useEventSource

類別

導出大小

1.02 kB

上次變更

5 天前

一個 EventSource 或 Server-Sent-Events 實例開啟與 HTTP 伺服器的持久連線，該伺服器以 text/event-stream 格式傳送事件。

用法

import { useEventSource } from '@vueuse/core'

const { status, data, error, close } = useEventSource('https://event-source-url')

請參閱類型宣告以了解更多選項。

命名事件

您可以使用第二個參數定義命名事件

TypeScript

import { useEventSource } from '@vueuse/core'

const { event, data } = useEventSource('https://event-source-url', ['notice', 'update'] as const)

import { useEventSource } from '@vueuse/core'
const { event, data } = useEventSource('https://event-source-url', [
  'notice',
  'update',
])

immediate

預設啟用。

在呼叫 composable 時立即建立連線。

autoConnect

預設啟用。

如果 url 作為 ref 提供，當 url 變更時，它將自動重新連線到新的 url。

錯誤時自動重新連線

在發生錯誤時自動重新連線（預設停用）。

const { status, data, close } = useEventSource('https://event-source-url', [], {
  autoReconnect: true,
})

或使用更多控制其行為的方式

const { status, data, close } = useEventSource('https://event-source-url', [], {
  autoReconnect: {
    retries: 3,
    delay: 1000,
    onFailed() {
      alert('Failed to connect EventSource after 3 retries')
    },
  },
})

類型宣告

顯示類型宣告

typescript

export type EventSourceStatus = "CONNECTING" | "OPEN" | "CLOSED"
export interface UseEventSourceOptions extends EventSourceInit {
  /**
   * Enabled auto reconnect
   *
   * @default false
   */
  autoReconnect?:
    | boolean
    | {
        /**
         * Maximum retry times.
         *
         * Or you can pass a predicate function (which returns true if you want to retry).
         *
         * @default -1
         */
        retries?: number | (() => boolean)
        /**
         * Delay for reconnect, in milliseconds
         *
         * @default 1000
         */
        delay?: number
        /**
         * On maximum retry times reached.
         */
        onFailed?: Fn
      }
  /**
   * Immediately open the connection when calling this composable
   *
   * @default true
   */
  immediate?: boolean
  /**
   * Automatically connect to the websocket when URL changes
   *
   * @default true
   */
  autoConnect?: boolean
}
export interface UseEventSourceReturn<Events extends string[], Data = any> {
  /**
   * Reference to the latest data received via the EventSource,
   * can be watched to respond to incoming messages
   */
  data: ShallowRef<Data>
  /**
   * The current state of the connection, can be only one of:
   * 'CONNECTING', 'OPEN' 'CLOSED'
   */
  status: ShallowRef<EventSourceStatus>
  /**
   * The latest named event
   */
  event: ShallowRef<Events[number] | null>
  /**
   * The current error
   */
  error: ShallowRef<Event | null>
  /**
   * Closes the EventSource connection gracefully.
   */
  close: EventSource["close"]
  /**
   * Reopen the EventSource connection.
   * If there the current one is active, will close it before opening a new one.
   */
  open: Fn
  /**
   * Reference to the current EventSource instance.
   */
  eventSource: Ref<EventSource | null>
  /**
   * The last event ID string, for server-sent events.
   * @see https://developer.mozilla.org/en-US/docs/Web/API/MessageEvent/lastEventId
   */
  lastEventId: ShallowRef<string | null>
}
/**
 * Reactive wrapper for EventSource.
 *
 * @see https://vueuse.dev.org.tw/useEventSource
 * @see https://developer.mozilla.org/en-US/docs/Web/API/EventSource/EventSource EventSource
 * @param url
 * @param events
 * @param options
 */
export declare function useEventSource<Events extends string[], Data = any>(
  url: MaybeRefOrGetter<string | URL | undefined>,
  events?: Events,
  options?: UseEventSourceOptions,
): UseEventSourceReturn<Events>