Class BaseEventSource`Abstract`

Base class for EventSource implementation

Implement BaseSource 101:

extends this class
constructor(url, eventSourceInitDict) :
- take url as first argument
- an eventSourceInitDict as second argument, for request options
- merge EVENT_STREAM_HEADERS EVENT_STREAM_HEADERS in eventSourceInitDict.headers
- run the request
- on response :
  - store resources to clean later
  - use isValidResponse
    - if not valid call handleInvalidResponse and cleanup opened resources (request / response)
    - if valid
      - signalOpen
      - Adapt the response to the EventSource api
      - Your response body should be a stream (lazyness fetching / parsing / transform)
      - const stream = response.pipe(createEventStreamTransform()) :createEventStreamTransform
      - this.initStreamAdaptor(stream, this.cleaning) initStreamAdaptor
cleaning() clean resources stored and unassign them

See

https://html.spec.whatwg.org/multipage/server-sent-events.html#the-eventsource-interface for the spec

Note for reader on typedoc, activate Protected member visibility, by default only Inherited is selected

Hierarchy

EventTarget
- BaseEventSource
  - Node.EventSource
  - Undici.EventSource

Index

Constructors

`Protected` constructor

new BaseEventSource(url: string): BaseEventSource
Parameters
- url: string
Returns BaseEventSource
Overrides EventTarget.constructor
- Defined in src/BaseEventSource.ts:48

Properties

`Protected` _readyState

_readyState: undefined | number

onerror

onerror: undefined | ((event: Event) => void)

onmessage

onmessage: undefined | ((event: Event) => void)

onopen

onopen: undefined | ((event: Event) => void)

`Readonly` url

url: string

`Static` `Readonly` CLOSED

CLOSED: CLOSED = ReadyState.CLOSED

`Static` `Readonly` CONNECTING

CONNECTING: CONNECTING = ReadyState.CONNECTING

`Static` `Readonly` OPEN

OPEN: OPEN = ReadyState.OPEN

Accessors

readyState

get readyState(): undefined | number
Returns undefined | number
- Defined in src/BaseEventSource.ts:61

Methods

addEventListener

addEventListener(type: string, listener: EventListener | EventListenerObject, options?: boolean | AddEventListenerOptions): void
Adds a new handler for the type event. Any given listener is added only once per type and per capture option value.

If the once option is true, the listener is removed after the next time a type event is dispatched.

The capture option is not used by Node.js in any functional way other than tracking registered event listeners per the EventTarget specification. Specifically, the capture option is used as part of the key when registering a listener. Any individual listener may be added once with capture = false, and once with capture = true.
Parameters
- type: string
- listener: EventListener | EventListenerObject
- Optional options: boolean | AddEventListenerOptions
Returns void
Inherited from EventTarget.addEventListener
- Defined in node_modules/@types/node/ts4.8/dom-events.d.ts:63

`Protected` `Abstract` cleaning

cleaning(): void

MUST be implemented by child class

Example

protected cleaning() {
  // clean resources
  // ex
  this.#request?.destroy();
  this.#request = undefined;
}

Returns void

close

close(): void
Returns void
- Defined in src/BaseEventSource.ts:70

dispatchEvent

dispatchEvent(event: Event): boolean
Dispatches a synthetic event event to target and returns true if either event's cancelable attribute value is false or its preventDefault() method was not invoked, and false otherwise.
Parameters
- event: Event
Returns boolean
Inherited from EventTarget.dispatchEvent
- Defined in node_modules/@types/node/ts4.8/dom-events.d.ts:69

`Protected` handleInvalidResponse

handleInvalidResponse(): void
Protected
build an error attach to an event error and dispatch the event

Returns void
- Defined in src/BaseEventSource.ts:118

`Protected` `Abstract` init

init(url: string): void
MUST be implemented by child class
Parameters
- url: string
Returns void
- Defined in src/BaseEventSource.ts:78

`Protected` initStreamAdaptor

initStreamAdaptor(stream: TransformParser, onErrorCleanUp: (() => void)): void
Protected
- listen error on stream to signal in EventTarget way
- listen on data on stream to signal it EventTarget way (message, named event)
Parameters
- stream: TransformParser
- onErrorCleanUp: (() => void)
  - - (): void
    - Returns void
Returns void
- Defined in src/BaseEventSource.ts:185

