This library is intended to be a toolkit for using xAPI in Java. Right now it has Jackson model objects for serialization and deserialization of xAPI statements, as well as a configured Jackson ObjectMapper to perform the operations.
This library comes with a model of xAPI Statements and components which should allow easy conversion between Java Objects and JSON. Currently it is tailored to support xAPI Version 1.0.0-1.0.3. Newer versions will be supported in the future.
Deserialization can be performed on xAPI Strings or files or inputstreams using the provided ObjectMapper.
Take the following xAPI Statement:
{
"id": "6fbd600f-b17c-4c74-801a-2ec2e53231c8",
"actor": { "mbox": "mailto:[email protected]" },
"verb": {"id": "https://xapi.yetanalytics.com/profile/concepts/verbs/did" },
"object": {"id": "https://xapi.yetanalytics.com/profile/concepts/activities/act1" },
"timestamp": "2023-10-27T09:03:21.723Z",
"stored": "2023-10-27T09:03:21.723Z"
}
You can turn it into a Statement Object like so:
import com.yetanalytics.xapi.model.Statement;
import com.yetanalytics.xapi.util.Mapper;
...
Statement stmt = Mapper.getMapper().readValue(xApiString, Statement.class);
System.out.println(stmt.getVerb().getId());
//-> "https://xapi.yetanalytics.com/profile/concepts/verbs/did"
The process for creating xAPI JSON is very similar, just take one of the objects write it out.
String xapi = Mapper.getMapper().writeValueAsString(stmt);
Which produces a JSON statement identical to the one at the top.
If you need to create your own ObjectMapper or prefer to use an existing one in your project, please refer to the additional configuration in Mapper.java. The most important is adding the Java Time module to the Mapper because it does not ship with java.time support.
A very basic LRS Client has been added to deal with statements only (not attachments). Other resources and attachments will be added in the future.
You must create an LRS object with host and prefix, and credentials in order to initialize a client. Here is a code sample of API usage:
//presume some statements using the model
List<Statement> stmts = new ArrayList<>(List.of(stmt1, stmt2));
LRS lrs = new LRS("https://lrs.yetanalytics.com/xapi/", "username", "password");
StatementClient client = new StatementClient(lrs);
List<UUID> resultIds = client.postStatements(stmts);
Note the format of the host. It includes the prefix path, but excludes resources like /statements. The trailing / is optional.
Current API methods include:
List<UUID> postStatements(List<Statement> stmts)
List<UUID> postStatement(Statement stmt)
List<Statement> getStatements(StatementFilters filters)
List<Statement> getStatements()
The client will batch at the size (optionally) provided to the LRS object. It will also handle retrieving the results from more links when the LRS paginates responses.
A StatementFilters object can optionally be given to the getStatements method to allow for all xAPI statement resource filter types (except attachment).
More methods will be added in future to support other resources and also attachments.
Coming Soon...
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Distributed under the Apache License version 2.0.