Application Metadata

Applications commonly need to pass data to the front end which is not either clinical data about a patient or episode of care, or coded reference data.

Opal provides a simple API for working with such data via the opal.core.metadata.Metadata discoverable.

metadata is made available on the scopes for patient lists and patient details

Defining Metadata

Defining metadata uses the same pattern as all discoverable features, we define a subclass:

from django.conf import settings
from opal.core import metadata

class FavouriteColours(metadata.Metadata):
    slug = 'favourite-colour'

    def to_dict(klass, **kwargs):
        return {'favourite_colour': settings.FAVOURITE_COLOUR}

The to_dict method will be passed the current user as a keyword argument.

Accessing Metadata on the front end

We can access our metadata with the Angular Metadata service.

// yourapp/routes.js
when('/my/route', {
    controller: 'MyCtrl',
    resolve: {
           metadata: function(Metadata){ return Metadata; }

// yourapp/yourctrl.js
    'MyCtrl', function($scope, metadata){

      $scope.favourite_colour = metadata.favourite_colour;
      // -> Whatever settings.FAVOURITE_COLOUR is set to