com.amazon.ask.attributes

Class AttributesManager

java.lang.Object

com.amazon.ask.attributes.AttributesManager

public class AttributesManager
extends Object

Manager for all skill attributes. This manager is passed to request handlers, request and response interceptors, and exception handlers to expose attribute retrieval and saving operations.

Skill attributes can be stored on three levels:

• Request: Request attributes only last within a single request processing lifecycle. Request attributes are initially empty when a request comes in, and are discarded once a response has been produced.
• Session: Session attributes persist throughout the lifespan of the current skill session. Session attributes are available for use with any in-session request. Any attributes set during the request processing lifecycle are sent back to the Alexa service and provided via the next request in the same session.
• Persistent: Persistent attributes persist beyond the lifecycle of the current session. How these attributes are stored, including key scope (user ID or device ID), TTL, and storage layer depends on skill configuration and/or the persistence adapter being used. If no persistence adapter is configured persistent attributes cannot be used.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AttributesManager.Builder Attributes Manager Builder class.

Field Summary

Fields

Modifier and Type	Field and Description
protected PersistenceAdapter	persistenceAdapter Adapter layer used to persist Skill data.
protected boolean	persistenceAttributesSet Check to see if persistence attributes have been set.
protected Map<String,Object>	persistentAttributes Data stored in persistence layer (Eg: AWS DynamoDB).
protected Map<String,Object>	requestAttributes Request attributes.
protected RequestEnvelope	requestEnvelope Request envelope object which encapsulates Request, Session, context and the current version.
protected Map<String,Object>	sessionAttributes Data stored in session as key-value pairs.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AttributesManager(PersistenceAdapter persistenceAdapter, RequestEnvelope requestEnvelope) Constructor for AttributesManager.

Method Summary

Modifier and Type	Method and Description
static AttributesManager.Builder	builder() Static builder method which returns an instance of Builder.
void	deletePersistentAttributes() Deletes the persistent attributes from the persistence layer.
Map<String,Object>	getPersistentAttributes() Retrieves current persistence attributes.
Map<String,Object>	getRequestAttributes() Retrieves current request attributes.
Map<String,Object>	getSessionAttributes() Retrieves current session attributes.
void	savePersistentAttributes() Saves the current persistent attribute state back to the persistence layer.
void	setPersistentAttributes(Map<String,Object> persistentAttributes) Sets persistent attributes.
void	setRequestAttributes(Map<String,Object> requestAttributes) Sets request attributes.
void	setSessionAttributes(Map<String,Object> sessionAttributes) Sets session attributes, replacing any existing attributes already present in the session.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

requestEnvelope

protected final RequestEnvelope requestEnvelope

Request envelope object which encapsulates Request, Session, context and the current version.

persistenceAdapter

protected final PersistenceAdapter persistenceAdapter

Adapter layer used to persist Skill data.

sessionAttributes

protected Map<String,Object> sessionAttributes

Data stored in session as key-value pairs.

persistentAttributes

protected Map<String,Object> persistentAttributes

Data stored in persistence layer (Eg: AWS DynamoDB).

requestAttributes

protected Map<String,Object> requestAttributes

Request attributes.

persistenceAttributesSet

protected boolean persistenceAttributesSet

Check to see if persistence attributes have been set.

Constructor Detail

AttributesManager

protected AttributesManager(PersistenceAdapter persistenceAdapter,
                            RequestEnvelope requestEnvelope)

Constructor for AttributesManager.

Parameters:

persistenceAdapter - Adapter layer used to persist Skill data.

requestEnvelope - Request envelope object which encapsulates Request, Session, context and the current version.

Method Detail

builder

public static AttributesManager.Builder builder()

Static builder method which returns an instance of Builder.

Returns:

AttributesManager.Builder.

getSessionAttributes

public Map<String,Object> getSessionAttributes()

Retrieves current session attributes. If existing session attributes are present, they will be contained in the returned map. If not, an empty map will be returned. Modifications to this map will be saved back to the session. An exception is thrown if this method is called while processing an out of session request.

Returns:

map containing existing session attributes, or an empty map if none exist

Throws:

IllegalStateException - if attempting to retrieve session attributes from an out of session request

setSessionAttributes

public void setSessionAttributes(Map<String,Object> sessionAttributes)

Sets session attributes, replacing any existing attributes already present in the session. An exception is thrown if this method is called while processing an out of session request. Use this method when bulk replacing attributes is desired.

Parameters:

sessionAttributes - session attributes to set

Throws:

IllegalStateException - if attempting to retrieve session attributes from an out of session request

getPersistentAttributes

public Map<String,Object> getPersistentAttributes()

Retrieves current persistence attributes. If existing persistence attributes are present, they will be contained in the returned map. If not, an empty map will be returned. Modifications to this map will not be persisted back unless savePersistentAttributes() is called. An exception is thrown if this method is called when a PersistenceAdapter is not configured on the SDK.

Returns:

map containing existing persistence attributes, or an empty map if none exist

Throws:

IllegalStateException - if no PersistenceAdapter is configured

setPersistentAttributes

public void setPersistentAttributes(Map<String,Object> persistentAttributes)

Sets persistent attributes. The attributes set using this method will replace any existing persistent attributes, but the changes will not be persisted back until savePersistentAttributes() is called. Use this method when bulk replacing attributes is desired. An exception is thrown if this method is called when a PersistenceAdapter is not configured on the SDK.

Parameters:

persistentAttributes - persistent attributes to set

Throws:

IllegalStateException - if no PersistenceAdapter is configured

getRequestAttributes

public Map<String,Object> getRequestAttributes()

Retrieves current request attributes. If existing request attributes are present, they will be contained in the returned map. If not, an empty map will be returned.

Returns:

map containing existing request attributes, or an empty map if none exist

setRequestAttributes

public void setRequestAttributes(Map<String,Object> requestAttributes)

Sets request attributes. This attributes set using this method will replace any existing request attributes. Use this method when bulk replacing attributes is desired.

Parameters:

requestAttributes - request attributes to set

savePersistentAttributes

public void savePersistentAttributes()

Saves the current persistent attribute state back to the persistence layer. This method should only be called when all attribute modifications are complete, and generally should only be called once since to avoid unnecessary writes to the persistence tier. An exception is thrown if this method is called when a PersistenceAdapter is not configured on the SDK.

Throws:

IllegalStateException - if no PersistenceAdapter is configured

deletePersistentAttributes

public void deletePersistentAttributes()

Deletes the persistent attributes from the persistence layer. An exception is thrown if this method is called when a PersistenceAdapter is not configured on the SDK.

Throws:

IllegalStateException - if no PersistenceAdapter is configured