ISTI CNR sandro.labruzzo@isti.cnr.it Object Store Service is a DNet service that provides functions for perstistent storage of files, and provides a REST API for fetching them back. It is composed by three different sub-modules: dnet-objectstore -rmi: it contains the interface of the Object Store Service and includes some utility classes defining metadata information for each file (i.e., ObjectStoreFile). These metadata allow the Object Store Service to store and fetch the associated files in a consistent way. dnet-modular-objectstore-service: it contains the high level implementation of the service. It manages blackboard messages, the creation of profiles in dnet, and defines the REST API. dnet-gridfs-objectstore: low level implementation for storing and retreiving files using mongo GRIDFS. To enable the object store to store a file, it is necessary give some information about it such as: ObjectID (Required to identify the file) Mime type Access protocol (required). At the moment the only protocols available are: http, ftp, file system. URI (required) username, password for connection (optional, if needed). Feeding Object Store Service can be done in two different ways: Feed of a single file: performed by invoking the following web service method feedObject( String obsId, String objectMetadata)where objectMetadata is a JSON serialization of an ObjectStoreFile instance defined in the objectStore-RMI. Feed of multiple files in bulk: performed via blackboard message on the profile of the Object Store Service. The blackboard message has to specify an EPR of ObjectStoreFile result set and the targeted the ObjectstoreID. Please find two example of feeding techniques below. The code below shows how to upload a single file into an objectStore private void feedTest(ServiceLocator <ObjectStoreService> ObjectStoreServicelocator, String objectStoreID) throws ObjectStoreServiceException { //Get a reference of the Service ObjectStoreService obsService = ObjectStoreServicelocator.getService(); //Create the FILE ObjectStoreFile metadataFile = new ObjectStoreFile(); metadataFile.setObjectID("MyID"); metadataFile.setMimeType("pdf"); metadataFile.setURI("ftp://myURL/FTP"); metadataFile.setAccessProtocol(Protocols.FTP); //Could be unnecessary metadataFile.setUsernameAuth("usr"); metadataFile.setPasswordAuth("pwd"); //Feed obsService.feedObject(objectStoreID, metadataFile.toJSON()); } The feeding of multiple objects can be performed by the mechanism of bloackboard messaging within the profile service of the objectStore. The code Below shows an example of feeding inside an example BlackBoardJobNode belonging to a workflow. protected void prepareJob(final BlackboardJob job, final NodeToken token) { final String epr = token.getEnv().getAttribute("epr"); final String objectStoreID = token.getEnv().getAttribute("objectStoreID"); super.prepareJob(job, token); job.setAction("FEED"); try { job.getParameters().put("epr",new String(Base64.encodeBase64(epr.getBytes("US-ASCII")), "US-ASCII")); } catch (UnsupportedEncodingException e) { throw new RuntimeException("ERROR " + e.getMessage()); } job.getParameters().put("obsID",objectStoreID); }