The GEOSS Discovery And Access Broker APIs
Authors: Fabrizio Papeschi, Mattia Santoro, Stefano Nativi
API version: 1.4.3-beta

DAB JavaScript API

In order to simplify the development of applications and clients making use of the DAB, this high level client-side Open APIs (Application Program Interface) have been designed and developed in JavaScript along with this documentation and the following usage examples

See also the RESTful API

Click the button below to download the full minified file which includes also all the required dependencies

Click the button below to download the light minified file which do not includes the required dependencies

Important changes from version 1.2.x

There are some important changes from the previous version 1.2.x. These changes redesigns the API in order to achieve the following goals: In particular there are the following major changes: Users of the previous versions of the API, are invited to update the code of their applications considering in particular the deprecated methods and properties depicted above.

The UI package

The UI package contains a complete set of widget and components which allow to easily create Graphical User interfaces; see here for a complete usage example.

New widgets and components as well as new functionalities for the existing ones are supplied continuously; often check these docs to be always updated!

Getting started

The DAB is modeled in this API by the DAB object which is the API entry point. DAB resources are modeled by nodes whose characteristics are described by a report. Nodes can be expanded to retrieve their content, or discovered to retrieve all the DAB nodes matching the given optional constraints. The following code snippet shows a basic discover example

                            // creates a new DAB instance with the given endpoint
                            var dab = GIAPI.DAB('');
                            // defines discover response callback function
                            var onResponse = function(response){
                            	// retrieves the result set
                            	// only one result set is expected (discover not expanded)     
                                var resultSet = response[0];
                            	     document.writeln("Error occurred: "+resultSet.error); 
                                // retrieves the paginator   
                                var paginator = resultSet.paginator;
                                // prints the result set
                                document.writeln("<h3>- Result set -</h3>");
                                // the current paginator page (the first of the result set)    
                                var page =;
                                // printing page nodes
                                document.writeln("<h3>- Nodes of first result set page-</h3>"); 
                                    // retrieving the next page node
                                    var node =;
                                    // retrieving the node report
                                    var report =;     
                            // discover constraints
                            var constraints = {
                                "where": {
                                    "south": 40,
                                    "west": -3,
                                    "north": 46,
                                    "east": 26
                                 "when": {
                                     "from": "2000-01-01",
                                     "to": "2013-01-01"
                                 "what": "temperature"               
                            // set page size
                            var options = {
                                "pageSize": 5           
                            // start discover
                  , constraints, options);
Brokered sources are modeled by DABSource objects, a specialized type of node with the ability to be included or excluded from the discover.

Semantics-enrichment is modeled with the discover extension option which allows to retrieve more than one result set, one for each concept derived from the extension.

Access of resources is done by means of the GINode accessOptions and GINode accessLink methods.

API Usage Examples

    Demo portal build with widget and components of the UI package

Other usage examples will come soon!

API Dependencies

All the JavaScript libraries used by this API are included in the full minified file.

However if you use this API with other APIs, it is possible that one or more libraries included in the full minified file generate conflicts with other libraries. In that case download the light minified file and try to solve the conflicts by adding the required libraries separately.

Currently the API requires the the following libraries (included in the full minified file): The following CSS is required with the API UI module components GINodeTree and ConceptTree: The following CSS is required with the API UI module component TermFrequencyWidget: The following OpenLayers 3 CSS are required: If you want to apply the JQuery UI theme to the jTable of the TermFrequencyWidget, add the following script:

                            <script type="text/javascript">
                                $.extend(true, $.hik.jtable.prototype.options, {
                                    jqueryuiTheme: true