This is an implementation of the Lucene Query Parser developed using PEG.js.
A quick example of how to use it:
var parser = require('lucene-query-parser');
// 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']); // goA slightly more complicated example:
var parser = require('lucene-query-parser');
// 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']); // barFor more detailed docs, check out the wiki.
The library is available as an npm module.
To install, run:
npm install lucene-query-parser
In the browser, use RequireJS to load the AMD compatible module. In the example below, it assumes there's a ~/vendor directory for third-party libraries, with RequireJS in ~/vendor/requirejs/require.js and our library in ~/vendor/lucene-query-parser/lucene-query-parser.js.
<!DOCTYPE html>
<html>
<head>
<!-- RequireJS -->
<script type="text/javascript" src="vendor/requirejs/require.js"></script>
<!-- RequireJS -->
<script type="text/javascript">
require.config({
baseUrl: './vendor/lucene-query-parser/'
});
require(['lucene-query-parser.js'], function(lucenequeryparser) {
// Use the Lucene Query Parser library here
var results = lucenequeryparser.parse('example: query');
console.log(results);
});
</script>
</head>
<body>
<!-- ... -->
</body>
</html>Unit tests are built with Jasmine.
To run the unit tests on the command-line, using node:
npm test
To run the unit tests, just open SpecRunner.html in any browser.
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 arbitrary query and see what the results will be like or debug a problem with the parser for a given piece of data.
If you'd like to help out with the project, or if you have a question, feel free to contact Troy Howard at [email protected].
Bug reports or feature requests should go in the GitHub issue tracker. Please include relevant sample data (the query) and a good description of the challenges you're facing.
Look to the wiki for additional documentation and other resources.