Merge pull request #6 from r-el/feature/advanced-create

feature/advanced create

Author: r-el

README.md

@@ -20,19 +20,24 @@ db.create({ name: 'John', age: 30 }, (err, result) => {
   console.log('Created:', result);
 });
 
-// Read
-db.read('id', (err, data) => {
-  console.log('Data:', data);
+// Read by ID
+db.findById(1, (err, item) => {
+  console.log('Item:', item);
+});
+
+// Read all
+db.readAll((err, items) => {
+  console.log('All items:', items);
 });
 
 // Update
-db.update('id', { age: 31 }, (err, result) => {
+db.update(1, { age: 31 }, (err, result) => {
   console.log('Updated:', result);
 });
 
 // Delete
-db.delete('id', (err) => {
-  console.log('Deleted');
+db.delete(1, (err, deletedItem) => {
+  console.log('Deleted:', deletedItem);
 });
 ```
 

lib/constants.js

@@ -0,0 +1,24 @@
+/**
+ * Constants and configuration for JsonFileCRUD
+ * @version 1.0.0
+ */
+
+export const OPERATION_TYPES = {
+  CREATE: 'create',
+  UPDATE: 'update',
+  DELETE: 'delete',
+  WRITE_ALL: 'writeAll'
+};
+
+export const ERROR_MESSAGES = {
+  ITEM_MUST_BE_OBJECT: 'Item must be an object',
+  DUPLICATE_ID: (idField, id) => `Item with ${idField} ${id} already exists`,
+  NOT_FOUND: (idField, id) => `Item with ${idField} ${id} not found`,
+  CANNOT_CHANGE_ID: (idField) => `Cannot change ${idField} field`,
+  FILE_PATH_REQUIRED: 'File path is required',
+  INVALID_JSON_ARRAY: 'File content is not a JSON array'
+};
+
+export const DEFAULT_CONFIG = {
+  ID_FIELD: 'id'
+};

lib/file-operations.js

@@ -0,0 +1,43 @@
+/**
+ * File operations utilities for JsonFileCRUD
+ * @version 1.0.0
+ */
+
+import fs from 'fs';
+import { ERROR_MESSAGES } from './constants.js';
+
+/**
+ * Read all items from a JSON file
+ * @param {string} filePath - Path to the JSON file
+ * @param {Function} callback - Called with (error, items)
+ */
+export function readAllFromFile(filePath, callback) {
+  fs.readFile(filePath, "utf-8", (err, content) => {
+    if (err && err.code !== "ENOENT") {
+      // File system error other than "file not found"
+      callback(err);
+    } else {
+      // File doesn't exist or read successfully - parse as JSON array
+      try {
+        const items = content ? JSON.parse(content) : [];
+        if (!Array.isArray(items)) {
+          throw new Error(ERROR_MESSAGES.INVALID_JSON_ARRAY);
+        }
+        callback(null, items);
+      } catch (error) {
+        callback(error);
+      }
+    }
+  });
+}
+
+/**
+ * Write items array to file
+ * @param {string} filePath - Path to the JSON file
+ * @param {Object[]} items - Array of items to write
+ * @param {Function} callback - Called with (error)
+ */
+export function writeItemsToFile(filePath, items, callback) {
+  const content = JSON.stringify(items, null, 2);
+  fs.writeFile(filePath, content, callback);
+}