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IDeltaHandler Interface

Handler provided by shared data structure to process requests from the runtime.

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

To use, import via @fluidframework/datastore-definitions/legacy.

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

Signature​

export interface IDeltaHandler

Properties​

Property Alerts Type Description
processMessages Alpha (messageCollection: IRuntimeMessageCollection) => void Process messages for this channel. The messages here are contiguous messages for this channel in a batch.

Methods​

Method Alerts Modifiers Return Type Description
applyStashedOp(message) Alpha void Apply changes from an op just as if a local client has made the change, including submitting the op. Used when rehydrating an attached container with pending changes. This prepares the SharedObject for seeing an ACK for the op or resubmitting the op upon reconnection.
reSubmit(message, localOpMetadata, squash) Alpha void Called when the runtime asks the client to resubmit an op. This may be because the Container reconnected and this op was not acked. The client can choose to resubmit the same message, submit different / multiple messages or not submit anything at all.
rollback(message, localOpMetadata) Alpha optional void Revert a local op.
setConnectionState(connected) Alpha void State change events to indicate changes to the delta connection

Property Details​

processMessages​

Process messages for this channel. The messages here are contiguous messages for this channel in a batch.

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​
processMessages: (messageCollection: IRuntimeMessageCollection) => void;

Type: (messageCollection: IRuntimeMessageCollection) => void

Method Details​

applyStashedOp​

Apply changes from an op just as if a local client has made the change, including submitting the op. Used when rehydrating an attached container with pending changes. This prepares the SharedObject for seeing an ACK for the op or resubmitting the op upon reconnection.

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​
applyStashedOp(message: any): void;

Parameters​

Parameter Type Description
message any

Returns​

Should return void.

reSubmit​

Called when the runtime asks the client to resubmit an op. This may be because the Container reconnected and this op was not acked. The client can choose to resubmit the same message, submit different / multiple messages or not submit anything at all.

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​
reSubmit(message: any, localOpMetadata: unknown, squash?: boolean): void;

Parameters​

Parameter Modifiers Type Description
message any The original message that was submitted.
localOpMetadata unknown The local metadata associated with the original message.
squash optional boolean If true, the DDS should avoid resubmitting any "unnecessary intermediate state" created by this message. This includes any content which this message created but has since been changed or removed by subsequent messages. For example, if this message (call it A) inserts content into a DDS that a subsequent op (call it B) removes, resubmission of this message (call it A') should avoid inserting that content, and resubmission of the subsequent op that removed it (B') would account for the fact that A' never inserted content.

rollback​

Revert a local op.

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​
rollback?(message: any, localOpMetadata: unknown): void;

Parameters​

Parameter Type Description
message any The original message that was submitted.
localOpMetadata unknown The local metadata associated with the original message.

setConnectionState​

State change events to indicate changes to the delta connection

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​
setConnectionState(connected: boolean): void;

Parameters​

Parameter Type Description
connected boolean true if connected, false otherwise