Add missing types in cross-origin-rpc.js

src/sidebar/cross-origin-rpc.js

@@ -6,14 +6,17 @@ import { normalizeGroupIds } from './helpers/groups';
  * @typedef {import('../types/rpc').FocusUserInfo} FocusUserInfo
  */
 
-// Array to keep track of pre-start requests
+/**
+ * List of not-yet-processed messages received during application startup.
+ *
+ * @type {MessageEvent[]}
+ */
 let preStartQueue = [];
 
 /**
  * Return the mapped methods that can be called remotely via this server.
  *
- * @param {object} store - The global store
- * @return {object}
+ * @param {import('./store').SidebarStore} store - The global store
  */
 const registeredMethods = store => {
   return {
@@ -31,10 +34,19 @@ const registeredMethods = store => {
   };
 };
 
+/**
+ * @typedef JSONRPCMessage
+ * @prop {string} jsonrpc
+ * @prop {string} id
+ * @prop {string} method
+ * @prop {unknown[]} params
+ */
+
 /**
  * Return true if `data` "looks like" a JSON-RPC message.
  *
  * @param {any} data
+ * @return {data is JSONRPCMessage}
  */
 function isJsonRpcMessage(data) {
   // eslint-disable-next-line eqeqeq
@@ -62,9 +74,14 @@ function isJsonRpcMessage(data) {
  * notifications) and sending back a successful "ok" response.
  *
  * All methods called upon must be mapped in the `registeredMethods` function.
+ *
+ * @param {import('./store').SidebarStore} store
+ * @param {import('../types/config').SidebarSettings} settings
+ * @param {Window} $window
+ * @inject
  */
-// @inject
 export function startServer(store, settings, $window) {
+  /** @type {Record<string, (...args: any[]) => void>} */
   const methods = registeredMethods(store);
 
   // Process the pre-start incoming RPC requests
@@ -78,6 +95,7 @@ export function startServer(store, settings, $window) {
   // Start listening to new RPC requests
   $window.addEventListener('message', receiveMessage);
 
+  /** @param {MessageEvent} event */
   function receiveMessage(event) {
     let allowedOrigins = settings.rpcAllowedOrigins || [];
 
@@ -96,10 +114,15 @@ export function startServer(store, settings, $window) {
     // data param.
     let jsonRpcRequest = event.data;
 
-    event.source.postMessage(jsonRpcResponse(jsonRpcRequest), event.origin);
+    const source = /** @type {Window} */ (event.source);
+    source.postMessage(jsonRpcResponse(jsonRpcRequest), event.origin);
   }
 
-  /** Return a JSON-RPC response to the given JSON-RPC request object. */
+  /**
+   * Return a JSON-RPC response to the given JSON-RPC request object.
+   *
+   * @param {JSONRPCMessage} request
+   */
   function jsonRpcResponse(request) {
     const method = methods[request.method];