import { Transport } from "./shared/transport.js";
import { JSONRPCMessage } from "./types.js";
/**
* In-memory transport for creating clients and servers that talk to each other within the same process.
*/
export class InMemoryTransport implements Transport {
private _otherTransport?: InMemoryTransport;
private _messageQueue: JSONRPCMessage[] = [];
onclose?: () => void;
onerror?: (error: Error) => void;
onmessage?: (message: JSONRPCMessage) => void;
/**
* Creates a pair of linked in-memory transports that can communicate with each other. One should be passed to a Client and one to a Server.
*/
static createLinkedPair(): [InMemoryTransport, InMemoryTransport] {
const clientTransport = new InMemoryTransport();
const serverTransport = new InMemoryTransport();
clientTransport._otherTransport = serverTransport;
serverTransport._otherTransport = clientTransport;
return [clientTransport, serverTransport];
}
async start(): Promise<void> {
// Process any messages that were queued before start was called
while (this._messageQueue.length > 0) {
const message = this._messageQueue.shift();
if (message) {
this.onmessage?.(message);
}
}
}
async close(): Promise<void> {
const other = this._otherTransport;
this._otherTransport = undefined;
await other?.close();
this.onclose?.();
}
async send(message: JSONRPCMessage): Promise<void> {
if (!this._otherTransport) {
throw new Error("Not connected");
}
if (this._otherTransport.onmessage) {
this._otherTransport.onmessage(message);
} else {
this._otherTransport._messageQueue.push(message);
}
}
}