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Version: v1

SharedObject Class

SharedObject with simplified, synchronous summarization and GC. DDS implementations with async and incremental summarization should extend SharedObjectCore directly instead.

Signature

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

Extends: SharedObjectCore

Type Parameters

Parameter Constraint Default Description
TEvent ISharedObjectEvents ISharedObjectEvents

Constructors

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

Properties

Property Type Description
serializer IFluidSerializer

Methods

Method Return Type Description
getAttachSummary(fullTree, trackState, telemetryContext) 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. Note: Since 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 ISummaryAttachment (handles to blobs uploaded async via the blob manager).
getGCData(fullGC) IGarbageCollectionData Returns the GC data for this shared object. It contains a list of GC nodes that contains references to other GC nodes.
processGCDataCore(serializer) 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) 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) ISummaryTreeWithStats Gets a form of the object that can be serialized.

Constructor Details

(constructor)

Constructs a new instance of the SharedObject class

Signature

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

Parameters

Parameter Type Description
id string The id of the shared object
runtime IFluidDataStoreRuntime The IFluidDataStoreRuntime which contains the shared object
attributes IChannelAttributes Attributes of the shared object
telemetryContextPrefix string

Property Details

serializer

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. Note: Since 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 ISummaryAttachment (handles to blobs uploaded async via the blob manager).

Signature

getAttachSummary(fullTree?: boolean, trackState?: boolean, telemetryContext?: ITelemetryContext): 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.
trackState optional boolean optimization for tracking state of objects across summaries. If the state of an object did not change since last successful summary, an 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
telemetryContext optional ITelemetryContext

Returns

A summary capturing the current state of the channel.

Return type: ISummaryTreeWithStats

getGCData

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

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.

Signature

protected processGCDataCore(serializer: SummarySerializer): void;

Parameters

Parameter Type Description
serializer SummarySerializer

summarize

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

Signature

summarize(fullTree?: boolean, trackState?: boolean, telemetryContext?: ITelemetryContext): 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 is only set to true when generating a summary from the entire container.
trackState optional boolean This tells whether we should track state from this summary.
telemetryContext optional ITelemetryContext

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.

Signature

protected abstract summarizeCore(serializer: IFluidSerializer, telemetryContext?: ITelemetryContext): ISummaryTreeWithStats;

Parameters

Parameter Modifiers Type Description
serializer IFluidSerializer
telemetryContext optional ITelemetryContext

Returns

A tree representing the snapshot of the shared object.

Return type: ISummaryTreeWithStats