[WIP] Consolidate Error Handling Utilities for Improved File and API Error Management

package.json

@@ -14,7 +14,8 @@
   },
   "devDependencies": {
     "@types/express": "^4.17.17",
+    "jest": "^30.0.3",
     "typescript": "^4.9.5",
     "vitest": "^0.34.6"
   }
-}
+}

src/fileErrorHandler.js

@@ -0,0 +1,62 @@
+const fs = require('fs/promises');
+
+/**
+ * Custom error class for file access and permission errors
+ */
+class FileAccessError extends Error {
+  constructor(message) {
+    super(message);
+    this.name = 'FileAccessError';
+  }
+}
+
+/**
+ * Middleware to handle file access and permission errors
+ * @param {Error} err - Error object
+ * @param {Object} req - Express request object
+ * @param {Object} res - Express response object
+ * @param {Function} next - Express next function
+ */
+const fileErrorHandler = (err, req, res, next) => {
+  // Log the error for internal tracking
+  console.error(`File Access Error: ${err.message}`);
+
+  // Handle specific file-related errors
+  if (err instanceof FileAccessError) {
+    return res.status(403).json({
+      error: 'File Access Denied',
+      message: 'Unable to access the requested file.'
+    });
+  }
+
+  // Fallback to generic server error
+  res.status(500).json({
+    error: 'Internal Server Error',
+    message: 'An unexpected error occurred while processing the file.'
+  });
+};
+
+/**
+ * Safely check file access and permissions
+ * @param {string} filePath - Path to the file to check
+ * @throws {FileAccessError} If file cannot be accessed
+ */
+const checkFileAccess = async (filePath) => {
+  try {
+    // Attempt to access file metadata
+    await fs.access(filePath);
+    await fs.stat(filePath);
+  } catch (error) {
+    // Translate system errors to custom FileAccessError
+    if (error instanceof Error) {
+      throw new FileAccessError(`Cannot access file: ${error.message}`);
+    }
+    throw new FileAccessError('Unknown file access error');
+  }
+};
+
+module.exports = {
+  FileAccessError,
+  fileErrorHandler,
+  checkFileAccess
+};

src/utils/error-response.js

@@ -36,7 +36,7 @@ const ERROR_TYPES = {
  * @param {Object} [additionalDetails] - Optional additional error details
  * @returns {Object} HTTP response with error details
  */
-export function createErrorResponse(res, type, customMessage, additionalDetails = {}) {
+function createErrorResponse(res, type, customMessage, additionalDetails = {}) {
   // Validate input
   if (!ERROR_TYPES[type]) {
     type = 'INTERNAL_SERVER_ERROR';
@@ -61,7 +61,7 @@ export function createErrorResponse(res, type, customMessage, additionalDetails
  * @param {Object} [context] - Additional context for logging
  * @returns {Object} Structured error object
  */
-export function createErrorLog(type, message, context = {}) {
+function createErrorLog(type, message, context = {}) {
   return {
     timestamp: new Date().toISOString(),
     type,
@@ -70,7 +70,7 @@ export function createErrorLog(type, message, context = {}) {
   };
 }
 
-export default {
+module.exports = {
   createErrorResponse,
   createErrorLog,
   ERROR_TYPES

test/error-response.test.js

@@ -1,11 +1,10 @@
-import { describe, it, expect, vi } from 'vitest';
-import { createErrorResponse, createErrorLog } from '../src/utils/error-response.js';
+const { createErrorResponse, createErrorLog } = require('../src/utils/error-response.js');
 
 describe('Error Response Utility', () => {
   // Mock Express response object
   const createMockResponse = () => ({
-    status: vi.fn().mockReturnThis(),
-    json: vi.fn().mockReturnThis()
+    status: jest.fn().mockReturnThis(),
+    json: jest.fn().mockReturnThis()
   });
 
   describe('createErrorResponse', () => {

test/fileErrorHandler.test.js

@@ -0,0 +1,30 @@
+const fs = require('fs/promises');
+const { checkFileAccess, FileAccessError } = require('../src/fileErrorHandler');
+
+describe('File Error Handling', () => {
+  beforeEach(() => {
+    jest.restoreAllMocks();
+  });
+
+  it('should throw FileAccessError when file cannot be accessed', async () => {
+    // Mock fs.access to simulate permission denied
+    jest.spyOn(fs, 'access').mockRejectedValue(new Error('Permission denied'));
+
+    await expect(checkFileAccess('/path/to/nonexistent/file')).rejects.toThrow(FileAccessError);
+  });
+
+  it('should successfully check file access when file exists', async () => {
+    // Create mock for successful file access
+    jest.spyOn(fs, 'access').mockResolvedValue();
+    jest.spyOn(fs, 'stat').mockResolvedValue({});
+
+    await expect(checkFileAccess('/path/to/valid/file')).resolves.not.toThrow();
+  });
+
+  it('should handle unknown errors during file access', async () => {
+    // Simulate an unknown error
+    jest.spyOn(fs, 'access').mockRejectedValue(new Error());
+
+    await expect(checkFileAccess('/path/to/file')).rejects.toThrow(FileAccessError);
+  });
+});

tests/fileErrorHandler.test.ts

@@ -1,27 +0,0 @@
-import { describe, it, expect, vi } from 'vitest';
-import fs from 'fs/promises';
-import { checkFileAccess, FileAccessError } from '../src/fileErrorHandler';
-
-describe('File Error Handling', () => {
-  it('should throw FileAccessError when file cannot be accessed', async () => {
-    // Mock fs.access to simulate permission denied
-    vi.spyOn(fs, 'access').mockRejectedValue(new Error('Permission denied'));
-
-    await expect(checkFileAccess('/path/to/nonexistent/file')).rejects.toThrow(FileAccessError);
-  });
-
-  it('should successfully check file access when file exists', async () => {
-    // Create mock for successful file access
-    vi.spyOn(fs, 'access').mockResolvedValue(undefined);
-    vi.spyOn(fs, 'stat').mockResolvedValue({} as any);
-
-    await expect(checkFileAccess('/path/to/valid/file')).resolves.not.toThrow();
-  });
-
-  it('should handle unknown errors during file access', async () => {
-    // Simulate an unknown error
-    vi.spyOn(fs, 'access').mockRejectedValue(new Error());
-
-    await expect(checkFileAccess('/path/to/file')).rejects.toThrow(FileAccessError);
-  });
-});