1 files changed, 30 insertions, 23 deletions

diff --git a/packages/main/src/services/ConfigPersistenceService.ts b/packages/main/src/services/ConfigPersistenceService.ts
index 85b0088..61123d9 100644
--- a/packages/main/src/services/ConfigPersistenceService.ts
+++ b/packages/main/src/services/ConfigPersistenceService.ts
@@ -17,12 +17,10 @@
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-
-import { watch } from 'fs';
+import { FSWatcher, watch } from 'fs';
 import { readFile, stat, writeFile } from 'fs/promises';
 import JSON5 from 'json5';
 import { throttle } from 'lodash';
-import { IDisposer } from 'mobx-state-tree';
 import { join } from 'path';
 
 import type { ConfigSnapshotOut } from  '../stores/Config';
@@ -30,25 +28,26 @@ import type { ConfigSnapshotOut } from  '../stores/Config';
 export type ReadConfigResult = { found: true; data: unknown; } | { found: false; };
 
 export class ConfigPersistenceService {
-  readonly #userDataDir: string;
+  static inject = ['userDataDir', 'configFileName'] as const;
+
+  private readonly configFilePath: string;
 
-  readonly #configFileName: string;
+  private timeLastWritten: Date | null = null;
 
-  readonly #configFilePath: string;
+  private watcher: FSWatcher | null = null;
 
   constructor(
-    userDataDir: string,
-    configFileName: string,
+    private readonly userDataDir: string,
+    private readonly configFileName: string,
   ) {
-    this.#userDataDir = userDataDir;
-    this.#configFileName = configFileName;
-    this.#configFilePath = join(this.#userDataDir, this.#configFileName);
+    this.configFileName = configFileName;
+    this.configFilePath = join(this.userDataDir, this.configFileName);
   }
 
   async readConfig(): Promise<ReadConfigResult> {
     let configStr;
     try {
-      configStr = await readFile(this.#configFilePath, 'utf8');
+      configStr = await readFile(this.configFilePath, 'utf8');
     } catch (err) {
       if ((err as NodeJS.ErrnoException).code === 'ENOENT') {
         return { found: false };
@@ -61,20 +60,24 @@ export class ConfigPersistenceService {
     };
   }
 
-  async writeConfig(configSnapshot: ConfigSnapshotOut): Promise<Date> {
+  async writeConfig(configSnapshot: ConfigSnapshotOut): Promise<void> {
     const configJson = JSON5.stringify(configSnapshot, {
       space: 2,
     });
-    await writeFile(this.#configFilePath, configJson, 'utf8');
-    const { mtime } = await stat(this.#configFilePath);
-    return mtime;
+    await writeFile(this.configFilePath, configJson, 'utf8');
+    const stats = await stat(this.configFilePath);
+    this.timeLastWritten = stats.mtime;
   }
 
-  watchConfig(callback: (mtime: Date) => Promise<void>, throttleMs: number): IDisposer {
+  watchConfig(callback: () => Promise<void>, throttleMs: number): void {
+    if (this.watcher !== null) {
+      throw new Error('watchConfig was already called');
+    }
+
     const configChanged = throttle(async () => {
       let mtime: Date;
       try {
-        const stats = await stat(this.#configFilePath);
+        const stats = await stat(this.configFilePath);
         mtime = stats.mtime;
       } catch (err) {
         if ((err as NodeJS.ErrnoException).code === 'ENOENT') {
@@ -82,22 +85,26 @@ export class ConfigPersistenceService {
         }
         throw err;
       }
-      return callback(mtime);
+      if (this.timeLastWritten === null || mtime > this.timeLastWritten) {
+        return callback();
+      }
     }, throttleMs);
 
-    const watcher = watch(this.#userDataDir, {
+    this.watcher = watch(this.userDataDir, {
       persistent: false,
     });
 
-    watcher.on('change', (eventType, filename) => {
+    this.watcher.on('change', (eventType, filename) => {
       if (eventType === 'change'
-        && (filename === this.#configFileName || filename === null)) {
+        && (filename === this.configFileName || filename === null)) {
         configChanged()?.catch((err) => {
           console.log('Unhandled error while listening for config changes', err);
         });
       }
     });
+  }
 
-    return () => watcher.close();
+  dispose(): void {
+    this.watcher?.close();
   }
 }