Dispatch received messages to handlers. This utility assumes messages are one of three types: request, response, or notification; and follow this format:
interface Request {
from: string
to: string
type: "request"
id: string
method: string
args?: Record<string, unknown>
}
interface Notification {
from: string
to: string
type: "notification"
method: string
args?: Record<string, unknown>
}
interface Response {
from: string
to: string
type: "response"
id: string
error: unknown
result: unknown
}Call dispatch to dispatch a received message. Only messages whose from and to attributes match those of the dispatcher will be processed.
Requests and notifications are dispatched to handlers provided during construction, while responses are dispatched to response listeners. To listen for a response, call waitForResponse with the request ID.
import { makeMessageDispatcher } from "@lsdsoftware/message-dispatcher"
const iframe1MessageDispatcher = makeMessageDispatcher({
from: "iframe1",
to: "main",
requestHandlers: {
method1(args, sender) {
//do something
return result
},
async method2(args, sender) {
//do something
return result
}
}
})
//process messages from iframe1
window.addEventListener("message", event => {
const sender = {window: event.source, origin: event.origin}
iframe1MessageDispatcher.dispatch({
message: event.data,
sender: sender,
sendResponse: response => sender.window.postMessage(response, sender.origin)
})
})
//send a request to iframe1
const id = String(Math.random())
const request = {
from: "main",
to: "iframe1",
type: "request",
id: id,
method: "someMethod",
args: {...}
}
iframe1.contentWindow.postMessage(request, "*")
iframe1MessageDispatcher.waitForResponse(id).then(result => console.log(result))