How to determine the weather the endpoint (KAA SDK) is connected to the KAA server or not from the application

Question

Is there any mechanism or method or steps for detecting the endpoint connection (KAA SDK) to the KAA server from the application.

If not, how can we remotely identify failure devices? or How can we identify devices that cannot communicate with the KAA server after deploying devices in the field?

How can this requirement be achieved to unlock IOT power?

Answer 1

If your endpoint encounters some problems with the Kaa server, a "switch to another resource" will occur.

, Kaa. onFialover().

Java SDK.

  import org.kaaproject.kaa.client.DesktopKaaPlatformContext;
  import org.kaaproject.kaa.client.Kaa;
  import org.kaaproject.kaa.client.KaaClient;
  import org.kaaproject.kaa.client.SimpleKaaClientStateListener;
  import org.kaaproject.kaa.client.channel.failover.FailoverDecision;
  import org.kaaproject.kaa.client.channel.failover.FailoverStatus;
  import org.kaaproject.kaa.client.channel.failover.strategies.DefaultFailoverStrategy;
  import org.kaaproject.kaa.client.exceptions.KaaRuntimeException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;

  import java.io.IOException;
  import java.util.concurrent.TimeUnit;

  /**
  * A demo application that shows how to use the Kaa credentials API.
  */
  public class CredentialsDemo {
  private static final Logger LOG = LoggerFactory.getLogger(CredentialsDemo.class);
  private static KaaClient kaaClient;

  public static void main(String[] args) throws InterruptedException, IOException {

  LOG.info("Demo application started");

  try {

  // Create a Kaa client and add a startup listener
  kaaClient = Kaa.newClient(new DesktopKaaPlatformContext(), new SimpleKaaClientStateListener() {
  @Override
  public void onStarted() {
  super.onStarted();
  LOG.info("Kaa client started");
  }
  }, true);

  kaaClient.setFailoverStrategy(new CustomFailoverStrategy());
  kaaClient.start();

  // ... Do some work ...

  LOG.info("Stopping application.");
  kaaClient.stop();

  } catch (KaaRuntimeException e) {
  LOG.info("Cannot connect to server - no credentials found.");
  LOG.info("Stopping application.");
  }

  }

  // Give a possibility to manage device behavior when it loses connection
  // or has other problems dealing with Kaa server.
  private static class CustomFailoverStrategy extends DefaultFailoverStrategy {

  @Override
  public FailoverDecision onFailover(FailoverStatus failoverStatus) {
  LOG.info("Failover happen. Failover type: " + failoverStatus);

  // See enum DefaultFailoverStrategy from package org.kaaproject.kaa.client.channel.failover
  // to list all possible values
  switch (failoverStatus) {
  case CURRENT_BOOTSTRAP_SERVER_NA:
  LOG.info("Current Bootstrap server is not available. Trying connect to another one.");

  // ... Do some recovery, send notification messages, etc. ...

  // Trying to connect to another bootstrap node one-by-one every 5 seconds
  return new FailoverDecision(FailoverDecision.FailoverAction.USE_NEXT_BOOTSTRAP, 5L, TimeUnit.SECONDS);
  default:
  return super.onFailover(failoverStatus);
  }
  }
  }
  }

(2016/10/28)

, checkCredentialsStatus(), . IN_USE , .

, Kaa , . .

  package org.kaaproject.kaa.examples.credentials.kaa;

  import org.kaaproject.kaa.common.dto.ApplicationDto;
  import org.kaaproject.kaa.common.dto.admin.AuthResultDto;
  import org.kaaproject.kaa.common.dto.credentials.CredentialsStatus;
  import org.kaaproject.kaa.examples.credentials.utils.IOUtils;
  import org.kaaproject.kaa.server.common.admin.AdminClient;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;

  import java.util.List;

  public class KaaAdminManager {

  private static final Logger LOG = LoggerFactory.getLogger(KaaAdminManager.class);

  private static final int DEFAULT_KAA_PORT = 8080;
  private static final String APPLICATION_NAME = "Credentials demo";

  public String tenantAdminUsername = "admin";
  public String tenantAdminPassword = "admin123";

  private AdminClient adminClient;

  public KaaAdminManager(String sandboxIp) {
  this.adminClient = new AdminClient(sandboxIp, DEFAULT_KAA_PORT);
  }

  // ...

  /**
  * Check credentials status for getting information
  * @return credential status
  */
  public void checkCredentialsStatus() {
  LOG.info("Enter endpoint ID:");

  // Reads endpoint ID (aka "endpoint key hash") from user input
  String endpointId = IOUtils.getUserInput().trim();

  LOG.info("Getting credentials status...");
  try {
  ApplicationDto app = getApplicationByName(APPLICATION_NAME);
  String appToken = app.getApplicationToken();

  // CredentialsStatus can be: AVAILABLE, IN_USE, REVOKED
  // if endpoint is not found on Kaa server, exception will be thrown
  CredentialsStatus status = adminClient.getCredentialsStatus(appToken, endpointId);
  LOG.info("Credentials for endpoint ID = {} are now in status: {}", endpointId, status.toString());
  } catch (Exception e) {
  LOG.error("Get credentials status for endpoint ID = {} failed. Error: {}", endpointId, e.getMessage());
  }
  }

  /**
  * Get application object by specified application name
  */
  private ApplicationDto getApplicationByName(String applicationName) {
  checkAuthorizationAndLogin();

  try {
  List<ApplicationDto> applications = adminClient.getApplications();
  for (ApplicationDto application : applications) {
  if (application.getName().trim().equals(applicationName)) {
  return application;
  }
  }
  } catch (Exception e) {
  LOG.error("Exception has occurred: " + e.getMessage());
  }
  return null;
  }

  /**
  * Checks authorization and log in
  */
  private void checkAuthorizationAndLogin() {
  if (!checkAuth()) {
  adminClient.login(tenantAdminUsername, tenantAdminPassword);
  }
  }

  /**
  * Do authorization check
  * @return true if user is authorized, false otherwise
  */
  private boolean checkAuth() {
  AuthResultDto.Result authResult = null;
  try {
  authResult = adminClient.checkAuth().getAuthResult();
  } catch (Exception e) {
  LOG.error("Exception has occurred: " + e.getMessage());
  }
  return authResult == AuthResultDto.Result.OK;
  }

  }

AdminClient KaaAdminManager Demo Application Kaa GitHub.

• Kaa Notifications Kaa Data Collection . ( ), . appender ( ) ( ). , .
• Kaa Data Collection. , . , Kaa ( ..). . , "-", ( ), ( ) .

* Kaa Data Collection, Log appender ( Kaa Admin UI): " " ( , " " ), " ". , .

Answer 2

Kaa , SDK, - , , . , , .