SharedObject Class

Helper for implementing ISharedObject with simplified, synchronous summarization and garbage collection.

This API is provided for existing users, but is not recommended for new users.

To use, import via @fluidframework/shared-object-base/legacy.

For more information about our API support guarantees, see here.

Signature

export declare abstract class SharedObject<TEvent extends ISharedObjectEvents = ISharedObjectEvents> extends SharedObjectCore<TEvent>

Extends: SharedObjectCore<TEvent>

Type Parameters

Parameter	Constraint	Default	Description
TEvent	ISharedObjectEvents	ISharedObjectEvents

Remarks

DDS implementations with async and incremental summarization should extend SharedObjectCore directly instead.

Constructors

Constructor	Alerts	Description
(constructor)(id, runtime, attributes, telemetryContextPrefix)	Beta	Constructs a new instance of the SharedObject class

Properties

Property	Alerts	Modifiers	Type	Description
serializer	Beta	readonly	IFluidSerializer

Methods

Method	Alerts	Return Type	Description
getAttachSummary(fullTree, trackState, telemetryContext)	Beta	ISummaryTreeWithStats	Generates summary of the channel synchronously. It is called when an attach message for a local channel is generated. In other words, when the channel is being attached to make it visible to other clients.
getGCData(fullGC)	Beta	IGarbageCollectionData	Returns the GC data for this channel. It contains a list of GC nodes that contains references to other GC nodes.
processGCDataCore(serializer)	Beta	void	Calls the serializer over all data in this object that reference other GC nodes. Derived classes must override this to provide custom list of references to other GC nodes.
summarize(fullTree, trackState, telemetryContext, incrementalSummaryContext)	Beta	Promise<ISummaryTreeWithStats>	Generates summary of the channel asynchronously. This should not be called where the channel can be modified while summarization is in progress.
summarizeCore(serializer, telemetryContext, incrementalSummaryContext, fullTree)	Beta	ISummaryTreeWithStats	Gets a form of the object that can be serialized.

Constructor Details

(constructor)

Constructs a new instance of the SharedObject class

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

constructor(id: string, runtime: IFluidDataStoreRuntime, attributes: IChannelAttributes, 
    telemetryContextPrefix: string);

Parameters

Parameter	Type	Description
id	string
runtime	IFluidDataStoreRuntime
attributes	IChannelAttributes
telemetryContextPrefix	string

Property Details

serializer

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

protected get serializer(): IFluidSerializer;

Type: IFluidSerializer

Method Details

getAttachSummary

Generates summary of the channel synchronously. It is called when an attach message for a local channel is generated. In other words, when the channel is being attached to make it visible to other clients.

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

getAttachSummary(fullTree?: boolean, trackState?: boolean, telemetryContext?: ITelemetryContext): ISummaryTreeWithStats;

Remarks

Note: Since the Attach Summary is generated for local channels when making them visible to remote clients, they don't have any previous summaries to compare against. For this reason, the attach summary cannot contain summary handles (paths to sub-trees or blobs). It can, however, contain @fluidframework/protocol-definitions#ISummaryAttachment (handles to blobs uploaded async via the blob manager).

Parameters

Parameter	Modifiers	Type	Description
fullTree	optional	boolean	A flag indicating whether the attempt should generate a full summary tree without any handles for unchanged subtrees. Default: false
trackState	optional	boolean	An optimization for tracking state of objects across summaries. If the state of an object did not change since last successful summary, an @fluidframework/protocol-definitions#ISummaryHandle can be used instead of re-summarizing it. If this is false, the expectation is that you should never send an ISummaryHandle, since you are not expected to track state. Note: The goal is to remove the trackState and automatically decided whether the handles will be used or not: https://github.com/microsoft/FluidFramework/issues/10455 Default: false
telemetryContext	optional	ITelemetryContext	See ITelemetryContext.

Returns

A summary capturing the current state of the channel.

Return type: ISummaryTreeWithStats

getGCData

Returns the GC data for this channel. It contains a list of GC nodes that contains references to other GC nodes.

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

getGCData(fullGC?: boolean): IGarbageCollectionData;

Parameters

Parameter	Modifiers	Type	Description
fullGC	optional	boolean	true to bypass optimizations and force full generation of GC data.

Returns

Return type: IGarbageCollectionData

processGCDataCore

Calls the serializer over all data in this object that reference other GC nodes. Derived classes must override this to provide custom list of references to other GC nodes.

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

protected processGCDataCore(serializer: IFluidSerializer): void;

Remarks

Serialization itself doesn't matter (the result is ignored). We're tapping into the serialization infrastructure as a way to visit all the content in this content that may reference other objects via handle.

Parameters

Parameter	Type	Description
serializer	IFluidSerializer	The "serializer" (more like handle visitor) to use. Implementations should ensure that serialize is called on all handles, as the way to visit them.

summarize

Generates summary of the channel asynchronously. This should not be called where the channel can be modified while summarization is in progress.

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

summarize(fullTree?: boolean, trackState?: boolean, telemetryContext?: ITelemetryContext, incrementalSummaryContext?: IExperimentalIncrementalSummaryContext): Promise<ISummaryTreeWithStats>;

Parameters

Parameter	Modifiers	Type	Description
fullTree	optional	boolean	flag indicating whether the attempt should generate a full summary tree without any handles for unchanged subtrees. It should only be set to true when generating a summary from the entire container. Default: false
trackState	optional	boolean	An optimization for tracking state of objects across summaries. If the state of an object did not change since last successful summary, an @fluidframework/protocol-definitions#ISummaryHandle can be used instead of re-summarizing it. If this is false, the expectation is that you should never send an ISummaryHandle, since you are not expected to track state. Default: false Note: The goal is to remove the trackState and automatically decided whether the handles will be used or not: https://github.com/microsoft/FluidFramework/issues/10455
telemetryContext	optional	ITelemetryContext	See ITelemetryContext.
incrementalSummaryContext	optional	IExperimentalIncrementalSummaryContext

Returns

A summary capturing the current state of the channel.

Return type: Promise<ISummaryTreeWithStats>

summarizeCore

Gets a form of the object that can be serialized.

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

protected abstract summarizeCore(serializer: IFluidSerializer, telemetryContext?: ITelemetryContext, incrementalSummaryContext?: IExperimentalIncrementalSummaryContext, fullTree?: boolean): ISummaryTreeWithStats;

Parameters

Parameter	Modifiers	Type	Description
serializer		IFluidSerializer
telemetryContext	optional	ITelemetryContext
incrementalSummaryContext	optional	IExperimentalIncrementalSummaryContext
fullTree	optional	boolean

Returns

A tree representing the snapshot of the shared object.

Return type: ISummaryTreeWithStats