import {TCPConnection} from 'eventstore-ts-client/src/eventstore/TCPConnection.ts'

public class | source

TCPConnection

Extends:

events~EventEmitter → TCPConnection

Raw tcp communication to eventstore This class handles basic communication with eventstore

Constructor Summary

Public Constructor
public	constructor() Creates an instance of TCPConnection.

Member Summary

Public Members
public get	isConnected: boolean Returns true if connected to eventstore otherwise false
public	log: bunyan logger instance

Protected Members
protected	connectionConfig: EventstoreSettings config after discovery process
protected	connectionId: string \| null connection id
protected	initialConfig: EventstoreSettings initial config
protected	isUnexpectedClosed: boolean indicates if connection close is wanted by user or not
protected	messageCurrentLength: number message length of tcp data
protected	messageCurrentOffset: number message offset of tcp data
protected	messageData: Buffer \| null message buffer of tcp data
protected	pendingRequests: Map list of pending requests
protected	persistentSubscriptionList: Map list of persistent subscriptions
protected	reconnectCount: number counter for re-connections
protected	socket: SOMEUNKNOWN \| SOMEUNKNOWN tcp socket
protected	state: connectionState connection state
protected	subscriptionList: Map list of subscriptions
protected	timeoutInterval: null \| SOMEUNKNOWN timeout interval for timed out pending requests

Method Summary

Public Methods
public	async connect(): Promise Called to connect to eventstore
public	async connectToPersistentSubscription(subscription: PersistentSubscription, allowedInFlightMessages: number, credentials: UserCredentials \| null): Promise Connects to persistent subscription
public	async disconnect(): Promise Disconnect from eventstore.
public	sendCommand(correlationId: , command: EventstoreCommand, data: Buffer \| null, credentials: UserCredentials \| null, promise: null): void Creates and sends raw data message to eventstore and adds given promise to pending queue
public	subscribeToStream(stream: Stream, resolveLinkTos: boolean, credentials: UserCredentials \| null): Promise Subscribes to stream
public	async unsubscribeFromPersistentSubscription(subscriptionId: , credentials: UserCredentials \| null): Promise Stop listening on persistent subscription
public	async unsubscribeFromStream(subscriptionId: ): Promise Unsubscribes from stream

Protected Methods
protected	checkOperationResult(correlationId: , result: , message: string): boolean CHecks if given result is an error code It returns true for successful result otherwise it returns false.
protected	checkTimeout(): void Called by interval function to check if there are some pending requests which should be rejected with time out error
protected	handleCreatePersistentSubscriptionCompleted(correlationId: , payload: Buffer): void Handle response for command CreatePersistentSubscription
protected	handleDeletePersistentSubscriptionCompleted(correlationId: , payload: Buffer): void Handle response for command DeletePersistentSubscription
protected	handleDeleteStreamCompleted(correlationId: , payload: Buffer): void Handle response for command DeleteStreamCompleted
protected	handleMultiPacketResponseData(data: Buffer): Buffer \| null This function handles raw buffer responses received within multiple tcp data package
protected	handleNewResponseData(data: Buffer): Buffer \| null Gets called as soon as new data over tcp connection arrives as raw buffer data Checks if new received data is part of previously received data new data contains multiple responses new data is single response
protected	handlePersistentSubscriptionConfirmation(correlationId: , payload: Buffer): void Handles persistent subscription confirmation
protected	handlePersistentSubscriptionStreamEventAppeared(correlationId: , payload: Buffer): void Handles persistent subscription stream event appeared
protected	handleReadAllEventsCompleted(correlationId: , payload: Buffer): void Handle response for command ReadAllEvents
protected	handleReadEventCompleted(correlationId: , payload: Buffer): void Handle response for command ReadEvent
protected	handleReadStreamEventsCompleted(correlationId: , payload: Buffer): void Handle response for command ReadStreamEvents
protected	handleSingleResponseData(data: Buffer): void This function handles a single raw buffer response
protected	handleStreamEventAppeared(correlationId: , payload: Buffer): void Handle incoming event for subscription
protected	handleSubscriptionConfirmation(correlationId: , payload: Buffer): void Handle response for command Subscription
protected	handleSubscriptionDropped(correlationId: , payload: Buffer): void Handle subscription drop
protected	handleTransactionCommitCompleted(correlationId: , payload: Buffer): void Handle response for command TransactionCommit
protected	handleTransactionStartCompleted(correlationId: , payload: Buffer): void Handle response for command TransactionStart
protected	handleTransactionWriteCompleted(correlationId: , payload: Buffer): void Handles transaction write completed
protected	handleUpdatePersistentSubscriptionCompleted(correlationId: , payload: Buffer): void Handles update persistent subscription completed
protected	handleWriteEventsCompleted(correlationId: , payload: Buffer): void Handles write events completed
protected	onClose(): void Emit as soon as connection to eventstore is closed
protected	onConnect(): void Emit as soon as connection to eventstore was established successfully
protected	onData(data: Buffer \| null): void Emitted as soon as data arrives over tcp connection
protected	onDrain(): void Emit when connection starts draining
protected	onError(err: Error): void Emit general low level connection errors (communication errors).
protected	onSecureConnect(): void Emit when connection secured
protected	rejectCommandPromise(correlationId: , error: ): void Will be called if a command send to eventstore was replied with an error In this case corresponding promise will be rejected and removed from queue
protected	resolveCommandPromise(correlationId: , result: null \| T): void Will be called if a command send to eventstore was replied with success response In this case corresponding promise will be resolved with result received from eventstore
protected	async tryToConnect(): Promise Connect to eventstore

