README.md

Lucene Query Parser for JavaScript

This is an implementation of the Lucene Query Parser developed using PEG.js.

Example

A quick example of how to use it:

var parser = require('lucene-queryparser');

// return the expression tree
var results = parser.parse('title:"The Right Way" AND text:go');

console.log(results['left']['field']);      // title
console.log(results['left']['term']);       // The Right Way
console.log(results['operator']);           // AND
console.log(results['right']['field']);     // text
console.log(results['right']['term']);      // go

A slightly more complicated example:

var parser = require('lucene-queryparser');

// return the expression tree
var results = parser.parse('test AND (foo OR bar)');

console.log(results['left']['term']);       // test
console.log(results['operator']);           // AND

// the grouped expression in parentheses becomes it's own nested node
var rightNode = results['right'];

console.log(rightNode['left']['term']);     // foo
console.log(rightNode['operator']);         // OR
console.log(rightNode['right']['term']);    // bar

Installation

On the Command-Line

The library is available as an npm module.

To install, run:

npm install lucene-queryparser

Unit Tests

Unit tests are built with Jasmine.

On the Command-line

To run the unit tests on the command line, using node:

npm test

Grammar

The parser is auto-generated from a PEG implementation in Javascript called PEG.js.

To test the grammar without using the generated parser, or if you want to modify it, try out PEG.js online. This is a handy way to test an abritrary query and see what the results will be like or debug a problem with the parser for a given piece of data.