Scripting the repository using Javascript

Introduction

Rhino, a Java-based Javascript implementation, makes it easy to use the Java API of the repository server to automate all kinds of operations. In other words: easy scripting of the repository server. It brings all the benefits of Daisy's high-level repository API without requiring Java knowledge or the setup of a development environment.

How does it work?

1. Write a Javascript, save it in a ".js" file.
2. Open a command prompt or shell, set the DAISY_HOME environment variable to point to your Daisy installation
3. Go to the directory <DAISY_HOME>/bin
4. Execute "daisy-js <name-of-scriptfile>"

Connecting to the repository server from Javascript

The basic code you need to connect to the repository server from Javascript is the following:

importPackage(Packages.org.outerj.daisy.repository);
importClass(Packages.org.outerj.daisy.repository.clientimpl.RemoteRepositoryManager);

var repositoryManager = new RemoteRepositoryManager("http://localhost:9263",
                                                    new Credentials("testuser", "testuser"));
var repository = repositoryManager.getRepository(new Credentials("testuser", "testuser"));

Some explanation:

The importPackage and importClass statements are used to make the Daisy Java API available in the Javascript environment.

Then a RepositoryManager is constructed, this is an object from which Repository objects can be retrieved. A Repository object represents a connection to the Daisy Repository Server for a certain user. Typically, you only construct one RepositoryManager, and then retrieve different Repository objects from it if you want to perform actions under different users.

The first argument of the RepositoryManager constructor is the address of the HTTP interface of the repository server (9263 is the default port). The second argument is a username and password for a user that is used inside the implementation to fill up caches. Currently, this user has to be a user which has the Administrator role. (Inside the implementation, some often needed info like the repository schema and the collections is cached)

Then from the RepositoryManager a Repository for a specific user is retrieved. Here we use the same credentials as for the cache user of the RepositoryManager, but this doesn't have to be the case.

Repository Java API documentation

Reference documentation of the Daisy API is included in the binary distribution in the apidocs directory (open the file index.html in a web browser). See also Java API.

Examples

Creating a document (uploading an image)

This example uploads an image called "myimage.gif" from the current directory into the repository.

importPackage(Packages.org.outerj.daisy.repository);
importClass(Packages.org.outerj.daisy.repository.clientimpl.RemoteRepositoryManager);

var repositoryManager = new RemoteRepositoryManager("http://localhost:9263",
                                                    new Credentials("testuser", "testuser"));
var repository = repositoryManager.getRepository(new Credentials("testuser", "testuser"));

var document = repository.createDocument("My test image", "Image");
var imageFile = new java.io.File("myimage.gif");
document.setPart("ImageData", "image/gif", new FilePartDataSource(imageFile));
document.save();

print("Document created, ID = " + document.getId());

See the API documentation for the purpose of the arguments of the methods. For example, the text "Image" supplied as the second argument of the createDocument method is the name of the document type to use for the document. Likewise, the first argument of setPart, "ImageData", is the name of the part.

It would be an interesting exercise to extend this example to upload a whole directory of images :-)

Performing a query

importPackage(Packages.org.outerj.daisy.repository);
importClass(Packages.org.outerj.daisy.repository.clientimpl.RemoteRepositoryManager);
importPackage(Packages.java.util);

var repositoryManager = new RemoteRepositoryManager("http://localhost:9263",
                                                    new Credentials("testuser", "testuser"));
var repository = repositoryManager.getRepository(new Credentials("testuser", "testuser"));
var queryManager = repository.getQueryManager();

var searchresults = queryManager.performQuery("select id, name where true", Locale.getDefault());
var rows = searchresults.getSearchResult().getRows().getRowArray();
for (var i = 0; i < rows.length; i++) {
  print(rows[i].getValueArray(0) + " : " + rows[i].getValueArray(1));
}

print("Total number: " + rows.length);

Your example here

If you've got a cool example to contribute, just write to the Daisy mailing list.