Package org.apache.druid.discovery

Class DataNodeService

java.lang.Object

org.apache.druid.discovery.DruidService

org.apache.druid.discovery.DataNodeService

public class DataNodeService
extends DruidService

Metadata announced by any node that serves segments. Note for JSON serialization and deserialization. This class has a bug that it has the "type" property which is the duplicate name with the subtype key of DruidService. It seems to happen to work if the "type" subtype key appears first in the serialized JSON since Jackson uses the first "type" property as the subtype key. To always enforce this property order, this class does not use the JsonProperty annotation for serialization, but uses DruidServiceSerializer. Since this is a hacky-way to not break compatibility, a new "serverType" field is added to replace the deprecated "type" field. Once we completely remove the "type" field from this class, we can remove DruidServiceSerializer as well. The set of properties to serialize is hard-coded in DruidServiceSerializer. If you want to add a new field in this class before we remove the "type" field, you must add a proper handling of that new field in DruidServiceSerializer as well. For deserialization, DruidServices are deserialized as a part of DiscoveryDruidNode. To handle the bug of the duplicate "type" key, DiscoveryDruidNode first deserializes the JSON to StringObjectPairList, handles the duplicate "type" keys in the StringObjectPairList, and then finally converts it to a DruidService. See DiscoveryDruidNode.toMap(List).

See Also:

• DruidServiceSerializer
• DiscoveryDruidNode.toMap(List)

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DISCOVERY_SERVICE_KEY
static final String	SERVER_TYPE_PROP_KEY

Constructor Summary

Constructors

Constructor	Description
DataNodeService(String tier, long maxSize, ServerType serverType, int priority)
DataNodeService(String tier, long maxSize, ServerType serverType, int priority, boolean isDiscoverable)

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object o)
static DataNodeService	fromJson(String tier, long maxSize, ServerType type, ServerType serverType, int priority)	This JSON creator requires for the "type" subtype key of DruidService to appear before the "type" property of this class in the serialized JSON.
long	getMaxSize()
String	getName()
int	getPriority()
ServerType	getServerType()
String	getTier()
int	hashCode()
boolean	isDiscoverable()
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

DISCOVERY_SERVICE_KEY

public static final String DISCOVERY_SERVICE_KEY

See Also:

• Constant Field Values

SERVER_TYPE_PROP_KEY

public static final String SERVER_TYPE_PROP_KEY

See Also:

• Constant Field Values

Constructor Details

DataNodeService

public DataNodeService(String tier,
 long maxSize,
 ServerType serverType,
 int priority)

DataNodeService

public DataNodeService(String tier,
 long maxSize,
 ServerType serverType,
 int priority,
 boolean isDiscoverable)

Method Details

fromJson

public static DataNodeService fromJson(String tier,
 long maxSize,
 @Deprecated @Nullable
 ServerType type,
 @Nullable
 ServerType serverType,
 int priority)

This JSON creator requires for the "type" subtype key of DruidService to appear before the "type" property of this class in the serialized JSON. Deserialization can fail otherwise. See the Javadoc of this class for more details.

getName

public String getName()

Specified by:

getName in class DruidService

getTier

public String getTier()

getMaxSize

public long getMaxSize()

getServerType

public ServerType getServerType()

getPriority

public int getPriority()

isDiscoverable

public boolean isDiscoverable()

Overrides:

isDiscoverable in class DruidService

Returns:

Whether the service should be discoverable. The default implementation returns true. Some implementations may choose to override this so that the service is not discoverable if it has not been configured. This will not throw a fatal exception, but instead will just skip binding and log a message. This could be useful for optional configuration for the service.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object