`Protected` isValidResponse

isValidResponse(response: {
headers?: IncomingHttpHeaders;
statusCode?: number;
}): boolean
Protected
Check if response 200 or Content-Type is text/event-stream
Parameters
- response: {
  headers?: IncomingHttpHeaders;
  statusCode?: number;
  }
  - Optional headers?: IncomingHttpHeaders
  - Optional statusCode?: number
Returns boolean
- Defined in src/BaseEventSource.ts:104

removeEventListener

removeEventListener(type: string, listener: EventListener | EventListenerObject, options?: boolean | EventListenerOptions): void
Removes the event listener in target's event listener list with the same type, callback, and options.
Parameters
- type: string
- listener: EventListener | EventListenerObject
- Optional options: boolean | EventListenerOptions
Returns void
Inherited from EventTarget.removeEventListener
- Defined in node_modules/@types/node/ts4.8/dom-events.d.ts:71

`Protected` signalError

signalError(error: Error): void
Dispatch an event error
Parameters
- error: Error
Returns void
- Defined in src/BaseEventSource.ts:143

`Protected` signalEvent

signalEvent(_event: IEvent): void
Check if IEvent is named (prop event: string) Dispatch it
Parameters
- _event: IEvent
Returns void
- Defined in src/BaseEventSource.ts:169

`Protected` signalMessage

signalMessage(_event: IEvent): void
Dispatch a message with an IEvent and try to dispatch named event from message event
Parameters
- _event: IEvent
Returns void
- Defined in src/BaseEventSource.ts:156

`Protected` signalOpen

signalOpen(): void
Protected
Dispatch open event

Returns void
- Defined in src/BaseEventSource.ts:133

Class BaseEventSourceAbstract

See

Hierarchy

Index

Constructors

Properties

Accessors

Methods

Constructors

Protected constructor

Parameters

url: string

Returns BaseEventSource

Properties

Protected _readyState

onerror

onmessage

onopen

Readonly url

Static Readonly CLOSED

Static Readonly CONNECTING

Static Readonly OPEN

Accessors

readyState

Returns undefined | number

Methods

addEventListener

Parameters

type: string

listener: EventListener | EventListenerObject

Optional options: boolean | AddEventListenerOptions

Returns void

Protected Abstract cleaning

Example

Returns void

close

Returns void

dispatchEvent

Parameters

event: Event

Returns boolean

Protected handleInvalidResponse

Returns void

Protected Abstract init

Parameters

url: string

Returns void

Protected initStreamAdaptor

Parameters

stream: TransformParser

onErrorCleanUp: (() => void)

Returns void

Returns void

Protected isValidResponse

Parameters

response: { headers?: IncomingHttpHeaders; statusCode?: number; }

Optional headers?: IncomingHttpHeaders

Optional statusCode?: number

Returns boolean

removeEventListener

Parameters

type: string

listener: EventListener | EventListenerObject

Optional options: boolean | EventListenerOptions

Returns void

Protected signalError

Parameters

error: Error

Returns void

Protected signalEvent

Parameters

_event: IEvent

Returns void

Protected signalMessage

Parameters

_event: IEvent

Returns void

Protected signalOpen

Returns void

Settings

Class BaseEventSource`Abstract`

`Protected` constructor

`Protected` _readyState

`Readonly` url

`Static` `Readonly` CLOSED

`Static` `Readonly` CONNECTING

`Static` `Readonly` OPEN

`Optional` options: boolean | AddEventListenerOptions

`Protected` `Abstract` cleaning

`Protected` handleInvalidResponse

`Protected` `Abstract` init

`Protected` initStreamAdaptor

`Protected` isValidResponse

response: {
headers?: IncomingHttpHeaders;
statusCode?: number;
}

`Optional` headers?: IncomingHttpHeaders

`Optional` statusCode?: number

`Optional` options: boolean | EventListenerOptions

`Protected` signalError

`Protected` signalEvent

`Protected` signalMessage

`Protected` signalOpen