Enketo Transformer

NodeJS library that transforms OpenRosa/ODK XForms into a format the Enketo understands. It works both as a library module, as well as a standalone app.

Prerequisites

1. nodeJS 6+ and npm (only tested on Ubuntu 14.04, on older distros the GCC compiler may not be recent enough)

Install as module

npm install enketo-transformer --save

Use as module

const transformer = require('enketo-transformer');
const xform = fs.readFileSync( 'path/to/xform.xml' );
  
transformer.transform( {
    // required string of XForm
    xform: xform,
    // optional string, to add theme if no theme is defined in the XForm
    theme: 'sometheme', 
    // optional map, to replace jr://..../myfile.png URLs
    media: {
        'myfile.png' : '/path/to/somefile.png',
        'myfile.mp3' : '/another/path/to/2.mp3'
    },
    // optional ability to disable markdown rendering (default is true)
    markdown: false,
    // optional preprocess function that transforms the XForm (as libXMLJs object) to 
    // e.g. correct incompatible XForm syntax before Enketo's transformation takes place 
    preprocess: doc => doc,
} ).then(function( result ){
    // do something with result
});

Install as app (web API)

1. clone repo
2. install dependencies with npm install

Use as app (web API)

1. start with npm start
2. limited use with GET /transform with xform parameter (required, xform URL), or
3. full-featured use with: POST /transform with URL-encoded body including xform (required, full XForm as a string), theme (optional, string), and media (optional, map) parameters

sample GET request:

curl http://localhost:8085/transform?xform=https://example.com/forms/78372/form.xml

sample POST request:

curl -d "xform=<xform>x</xform>&theme=plain&media[myfile.png]=/path/to/somefile.png&media[this]=that" http://localhost:8085/transform

Response format

{
    "form" : "<form>.....</form>",
    "model": "<model>...</model>",
    "transformerVersion": "1.13.0",
    "languageMap": { "Français": "fr", "English": "en" }
}
    

Test

• run tests with npm test

Develop

The script npm run develop runs the app on port 8085 and also serves test/forms on port 8081. You could test the transformation output by placing an XForm in test/forms and running http://localhost:8085/transform?xform=http://localhost:8081/autocomplete.xml

A vagrant configuration file and provisioning script is also included. Use DEBUG environment variable to see debug terminal output, e.g.:

DEBUG=api,transformer,markdown,language node app.js

License

See license document. Also note the additional 'powered by enketo' footer requirement of enketo-xslt which is used in this repository and therefore applicable.

Change Log

See change log