feat: extension file reload — watch for plugin changes and hot-reload runtime

packages/cli/src/config/extension-file-watcher.ts

@@ -0,0 +1,304 @@
+/**
+ * @license
+ * Copyright 2025 Qwen
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import * as fs from 'node:fs';
+import * as path from 'node:path';
+import { watch as watchFs, type FSWatcher } from 'chokidar';
+import {
+  createDebugLogger,
+  isSubpath,
+  Storage,
+  type Config,
+  type ExtensionMutationEvent,
+} from '@qwen-code/qwen-code-core';
+import { ExtensionRefreshState } from './extension-refresh-state.js';
+
+const debugLogger = createDebugLogger('EXTENSION_FILE_WATCHER');
+
+const TOP_LEVEL_FILES = new Set([
+  'extension-enablement.json',
+  'extension-preferences.json',
+  'marketplaces.json',
+]);
+
+const EXTENSION_FILES = new Set([
+  'qwen-extension.json',
+  '.qwen-extension-install.json',
+]);
+
+const AUTO_REFRESH_DIRS = new Set(['commands', 'skills', 'agents']);
+const STALE_DIRS = new Set(['hooks']);
+
+type WatchEvent = 'add' | 'addDir' | 'change' | 'unlink' | 'unlinkDir';
+type RefreshAction = 'auto' | 'stale';
+
+export class ExtensionFileWatcher {
+  private watcher?: FSWatcher;
+  private bootstrapWatcher?: FSWatcher;
+  private mutationListenerDisposer?: () => void;
+  private mutationSuppressionEnds = new Map<number, () => void>();
+  private contextFiles = new Set<string>();
+  private watching = false;
+  private watchGeneration = 0;
+
+  constructor(
+    private readonly config: Config,
+    private readonly extensionsDir = Storage.getUserExtensionsDir(),
+    private readonly refreshState = new ExtensionRefreshState(),
+  ) {}
+
+  startWatching(): void {
+    this.stopWatching();
+    this.watching = true;
+    const generation = ++this.watchGeneration;
+    this.subscribeExtensionManagerMutations();
+    this.contextFiles = this.getContextFiles();
+    const roots = this.getWatchRoots();
+
+    if (roots.length > 0) {
+      this.watcher = watchFs(roots, {
+        ignoreInitial: true,
+        followSymlinks: false,
+        awaitWriteFinish: {
+          stabilityThreshold: 200,
+          pollInterval: 50,
+        },
+        ignored: (filePath: string) => this.isIgnored(filePath),
+      })
+        .on('all', (event: string, changedPath: string) => {
+          if (generation !== this.watchGeneration) return;
+          const action = this.getRefreshAction(
+            event as WatchEvent,
+            path.resolve(changedPath),
+          );
+          if (action === 'auto') {
+            this.refreshState.markExtensionContentChanged(
+              'extension content files changed',
+            );
+          } else if (action === 'stale') {
+            this.refreshState.markExtensionsChanged('extension files changed');
+          }
+        })
+        .on('error', (error: unknown) => {
+          debugLogger.warn('Extension file watcher error:', error);
+        });
+    }
+
+    if (!fs.existsSync(this.extensionsDir)) {
+      this.watchExtensionsParent();
+    }
+  }
+
+  stopWatching(): void {
+    const watcher = this.watcher;
+    const bootstrapWatcher = this.bootstrapWatcher;
+    this.watcher = undefined;
+    this.bootstrapWatcher = undefined;
+    this.watching = false;
+    this.watchGeneration++;
+    this.mutationListenerDisposer?.();
+    this.mutationListenerDisposer = undefined;
+    this.endPendingMutationSuppressions();
+    watcher?.close().catch((error: unknown) => {
+      debugLogger.warn('Extension file watcher close error:', error);
+    });
+    bootstrapWatcher?.close().catch((error: unknown) => {
+      debugLogger.warn('Extension bootstrap watcher close error:', error);
+    });
+  }
+
+  restartWatching(): void {
+    this.startWatching();
+  }
+
+  private getWatchRoots(): string[] {
+    const roots = new Set<string>();
+    if (fs.existsSync(this.extensionsDir)) {
+      roots.add(this.extensionsDir);
+    }
+    for (const extension of this.config.getExtensions()) {
+      if (extension.installMetadata?.type === 'link') {
+        const rawSource = extension.installMetadata.source;
+        const source = rawSource ? path.resolve(rawSource) : undefined;
+        if (source && fs.existsSync(source)) {
+          roots.add(source);
+        }
+      }
+    }
+    return [...roots];
+  }
+
+  private getContextFiles(): Set<string> {
+    const files = new Set<string>();
+    for (const extension of this.config.getExtensions()) {
+      for (const filePath of extension.contextFiles) {
+        files.add(path.resolve(filePath));
+      }
+      const configured = extension.config.contextFileName;
+      const names =
+        configured === undefined
+          ? ['QWEN.md']
+          : Array.isArray(configured)
+            ? configured
+            : [configured];
+      for (const name of names) {
+        files.add(path.resolve(extension.path, name));
+      }
+    }
+    return files;
