In the game model class, the application records Game objects in a metadata block each time it saves a game in
DynamoDB. Separately, the application records game IDs in annotations for use with filter expressions.
Example src/main/java/scorekeep/GameModel.java
import com.amazonaws.xray.AWSXRay;
import com.amazonaws.xray.entities.Segment;
import com.amazonaws.xray.entities.Subsegment;
...
public void saveGame(Game game) throws SessionNotFoundException {
// wrap in subsegment
Subsegment subsegment = AWSXRay.beginSubsegment("## GameModel.saveGame");
try {
// check session
String sessionId = game.getSession();
if (sessionModel.loadSession(sessionId) == null ) {
throw new SessionNotFoundException(sessionId);
}
Segment segment = AWSXRay.getCurrentSegment();
subsegment.putMetadata("resources", "game", game);
segment.putAnnotation("gameid", game.getId());
mapper.save(game);
} catch (Exception e) {
subsegment.addException(e);
throw e;
} finally {
AWSXRay.endSubsegment();
}
}In the move controller, the application records user IDs with setUser. User IDs
are recorded in a separate field on segments and are indexed for use with search.
Example src/main/java/scorekeep/MoveController.java
import com.amazonaws.xray.AWSXRay;
...
@RequestMapping(value="/{userId}", method=RequestMethod.POST)
public Move newMove(@PathVariable String sessionId, @PathVariable String gameId, @PathVariable String userId, @RequestBody String move) throws SessionNotFoundException, GameNotFoundException, StateNotFoundException, RulesException {
AWSXRay.getCurrentSegment().setUser(userId);
return moveFactory.newMove(sessionId, gameId, userId, move);
}