Topics

Packages > @fluidframework/datastore-definitions > IChannel

IChannel Interface

Signature

export interface IChannel extends IFluidLoadable

Extends: IFluidLoadable

Properties

Property	Modifiers	Type	Description
attributes	`readonly`	IChannelAttributes
id	`readonly`	string	A readonly identifier for the channel

Methods

Method	Return Type	Description
connect(services)	void	Enables the channel to send and receive ops.
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.
getGCData(fullGC)	IGarbageCollectionData	Returns the GC data for this channel. It contains a list of GC nodes that contains references to other GC nodes.
isAttached()	boolean	Checks if the channel is attached to storage.
summarize(fullTree, trackState, telemetryContext, incrementalSummaryContext)	Promise<ISummaryTreeWithStats>	Generates summary of the channel asynchronously. This should not be called where the channel can be modified while summarization is in progress.

Property Details

attributes

Signature

readonly attributes: IChannelAttributes;

id

A readonly identifier for the channel

Signature

readonly id: string;

Method Details

connect

Enables the channel to send and receive ops.

Signature

connect(services: IChannelServices): void;

Parameters

Parameter	Type	Description
services	IChannelServices	The services to connect to.

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.

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 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 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.

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

isAttached

Checks if the channel is attached to storage.

Signature

isAttached(): boolean;

Returns

True iff the channel is attached.

Return type: boolean

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, 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 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 >