types.ts

export interface JsonRpcRequest<T extends unknown[] = unknown[]> {
  method: string
  id?: string
  params?: T
}

export type JsonRpcError = {
  name?: string
  code: number
  message: string
}

export type JsonRpcResponse<T extends unknown = unknown> =
  & ({
    result: T | null
  } | { error: JsonRpcError | null })
  & { jsonrpc?: '2.0'; id: string | null }

export type ClientAdded = <T extends unknown[] = unknown[]>(
  params: T,
  socket: WebSocket,
) => Promise<{ error: JsonRpcError } | string | null>

export type RPCOptions = Partial<{
  /**
   * Creates an ID for a specific client.
   *
   * If `{ error: ErrorResponse }` is returned, the client will be sent that error and the connection will be closed.
   *
   * If a `string` is returned, it will become the client's ID
   *
   * If `null` is returned, or if this function is not specified, the `clientId` will be set to a uuid
   */
  clientAdded: ClientAdded
  /**
   * Called when a socket is closed.
   */
  clientRemoved(clientId: string): Promise<void> | void
  /**
   * The path to listen for connections at.
   * If '*' is specified, all incoming ws requests will be used
   * @default '/' // upgrade all connections
   */
  path: string
  /**
   * Timeout
   */
  timeout: number
}>