Public Constructors

public constructor() source

Creates an instance of TCPConnection.

Public Members

public get isConnected: boolean source

Returns true if connected to eventstore otherwise false

public log: bunyan source

logger instance

Protected Members

protected connectionConfig: EventstoreSettings source

config after discovery process

protected connectionId: string | null source

connection id

protected initialConfig: EventstoreSettings source

initial config

protected isUnexpectedClosed: boolean source

indicates if connection close is wanted by user or not

protected messageCurrentLength: number source

message length of tcp data

protected messageCurrentOffset: number source

message offset of tcp data

protected messageData: Buffer | null source

message buffer of tcp data

protected pendingRequests: Map source

list of pending requests

protected persistentSubscriptionList: Map source

list of persistent subscriptions

protected reconnectCount: number source

counter for re-connections

protected socket: SOMEUNKNOWN | SOMEUNKNOWN source

tcp socket

protected state: connectionState source

connection state

protected subscriptionList: Map source

list of subscriptions

protected timeoutInterval: null | SOMEUNKNOWN source

timeout interval for timed out pending requests

Public Methods

public async connect(): Promise source

Called to connect to eventstore

public async connectToPersistentSubscription(subscription: PersistentSubscription, allowedInFlightMessages: number, credentials: UserCredentials | null): Promise source

Connects to persistent subscription

Params:

Name	Type	Attribute	Description
subscription	PersistentSubscription
allowedInFlightMessages	number	optional default: 10
credentials	UserCredentials \| null

public async disconnect(): Promise source

Disconnect from eventstore. It tries to drain pending queue to prevent data loose before connection gets closed If disconnect() is call no new outgoing requests accepted

public sendCommand(correlationId: , command: EventstoreCommand, data: Buffer | null, credentials: UserCredentials | null, promise: null): void source

Creates and sends raw data message to eventstore and adds given promise to pending queue

Params:

Name	Type	Attribute	Description
correlationId
command	EventstoreCommand
data	Buffer \| null	optional default: null
credentials	UserCredentials \| null	optional default: null
promise	null	optional default: null

public subscribeToStream(stream: Stream, resolveLinkTos: boolean, credentials: UserCredentials | null): Promise source

Subscribes to stream

Params:

Name	Type	Attribute	Description
stream	Stream
resolveLinkTos	boolean	optional default: true
credentials	UserCredentials \| null

public async unsubscribeFromPersistentSubscription(subscriptionId: , credentials: UserCredentials | null): Promise source

Stop listening on persistent subscription

Params:

Name	Type	Attribute	Description
subscriptionId
credentials	UserCredentials \| null

public async unsubscribeFromStream(subscriptionId: ): Promise source

Unsubscribes from stream

Params:

