, the SAX parser can resolve grammar
// schemas and populate default attribute values declared in them.
// A sample catalog covering XLIFF 2.0, 2.1 and 2.2 is included in the catalog/ folder.
parser.setCatalog(new Catalog('/path/to/typesxliff/catalog/catalog.xml'));
parser.parseFile('/path/to/file.xlf');
const doc: XliffDocument | undefined = parser.getXliffDocument();

Building and writing an XLIFF document

import { XliffDocument, XliffFile, XliffUnit, XliffSegment, XliffSource } from "typesxliff";

const doc = new XliffDocument("2.1", "en", "es");

const file = new XliffFile("f1");
const unit = new XliffUnit("u1");
const segment = new XliffSegment("s1");
const source = new XliffSource();
source.addText("Hello, world!");
segment.setSource(source);
unit.addSegment(segment);
file.addUnit(unit);
doc.addFile(file);

doc.writeDocument('/path/to/output.xlf', true);

Dependencies

• TypesXML — XML object model and SAX parser
• TypesBCP47 — BCP 47 language tag utilities

Installation

npm install typesxliff

Building from Source

npm install
npm run build