Build LocalStorage persistence (js/storage.js)

Goal

Ensure all profiles (added, edited, or deleted) are saved automatically and loaded again when the page reloads — no data loss.

File Ownership

You fully own:
/js/storage.js
Only you touch this file. You create all functions related to saving and loading profiles.

Learning Concepts

JSON.stringify() and JSON.parse()

Browser localStorage API

Exporting and importing JS functions

Code modularization and function reusability

Functional Requirements
1. Create saveProfiles(profilesArray)

This function receives the current list of profiles (an array of objects) and saves it to localStorage.

function saveProfiles(profilesArray) {
localStorage.setItem("profiles", JSON.stringify(profilesArray));
}

Every time a profile is added, edited, or deleted — other modules will call this function to update storage.

2. Create loadProfiles()

This function loads the saved profiles from localStorage when the app starts.

Steps:

Get the stored item:

const storedData = localStorage.getItem("profiles");

If data exists, parse and return it:

if (storedData) {
return JSON.parse(storedData);
}

Otherwise, return an empty array:

return [];

Final version:

function loadProfiles() {
const storedData = localStorage.getItem("profiles");
return storedData ? JSON.parse(storedData) : [];
}

3. Export Both Functions
export { saveProfiles, loadProfiles };

4. Integration Example

In app.js or profiles.js, teammates will call your functions like this:

When App Starts

import { loadProfiles } from "./storage.js";

let profiles = loadProfiles();

When Profiles Are Updated

import { saveProfiles } from "./storage.js";

saveProfiles(profiles);

Definition of Done

Profiles persist even after page reload.

saveProfiles() and loadProfiles() work without breaking anything.

No duplication or undefined data.

No console errors.

Code is modular, clear, and fully commented.

(Optional)

Add a timestamp when saving (e.g., lastSaved: new Date()).

Log in console when saving/loading occurs for debugging.

The work is isolated to /js/storage.js. Start by creating the file and implementing the saveProfiles and loadProfiles functions as described. Test by integrating them into app.js or profiles.js to ensure profiles persist across page reloads. Check for console errors and verify data is saved and loaded correctly using the browser's developer tools.

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