ConsensusRegisterCollectionClass Class

A distributed data structure that holds a set of registers with update versions. On concurrent updates, a register internally stores all possible versions of a value by using reference sequence number of the incoming update.

Using all the stored versions, we can then distinguish amongst different read policies. Below are the policies we support:

Atomic: Atomicity requires a linearizable register. A linearizable register behaves as if there is only a single copy of the data, and that every operation appears to take effect atomically at one point in time. This definition implies that operations are executed in an well-defined order. On a concurrent update, we perform a compare-and-set operation, where we compare a register sequence number with the incoming reference sequence number. The earliest operation overwriting prior sequence numbers wins since every client reaches to an agreement on the value. So we can safely return the first value.

LWW: The last write to a key always wins.

This API is deprecated and will be removed in a future release.

Use IConsensusRegisterCollection for typing and ConsensusRegisterCollectionFactory to create instances. This implementation class will be removed in a future release.

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

To use, import via @fluidframework/register-collection/legacy.

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

Signature

export declare class ConsensusRegisterCollection<T> extends SharedObject<IConsensusRegisterCollectionEvents> implements IConsensusRegisterCollection<T>

Extends: SharedObject<IConsensusRegisterCollectionEvents>

Implements: IConsensusRegisterCollection<T>

Type Parameters

Parameter	Description
T

Constructors

Constructor	Alerts	Description
(constructor)(id, runtime, attributes)	Beta	Constructs a new consensus register collection. If the object is non-local an id and service interfaces will be provided

Methods

Method	Alerts	Modifiers	Return Type	Description
applyStashedOp(content)	Beta		void
keys()	Beta		string[]
loadCore(storage)	Beta		Promise<void>
onDisconnect()	Beta		void
processMessagesCore(messagesCollection)	Beta		void
read(key, readPolicy)	Beta		T | undefined	Returns the most recent local value of a register.
readVersions(key)	Beta		T[] | undefined
rollback(content, localOpMetadata)	Beta	sealed	void
summarizeCore(serializer)	Beta		ISummaryTreeWithStats
write(key, value)	Beta		Promise<boolean>	Creates a new register or writes a new value. Returns a promise that will resolve when the write is acked.

Constructor Details

(constructor)

Constructs a new consensus register collection. If the object is non-local an id and service interfaces will be provided

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);

Parameters

Parameter	Type	Description
id	string
runtime	IFluidDataStoreRuntime
attributes	IChannelAttributes

Method Details

applyStashedOp

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 applyStashedOp(content: unknown): void;

Parameters

Parameter	Type	Description
content	unknown

keys

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

keys(): string[];

Returns

Return type: string[]

loadCore

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 loadCore(storage: IChannelStorageService): Promise<void>;

Parameters

Parameter	Type	Description
storage	IChannelStorageService

Returns

Return type: Promise<void>

onDisconnect

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 onDisconnect(): void;

processMessagesCore

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 processMessagesCore(messagesCollection: IRuntimeMessageCollection): void;

Parameters

Parameter	Type	Description
messagesCollection	IRuntimeMessageCollection

read

Returns the most recent local value of a register.

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

read(key: string, readPolicy?: ReadPolicy): T | undefined;

Parameters

Parameter	Modifiers	Type	Description
key		string	The key to read
readPolicy	optional	ReadPolicy	The ReadPolicy to apply. Defaults to Atomic.

Returns

Return type: T | undefined

readVersions

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

readVersions(key: string): T[] | undefined;

Parameters

Parameter	Type	Description
key	string

Returns

Return type: T[] | undefined

rollback

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

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

Sealed

This type is "sealed," meaning that code outside of the library defining it should not implement or extend it. Future versions of this type may add members or make typing of readonly members more specific.

Signature

/** @sealed */
protected rollback(content: unknown, localOpMetadata: unknown): void;

Parameters

Parameter	Type	Description
content	unknown
localOpMetadata	unknown

summarizeCore

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 summarizeCore(serializer: IFluidSerializer): ISummaryTreeWithStats;

Parameters

Parameter	Type	Description
serializer	IFluidSerializer

Returns

Return type: ISummaryTreeWithStats

write

Creates a new register or writes a new value. Returns a promise that will resolve when the write is acked.

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

write(key: string, value: T): Promise<boolean>;

Parameters

Parameter	Type	Description
key	string
value	T

Returns

Promise if write was non-concurrent

Return type: Promise<boolean>