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LCU Socket observation

This namespace helps you to observe specific LCU APIs without creating a new WebSocket. You cannot get it directly from window, instead use the context of the init entry point.

socket.observe(api, listener)

functionsince v1.1.0
function observe(
  api: string,
  listener: ApiListener
): { disconnect: () => void }

interface EventData {
  data: any
  uri: string
  eventType: 'Create' | 'Update' | 'Delete'

interface ApiListener {
  (message: EventData): void

Subscribe a listener to listen when the given API endpoint get called.


  • api a string that presents a LCU API endpoint.
  • listener a function that gets called with one data param.

Return value:

An object with a prop disconnect that could be called to disconnect the observer.


socket.observe('/lol-matchmaking/v1/ready-check', (data) => {

socket.disconnect(api, listener)

functionsince v1.1.0
function disconnect(api: string, listener: ApiListener)

Disconnect a subscribed listener. The function parameters like the function above.

Released under the WTF License.