Check if the file has changed using the file hash instead of fetching the entire file first

.github/workflows/ci-cd.yml

@@ -3,10 +3,7 @@ name: CI/CD Pipeline
 on:
   push:
     branches:
-      - production-release
-  pull_request:
-    branches:
-      - production-release
+      - main
 
 jobs:
   build:

package.json

@@ -3,7 +3,7 @@
   "displayName": "Prompt Vault extension",
   "description": "Sync GitHub Copilot prompts, chatmodes and instructions from git repositories",
   "version": "1.2.0",
-  "publisher": "logient-nventive",
+  "publisher": "logientnventive",
   "repository": {
     "type": "git",
     "url": "https://github.com/nventive/PromptVault.git",

src/syncManager.ts

@@ -171,40 +171,46 @@ export class SyncManager {
         await this.fileSystem.ensureDirectoryExists(promptsDir);
 
         let itemsUpdated = 0;
+        let statusBarRepoCount = 0;
 
         for (const file of files) {
             this.logger.debug(`Syncing file: ${file.path}`);
+            this.statusBar.setStatus(SyncStatus.Syncing, `Syncing ${statusBarRepoCount}/${files.length}`);
+            statusBarRepoCount++;
+
             let content = null;
+            const fileName = this.fileSystem.getBasename(file.path);
+            const localPath = this.fileSystem.joinPath(promptsDir, fileName);
 
             try {
+                const fileExists = await this.fileSystem.fileExists(localPath);
+                if(fileExists) {
+                    const localFileContent = await this.fileSystem.readFileContent(localPath);
+                    const localFileHash = await this.fileSystem.calculateFileHash(localFileContent);
+
+                    const githubFileHash = await this.github.getFileHash(owner, repo, file.path, this.config.branch);
+                    if(localFileHash === githubFileHash) {
+                        this.logger.info(`File ${file.path} is up to date, skipping`);
+                        continue; 
+                    }
+                }
+
                 content = await this.github.getFileContent(owner, repo, file.path, this.config.branch);
             } catch (error) {
                 // An error occured will retrieving file content, Return here
                 this.logger.warn(`Failed to fetch content for ${file.path}: ${error}`);
-                this.notifications.showSyncError(`Failed to fetch content for ${file.path}: ${error}. Make sure that the correct is set. Current branch: ${this.config.branch}`);
+                this.notifications.showSyncError(`Failed to fetch content for ${file.path}: ${error}. Make sure that the branch is correct. Current branch: ${this.config.branch}`);
                 return itemsUpdated;
             }
 
             try {
-                // Flatten the structure - extract just the filename and place directly in prompts directory
-                const fileName = this.fileSystem.getBasename(file.path);
-                const localPath = this.fileSystem.joinPath(promptsDir, fileName);
-
-                // Check if file needs updating
                 if(!content) {
                     this.logger.warn(`No content retrieved for ${file.path}, skipping`);
                     continue;
                 }
-                const needsUpdate = await this.shouldUpdateFile(localPath, content);
-
-                if (needsUpdate) {
-                    await this.fileSystem.writeFileContent(localPath, content);
-                    itemsUpdated++;
-                    this.logger.debug(`Updated file: ${localPath}`);
-                } else {
-                    this.logger.debug(`File unchanged: ${localPath}`);
-                }
-
+
+                await this.fileSystem.writeFileContent(localPath, content);
+                itemsUpdated++;
             } catch (error) {
                 this.logger.warn(`Failed to sync file ${file.path}: ${error}`);
                 // Continue with other files even if one fails
@@ -285,19 +291,6 @@ export class SyncManager {
         };
     }
 
-    private async shouldUpdateFile(localPath: string, newContent: string): Promise<boolean> {
-        try {
-            if (!(await this.fileSystem.fileExists(localPath))) {
-                return true; // File doesn't exist, needs to be created
-            }
-
-            const existingContent = await this.fileSystem.readFileContent(localPath);
-            return existingContent !== newContent;
-        } catch {
-            return true; // Error reading file, assume it needs updating
-        }
-    }
-
     private scheduleNextSync(): void {
         // Clear existing timer
         if (this.timer) {

src/utils/fileSystem.ts

@@ -61,6 +61,21 @@ export class FileSystemManager {
     async copyFile(source: string, destination: string): Promise<void> {
         const content = await this.readFileContent(source);
         await this.writeFileContent(destination, content);
+    }   
+
+    async calculateFileHash(content: string): Promise<string> {
+        // GitHub uses the following format: `blob ${content.length}\0${content}`
+        const blobPrefix = `blob ${Buffer.from(content).length}\0`;
+        const fullContent = blobPrefix + content;
+
+        const encoder = new TextEncoder();
+        const data = encoder.encode(fullContent);
+        const hashBuffer = await crypto.subtle.digest('SHA-1', data);
+
+        const hashArray = Array.from(new Uint8Array(hashBuffer));
+        const hashHex = hashArray.map(b => b.toString(16).padStart(2, '0')).join('');
+
+        return hashHex;
     }
 
     getRelativePath(from: string, to: string): string {

src/utils/github.ts

@@ -111,6 +111,28 @@ export class GitHubApiManager {
         throw new Error('No content found in file');
     }
 
+    async getFileHash(owner: string, repo: string, path: string, branch: string = 'master'): Promise<string> {
+        const session = await vscode.authentication.getSession('github', ['repo'], { createIfNone: false });
+        if (!session) {
+            throw new Error('GitHub authentication required');
+        }
+
+        const response = await fetch(`${this.baseUrl}/repos/${owner}/${repo}/contents/${path}?ref=${branch}`, {
+            headers: {
+                'Authorization': `Bearer ${session.accessToken}`,
+                'Accept': 'application/vnd.github.v3+json',
+                'User-Agent': 'VS Code Prompts Sync Extension'
+            }
+        });
+
+        if (!response.ok) {
+            throw new Error(`Failed to get file hash: ${response.status} ${response.statusText}`);
+        }
+
+        const data = await response.json();
+        return data.sha;
+    }
+
     parseRepositoryUrl(url: string): { owner: string; repo: string } {
         // Handle different GitHub URL formats
         const patterns = [