Define minimal user message middleware.

src/app/store.ts

@@ -12,6 +12,7 @@ import { roomSocketMessageMiddleware } from "modules/room/message";
 import roomReducer from "modules/room/slice";
 import makeSocketMiddleware from "modules/socket/middleware";
 import socketReducer from "modules/socket/slice";
+import { userSocketMessageMiddleware } from "modules/user/message";
 import userReducer from "modules/user/slice";
 
 const rootReducer = combineReducers({
@@ -35,6 +36,7 @@ export const store = configureStore({
       makeSocketMiddleware([
         loginSocketMessageMiddleware,
         roomSocketMessageMiddleware,
+        userSocketMessageMiddleware,
       ])
     ),
 });

src/modules/room/message.ts

@@ -1,9 +1,6 @@
 import { AppDispatch } from "app/store";
 import { roomMessage, roomGetAll, roomSetAll } from "modules/room/slice";
-import {
-  SocketMessage,
-  SocketMessageMiddleware,
-} from "modules/websocket/message";
+import { SocketMessage, SocketMessageMiddleware } from "modules/socket/message";
 
 function roomListRequest(): SocketMessage {
   return {

src/modules/user/message.ts

@@ -0,0 +1,41 @@
+import { AppDispatch } from "app/store";
+import { userGetAll, userSetAll } from "modules/user/slice";
+import { SocketMessage, SocketMessageMiddleware } from "modules/socket/message";
+
+function userListRequest(): SocketMessage {
+  return {
+    variant: "UserListRequest",
+    fields: [],
+  };
+}
+
+function handleUserListResponse(dispatch: AppDispatch, outerFields: any[]) {
+  if (outerFields.length !== 1) {
+    console.log("UserListResponse has wrong number of fields:", outerFields);
+    return;
+  }
+
+  const { users } = outerFields[0];
+  if (users === undefined) {
+    console.log("UserListResponse field has wrong shape:", outerFields[0]);
+    return;
+  }
+
+  dispatch(userSetAll(users));
+}
+
+export const userSocketMessageMiddleware: SocketMessageMiddleware = {
+  handleMessage: (dispatch, { variant, fields }) => {
+    switch (variant) {
+      case "UserListResponse":
+        handleUserListResponse(dispatch, fields);
+        break;
+    }
+  },
+
+  handleAction: (send, action) => {
+    if (userGetAll.match(action)) {
+      send(userListRequest());
+    }
+  },
+};