From 0dfef732bfa31b1e3bfe75be4e8fe9b349542134 Mon Sep 17 00:00:00 2001
From: Carlos Valente <carlosvalente@pm.me>
Date: Sun, 29 Dec 2024 20:30:10 +0100
Subject: [PATCH] refactor: prevent race conditions on init

---
 apps/server/src/app.ts                        |  7 +++++--
 .../message-service/MessageService.ts         | 15 ++++++++++---
 .../__tests__/MessageService.test.ts          | 21 ++++++++++---------
 apps/server/src/stores/EventStore.ts          |  1 +
 4 files changed, 29 insertions(+), 15 deletions(-)

diff --git a/apps/server/src/app.ts b/apps/server/src/app.ts
index 92f53f3c4..233e2f547 100644
--- a/apps/server/src/app.ts
+++ b/apps/server/src/app.ts
@@ -1,4 +1,4 @@
-import { LogOrigin, Playback, SimpleDirection, SimplePlayback } from 'ontime-types';
+import { LogOrigin, Playback, runtimeStorePlaceholder, SimpleDirection, SimplePlayback } from 'ontime-types';
 
 import 'dotenv/config';
 import express from 'express';
@@ -200,7 +200,7 @@ export const startServer = async (
     clock: state.clock,
     timer: state.timer,
     onAir: state.timer.playback !== Playback.Stop,
-    message: messageService.getState(),
+    message: { ...runtimeStorePlaceholder.message },
     runtime: state.runtime,
     eventNow: state.eventNow,
     currentBlock: {
@@ -224,6 +224,9 @@ export const startServer = async (
   const persistedCustomFields = getDataProvider().getCustomFields();
   initRundown(persistedRundown, persistedCustomFields);
 
+  // initialise message service
+  messageService.init(eventStore.set, eventStore.get);
+
   // load restore point if it exists
   const maybeRestorePoint = await restoreService.load();
 
diff --git a/apps/server/src/services/message-service/MessageService.ts b/apps/server/src/services/message-service/MessageService.ts
index 42e214d35..eec0c3266 100644
--- a/apps/server/src/services/message-service/MessageService.ts
+++ b/apps/server/src/services/message-service/MessageService.ts
@@ -2,12 +2,21 @@ import { MessageState, runtimeStorePlaceholder } from 'ontime-types';
 import { DeepPartial } from 'ts-essentials';
 
 import { throttle } from '../../utils/throttle.js';
-import { eventStore, type PublishFn } from '../../stores/EventStore.js';
+import type { StoreGetter, PublishFn } from '../../stores/EventStore.js';
 
 /**
  * Create a throttled version of the set function
  */
-const throttledSet: PublishFn = throttle(eventStore.set, 100);
+let throttledSet: PublishFn = () => undefined;
+let storeGet: StoreGetter = (_key: string) => undefined;
+
+/**
+ * Allows providing store interfaces
+ */
+export function init(storeSetter: PublishFn, storeGetter: StoreGetter) {
+  throttledSet = throttle(storeSetter, 100);
+  storeGet = storeGetter;
+}
 
 /**
  * Exposes function to reset the internal state
@@ -22,7 +31,7 @@ export function clear() {
  * Exposes the internal state of the message service
  */
 export function getState(): MessageState {
-  return eventStore.get('message');
+  return storeGet('message');
 }
 
 /**
diff --git a/apps/server/src/services/message-service/__tests__/MessageService.test.ts b/apps/server/src/services/message-service/__tests__/MessageService.test.ts
index d6c30916d..0ef7ef153 100644
--- a/apps/server/src/services/message-service/__tests__/MessageService.test.ts
+++ b/apps/server/src/services/message-service/__tests__/MessageService.test.ts
@@ -2,31 +2,32 @@ import * as messageService from '../MessageService.js';
 
 describe('MessageService', () => {
   beforeEach(() => {
+    // at runtime, the store is instantiated before the message service
+    const store = {};
+    const storeSetter = (key, value) => (store[key] = value);
+    const storeGetter = (key) => store[key];
+    messageService.init(storeSetter, storeGetter);
     messageService.clear();
   });
 
   it('should patch the message state', () => {
-    const message = {
+    const newState = messageService.patch({
       timer: { text: 'new text', visible: true },
       external: 'external',
-    };
+    });
 
-    const newState = messageService.patch(message);
-
-    expect(newState).toEqual({
+    expect(newState).toMatchObject({
       timer: { text: 'new text', visible: true, blackout: false, blink: false, secondarySource: null },
       external: 'external',
     });
   });
 
   it('should not affect other properties when patching', () => {
-    const initialMessage = {
+    const newState = messageService.patch({
       timer: { text: 'initial text', visible: true },
-    };
+    });
 
-    const newState = messageService.patch(initialMessage);
-
-    expect(newState).toEqual({
+    expect(newState).toMatchObject({
       timer: { text: 'initial text', visible: true, blackout: false, blink: false, secondarySource: null },
       external: '',
     });
diff --git a/apps/server/src/stores/EventStore.ts b/apps/server/src/stores/EventStore.ts
index f60d62854..1405a23ba 100644
--- a/apps/server/src/stores/EventStore.ts
+++ b/apps/server/src/stores/EventStore.ts
@@ -3,6 +3,7 @@ import { RuntimeStore } from 'ontime-types';
 import { socket } from '../adapters/WebsocketAdapter.js';
 
 export type PublishFn = <T extends keyof RuntimeStore>(key: T, value: RuntimeStore[T]) => void;
+export type StoreGetter = <T extends keyof RuntimeStore>(key: T) => Partial<RuntimeStore>[T];
 
 let store: Partial<RuntimeStore> = {};