xq-rhino

Javascript CommonJs implementation for XQuery 3.1 leveraging the Rhino Javascript library.

Why?

Use javascript in XQuery scripts and services or test new javascript npm module with XQuery! Additionally, with the prevlelance of node.js in resent years. Algorithms and libraries exist in the node space that would be a shame to not use in your next XQuery project.

Installation

Copy the xq-rhino-x.jar into your basex\lib directory

Or use xqpm to do it for you:

xqpm xq-rhino

Declaration

To use the module in your scripts, import it:

import module namespace js = 'http://xq-rhino';

Version 0.1-BETA

This module is currently in Beta and should be used with caution. Especially in scenarios involving the writing of sensitive data.

Dependencies

This module currently require BaseX

Contribute

If you like what you see, or have any ideas to make it better, feel free to leave feedback, make a pull request, log an issue or simply question ask a question!

Usage

This module is not intended to help write better javascript, but leverage it. The most common use case is loading existing modules and using their functionality in your XQuery and RESTXQ solutions!

For example the following modules have been tested:

• moment.js
• remarkable.js
• mustache.js
• browserfy.js

Let me know if any other module works for you!

Interop

The module, xq-rhino provides a simple mapping between the Rhino Java javascript engine and BaseX. It leverages the new map and array data types introduced in XQuery 3.1.

In order to provide a seamless scripting experience, all script objects are automatically mapped to XQuery objects. This allows for the use of the ? operator when querying objects or arrays:

let $obj := js:new('{
  first: "John", 
  last: "Doe", 
  name: function () { first + ' ' + last;}
')
return
  'His name is ' || $obj?name() || '.'

Additionlly, script objects and XQuery objects are interchangable, including function items. For example, its possible to pass XQuery functions into javascript functions and vice versa:

let $jsFunc := js:new('function (callback) { 
  callback("Hey XQuery!"); 
}')
return
  $jsFunc(trace(?))

This goes the same for maps and arrays.

Methods

The module provides a few helper methods for interacting with javascript objects.

new

New allows for contstruction and execution of any arbitray javascript code. For example, to create an array and then query it with the new XQuery ? operator you could do the following:

let $array := js:new('[1,2,3,4,5,6,7,8]')
return
  $array?2

require

The require method implements the CommonJS pattern as used with Node.js.

For example, if we wanted to load mustache with the node modules stored at /home/user/modules we would do the following:

let $require := js:require('/home/user/modules/')
let $mustache := $require('Mustache')
return
  $mustache?render('Hello {{name}}!', map { 'name': 'world' })

keys

The keys method returns all the keys found in a script object. Operates exactly like map:keys. For example, the following would return: first last

let $obj := js:new('{ first: "John", last: "Doe" }')
return
  js:keys($obj)

get

Get allows an alternative means for the retrieval of script object properties.

let $obj := js:new('{name: "world"}')
return
  js:get($obj, 'name')

let $obj := js:new('{name: "world"}')
return
  $obj?name

put

As the name eludes. Allows for putting a value. For example:

let $obj := js:new('{}')
  => js:put('first', 'John')
  => js:put('last', 'Doe')
return
  $obj?first

remove

Removes a key from a script object:

let $obj := js:new('{first:"John"}')
let $empty := js:remove($obj, 'first')
return 
  $empty

Other Examples

Moment.js

Here is a simple example of loading and using Moment.js.

  let $require := js:require('path/to/modules/dir/')
  let $moment := $require('Moment')
  return
   $moment()?add('-1','day')?fromNow(())

Remarkable.js

And another with Remarkable:

Here is the example in the remarkable page:

var Remarkable = require('remarkable');
var md = new Remarkable();

console.log(md.render('# Remarkable rulezz!'));

And the equivalent with xq-rhino, including the defining of the modules directory.

  let $require := js:require('path/to/modules/dir/')
  let $rm := $require('Remarkable')
  let $md := js:new($rm)
  return 
    $md?render('# Remarkable rulezz! ', ()) => trace()

Unit Tests

Clone the repo and run basex -t within the repo's directory to run the unit tests.

Shout Out!

If you like what you see here please star the repo and follow me on github or linkedIn