+  }
+
+  private watchExtensionsParent(): void {
+    const parentDir = path.dirname(this.extensionsDir);
+    const dirBasename = path.basename(this.extensionsDir);
+    const generation = this.watchGeneration;
+    this.bootstrapWatcher = watchFs(parentDir, {
+      ignoreInitial: true,
+      followSymlinks: false,
+      depth: 0,
+      ignored: (filePath: string) =>
+        filePath !== parentDir && path.basename(filePath) !== dirBasename,
+    })
+      .on('all', (_event: string, changedPath: string) => {
+        if (generation !== this.watchGeneration) return;
+        if (path.basename(changedPath) !== dirBasename) return;
+        if (!fs.existsSync(this.extensionsDir)) return;
+        this.refreshState.markExtensionsChanged('extension directory created');
+        queueMicrotask(() => {
+          if (this.watching) {
+            this.restartWatching();
+          }
+        });
+      })
+      .on('error', (error: unknown) => {
+        debugLogger.warn('Extension bootstrap watcher error:', error);
+      });
+  }
+
+  private getRefreshAction(
+    event: WatchEvent,
+    changedPath: string,
+  ): RefreshAction | false {
+    if (this.contextFiles.has(changedPath)) {
+      return 'stale';
+    }
+    if (changedPath === path.resolve(this.extensionsDir)) {
+      if (event === 'unlinkDir') {
+        this.watchExtensionsParent();
+        return 'stale';
+      }
+      return false;
+    }
+    if (isSubpath(this.extensionsDir, changedPath)) {
+      return this.getUserExtensionRefreshAction(event, changedPath);
+    }
+    return this.getLinkedExtensionRefreshAction(changedPath);
+  }
+
+  private getUserExtensionRefreshAction(
+    event: WatchEvent,
+    changedPath: string,
+  ): RefreshAction | false {
+    const relative = path.relative(this.extensionsDir, changedPath);
+    const parts = relative.split(path.sep).filter(Boolean);
+    if (parts.length === 1) {
+      if (TOP_LEVEL_FILES.has(parts[0])) return 'stale';
+      if (event === 'addDir' || event === 'unlinkDir') return 'stale';
+      return false;
+    }
+    if (
+      !fs.existsSync(
+        path.join(this.extensionsDir, parts[0], 'qwen-extension.json'),
+      )
+    ) {
+      return 'stale';
+    }
+    const runtimePath = parts.slice(1);
+    return this.getRuntimePathRefreshAction(runtimePath);
+  }
+
+  private getLinkedExtensionRefreshAction(
+    changedPath: string,
+  ): RefreshAction | false {
+    for (const extension of this.config.getExtensions()) {
+      if (extension.installMetadata?.type !== 'link') continue;
+      const rawSource = extension.installMetadata.source;
+      const source = rawSource ? path.resolve(rawSource) : undefined;
+      if (!source || !isSubpath(source, changedPath)) continue;
+      const relative = path.relative(source, changedPath);
+      const parts = relative.split(path.sep).filter(Boolean);
+      return parts.length === 0
+        ? 'stale'
+        : this.getRuntimePathRefreshAction(parts);
+    }
+    return false;
+  }
+
+  private getRuntimePathRefreshAction(parts: string[]): RefreshAction | false {
+    if (EXTENSION_FILES.has(parts[0]) || STALE_DIRS.has(parts[0])) {
+      return 'stale';
+    }
+    if (AUTO_REFRESH_DIRS.has(parts[0])) {
+      return 'auto';
+    }
+    return false;
+  }
+
+  private isIgnored(filePath: string): boolean {
+    const normalized = filePath.replace(/\\/g, '/');
+    const searchablePath = `/${normalized}/`;
+    if (
+      searchablePath.includes('/node_modules/') ||
+      searchablePath.includes('/.git/')
+    ) {
+      return true;
+    }
+    const basename = normalized.split('/').pop() ?? '';
+    return (
+      basename === '.DS_Store' ||
+      basename.endsWith('~') ||
+      basename.endsWith('.swp') ||
+      basename.endsWith('.tmp')
+    );
+  }
+
+  private subscribeExtensionManagerMutations(): void {
+    const manager = this.config.getExtensionManager();
+    this.mutationListenerDisposer = manager.addMutationListener(
+      (event: ExtensionMutationEvent) => {
+        if (event.phase === 'start') {
+          this.mutationSuppressionEnds.set(
+            event.id,
+            this.refreshState.beginSuppression(() =>
+              this.restartAfterMutation(),
+            ),
+          );
+          return;
+        }
+        const endSuppression = this.mutationSuppressionEnds.get(event.id);
+        if (!endSuppression) {
+          return;
+        }
+        this.mutationSuppressionEnds.delete(event.id);
+        endSuppression();
+      },
+    );
+  }
+
+  private endPendingMutationSuppressions(): void {
+    const endSuppressions = [...this.mutationSuppressionEnds.values()];
+    this.mutationSuppressionEnds.clear();
+    for (const endSuppression of endSuppressions) {
+      endSuppression();
+    }
+  }
+
+  private restartAfterMutation(): void {
+    if (this.watching) {
+      this.restartWatching();
+    }
+  }
+}