Name	Type	Attribute	Description
subscriptionId

Protected Methods

protected checkOperationResult(correlationId: , result: , message: string): boolean source

CHecks if given result is an error code It returns true for successful result otherwise it returns false. If result is an error this function rejects corresponding command promise and remove it from command queue

Params:

Name	Type	Attribute	Description
correlationId
result
message	string	optional default:

protected checkTimeout(): void source

Called by interval function to check if there are some pending requests which should be rejected with time out error

protected handleCreatePersistentSubscriptionCompleted(correlationId: , payload: Buffer): void source

Handle response for command CreatePersistentSubscription

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleDeletePersistentSubscriptionCompleted(correlationId: , payload: Buffer): void source

Handle response for command DeletePersistentSubscription

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleDeleteStreamCompleted(correlationId: , payload: Buffer): void source

Handle response for command DeleteStreamCompleted

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleMultiPacketResponseData(data: Buffer): Buffer | null source

This function handles raw buffer responses received within multiple tcp data package

Params:

Name	Type	Attribute	Description
data	Buffer

protected handleNewResponseData(data: Buffer): Buffer | null source

Gets called as soon as new data over tcp connection arrives as raw buffer data Checks if

new received data is part of previously received data
new data contains multiple responses
new data is single response

Params:

Name	Type	Attribute	Description
data	Buffer

protected handlePersistentSubscriptionConfirmation(correlationId: , payload: Buffer): void source

Handles persistent subscription confirmation

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handlePersistentSubscriptionStreamEventAppeared(correlationId: , payload: Buffer): void source

Handles persistent subscription stream event appeared

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleReadAllEventsCompleted(correlationId: , payload: Buffer): void source

Handle response for command ReadAllEvents

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleReadEventCompleted(correlationId: , payload: Buffer): void source

Handle response for command ReadEvent

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleReadStreamEventsCompleted(correlationId: , payload: Buffer): void source

Handle response for command ReadStreamEvents

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleSingleResponseData(data: Buffer): void source

This function handles a single raw buffer response

Params:

Name	Type	Attribute	Description
data	Buffer

protected handleStreamEventAppeared(correlationId: , payload: Buffer): void source

Handle incoming event for subscription

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleSubscriptionConfirmation(correlationId: , payload: Buffer): void source

Handle response for command Subscription

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleSubscriptionDropped(correlationId: , payload: Buffer): void source

Handle subscription drop

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleTransactionCommitCompleted(correlationId: , payload: Buffer): void source

Handle response for command TransactionCommit

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleTransactionStartCompleted(correlationId: , payload: Buffer): void source

Handle response for command TransactionStart

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleTransactionWriteCompleted(correlationId: , payload: Buffer): void source

Handles transaction write completed

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleUpdatePersistentSubscriptionCompleted(correlationId: , payload: Buffer): void source

Handles update persistent subscription completed

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected handleWriteEventsCompleted(correlationId: , payload: Buffer): void source

Handles write events completed

Params:

Name	Type	Attribute	Description
correlationId
payload	Buffer

protected onClose(): void source

Emit as soon as connection to eventstore is closed

protected onConnect(): void source

Emit as soon as connection to eventstore was established successfully

protected onData(data: Buffer | null): void source

Emitted as soon as data arrives over tcp connection

Params:

Name	Type	Attribute	Description
data	Buffer \| null

protected onDrain(): void source

Emit when connection starts draining

protected onError(err: Error): void source

Emit general low level connection errors (communication errors). Will not emit errors on business level

Params:

Name	Type	Attribute	Description
err	Error

protected onSecureConnect(): void source

Emit when connection secured

protected rejectCommandPromise(correlationId: , error: ): void source

Will be called if a command send to eventstore was replied with an error In this case corresponding promise will be rejected and removed from queue

Params:

Name	Type	Attribute	Description
correlationId
error

protected resolveCommandPromise(correlationId: , result: null | T): void source

Will be called if a command send to eventstore was replied with success response In this case corresponding promise will be resolved with result received from eventstore

Params:

Name	Type	Attribute	Description
correlationId
result	null \| T	optional default: null

protected async tryToConnect(): Promise source

Connect to eventstore