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List devices

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Retrieves the identifiers of devices for a specific registry.

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For detailed documentation that includes this code sample, see the following:

Code sample

Go

For more information, see the Cloud IoT Core Go API reference documentation. 


// listDevices gets the identifiers of devices for a specific registry.
func listDevices(w io.Writer, projectID string, region string, registryID string) ([]*cloudiot.Device, error) {
	// Authorize the client using Application Default Credentials.
	// See https://g.co/dv/identity/protocols/application-default-credentials
	ctx := context.Background()
	httpClient, err := google.DefaultClient(ctx, cloudiot.CloudPlatformScope)
	if err != nil {
		return nil, err
	}
	client, err := cloudiot.New(httpClient)
	if err != nil {
		return nil, err
	}

	parent := fmt.Sprintf("projects/%s/locations/%s/registries/%s", projectID, region, registryID)
	response, err := client.Projects.Locations.Registries.Devices.List(parent).Do()
	if err != nil {
		return nil, err
	}

	fmt.Fprintln(w, "Devices:")
	for _, device := range response.Devices {
		fmt.Fprintf(w, "\t%s\n", device.Id)
	}

	return response.Devices, nil
}

Java

For more information, see the Cloud IoT Core Java API reference documentation. 

/** Print all of the devices in this registry to standard out. */
protected static void listDevices(String projectId, String cloudRegion, String registryName)
    throws GeneralSecurityException, IOException {
  GoogleCredentials credential =
      GoogleCredentials.getApplicationDefault().createScoped(CloudIotScopes.all());
  JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();
  HttpRequestInitializer init = new HttpCredentialsAdapter(credential);
  final CloudIot service =
      new CloudIot.Builder(GoogleNetHttpTransport.newTrustedTransport(), jsonFactory, init)
          .setApplicationName(APP_NAME)
          .build();

  final String registryPath =
      String.format(
          "projects/%s/locations/%s/registries/%s", projectId, cloudRegion, registryName);

  List<Device> devices =
      service
          .projects()
          .locations()
          .registries()
          .devices()
          .list(registryPath)
          .execute()
          .getDevices();

  if (devices != null) {
    System.out.println("Found " + devices.size() + " devices");
    for (Device d : devices) {
      System.out.println("Id: " + d.getId());
      if (d.getConfig() != null) {
        // Note that this will show the device config in Base64 encoded format.
        System.out.println("Config: " + d.getConfig().toPrettyString());
      }
      System.out.println();
    }
  } else {
    System.out.println("Registry has no devices.");
  }
}

Node.js

For more information, see the Cloud IoT Core Node.js API reference documentation. 

// const cloudRegion = 'us-central1';
// const projectId = 'adjective-noun-123';
// const registryId = 'my-registry';
const iot = require('@google-cloud/iot');
const iotClient = new iot.v1.DeviceManagerClient({
  // optional auth parameters.
});

async function listDevices() {
  // Construct request
  const parentName = iotClient.registryPath(
    projectId,
    cloudRegion,
    registryId
  );

  // See full list of device fields: https://cloud.google.com/iot/docs/reference/cloudiot/rest/v1/projects.locations.registries.devices
  // Warning! Use snake_case field names.
  const fieldMask = {
    paths: [
      'id',
      'name',
      'num_id',
      'credentials',
      'last_heartbeat_time',
      'last_event_time',
      'last_state_time',
      'last_config_ack_time',
      'last_config_send_time',
      'blocked',
      'last_error_time',
      'last_error_status',
      'config',
      'state',
      'log_level',
      'metadata',
      'gateway_config',
    ],
  };

  const [response] = await iotClient.listDevices({
    parent: parentName,
    fieldMask,
  });
  const devices = response;

  if (devices.length > 0) {
    console.log('Current devices in registry:');
  } else {
    console.log('No devices in registry.');
  }

  for (let i = 0; i < devices.length; i++) {
    const device = devices[i];
    console.log(`Device ${i}: `, device);
  }
}

listDevices();

PHP

For more information, see the Cloud IoT Core PHP API reference documentation. 

use Google\Cloud\Iot\V1\DeviceManagerClient;

/**
 * List all devices in the registry.
 *
 * @param string $registryId IOT Device Registry ID
 * @param string $projectId Google Cloud project ID
 * @param string $location (Optional) Google Cloud region
 */
function list_devices(
    $registryId,
    $projectId,
    $location = 'us-central1'
) {
    print('Listing devices' . PHP_EOL);

    // Instantiate a client.
    $deviceManager = new DeviceManagerClient();

    // Format the full registry path
    $registryName = $deviceManager->registryName($projectId, $location, $registryId);

    // Call the API
    $devices = $deviceManager->listDevices($registryName);

    // Print the result
    foreach ($devices->iterateAllElements() as $device) {
        printf('Device: %s : %s' . PHP_EOL,
            $device->getNumId(),
            $device->getId());
    }
}

Python

For more information, see the Cloud IoT Core Python API reference documentation. 

# project_id = 'YOUR_PROJECT_ID'
# cloud_region = 'us-central1'
# registry_id = 'your-registry-id'
print("Listing devices")

client = iot_v1.DeviceManagerClient()
registry_path = client.registry_path(project_id, cloud_region, registry_id)

# See full list of device fields: https://cloud.google.com/iot/docs/reference/cloudiot/rest/v1/projects.locations.registries.devices
# Warning! Use snake_case field names.
field_mask = gp_field_mask.FieldMask(
    paths=[
        "id",
        "name",
        "num_id",
        "credentials",
        "last_heartbeat_time",
        "last_event_time",
        "last_state_time",
        "last_config_ack_time",
        "last_config_send_time",
        "blocked",
        "last_error_time",
        "last_error_status",
        "config",
        "state",
        "log_level",
        "metadata",
        "gateway_config",
    ]
)

devices = list(
    client.list_devices(request={"parent": registry_path, "field_mask": field_mask})
)
for device in devices:
    print(device)

return devices

Ruby

For more information, see the Cloud IoT Core Ruby API reference documentation. 

# project_id  = "Your Google Cloud project ID"
# location_id = "The Cloud region the registry is located in"
# registry_id = "The registry to list devices from"

require "google/apis/cloudiot_v1"

# Initialize the client and authenticate with the specified scope
Cloudiot   = Google::Apis::CloudiotV1
iot_client = Cloudiot::CloudIotService.new
iot_client.authorization = Google::Auth.get_application_default(
  "https://www.googleapis.com/auth/cloud-platform"
)

# The resource name of the location associated with the project
resource = "projects/#{project_id}/locations/#{location_id}/registries/#{registry_id}"

# List the devices in the provided region
response = iot_client.list_project_location_registry_devices(
  resource
)

puts "Devices:"
if response.devices && response.devices.any?
  response.devices.each { |device| puts "\t#{device.id}" }
else
  puts "\tNo device registries found in this region for your project."
end

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