lucene-query-parser
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Lucene Query Parser for JavaScript created using PEG.js
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# Lucene Query Parser for JavaScript [](https://travis-ci.org/thoward/lucene-query-parser.js)
This is an implementation of the Lucene Query Parser developed using PEG.js.
## Example
A quick example of how to use it:
```javascript
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']); // go
```
A slightly more complicated example:
```javascript
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']); // bar
```
For more detailed docs, check out [the wiki](https://github.com/thoward/lucene-query-parser.js/wiki).
## Installation
### On the Command-Line
The library is available as an npm module.
To install, run:
```
npm install lucene-query-parser
```
### In the Browser
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`.
```html
<!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
Unit tests are built with [Jasmine](http://pivotal.github.com/jasmine/).
### On the Command-line
To run the unit tests on the command line, using node:
```
npm test
```
### In the Browser
To run the unit tests, just open [SpecRunner.html](https://rawgithub.com/thoward/lucene-query-parser.js/master/spec/SpecRunner.html) in any browser.
## Grammar
The parser is auto-generated from a PEG implementation in JavaScript called [PEG.js](http://pegjs.majda.cz/).
To test the grammar without using the generated parser, or if you want to modify it, try out [PEG.js online](http://pegjs.majda.cz/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.
## Community
If you'd like to help out with the project, or if you have a question, feel free to contact Troy Howard at thoward37@gmail.com.
Bug reports or feature requests should go in the GitHub [issue tracker](https://github.com/thoward/lucene-query-parser.js/issues). Please include relevant sample data (the query) and a good description of the challenges you're facing.
Look to the [wiki](https://github.com/thoward/lucene-query-parser.js/wiki) for additional documentation and other resources.