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How can I make the data inside of my Cart become persistent?

I have a NextJS application that is using the ShopifyBuy SDK. I have been successfully able to implement a solution where I am able to fetch the products from Store and display them to the User. The user is also able to go to a product page and add the product to the cart.
However, when the user refreshes the page, the cart is reset, and the data does not persist. The code is below:
context/cart.js:
import { createContext, useContext, useEffect, useReducer } from "react";
import client from "../lib/client";
import Cookies from "js-cookie";
const CartStateContext = createContext();
const CartDispatchContext = createContext();
const SET_CART = "SET_CART";
const initalState = {
lineItems: [],
totalPrice: 0,
webUrl: "",
id: "",
};
const reducer = (state, action) => {
switch (action.type) {
case SET_CART:
return { ...state, ...action.payload };
default:
throw new Error(`Unknown action: ${action.type}`);
}
};
export const CartProvider = ({ children }) => {
const savedState = Cookies.get("cartState");
const [state, dispatch] = useReducer(reducer, savedState || initalState);
useEffect(() => {
Cookies.set("cartState", state, { expires: 7 });
}, [state]);
useEffect(() => {
getCart();
}, []);
const setCart = (payload) => dispatch({ type: SET_CART, payload });
const getCart = async () => {
try {
const cart = await client.checkout.create();
setCart(cart);
} catch (err) {
console.log(err);
}
};
return (
<CartDispatchContext.Provider value={{ setCart }}>
<CartStateContext.Provider value={{ state }}>
{children}
</CartStateContext.Provider>
</CartDispatchContext.Provider>
);
};
export const useCartState = () => useContext(CartStateContext);
export const useCartDispatch = () => useContext(CartDispatchContext);
products/[handle].tsx:
import React, { useState, useEffect } from "react";
import client from "../../lib/client";
import { useCartDispatch, useCartState } from "../../context/cart";
import Link from "next/link";
import cookie from "js-cookie";
export const getStaticPaths = async () => {
const res = await client.product.fetchAll();
const paths = res.map((product: any) => {
return {
params: { handle: product.handle.toString() },
};
});
return {
paths,
fallback: false,
};
};
export const getStaticProps = async (context: any) => {
const handle = context.params.handle;
const res = await client.product.fetchByHandle(handle);
const product = JSON.stringify(res);
return {
props: {
product,
},
};
};
function Product({ product }: any) {
const { state } = useCartState();
const { setCart } = useCartDispatch();
const addToCart = async () => {
const checkoutId = state.id;
const lineItemsToAdd = [
{
variantId: product.variants[0].id,
quantity: 1,
},
];
const res = await client.checkout.addLineItems(checkoutId, lineItemsToAdd);
setCart(res);
};
product = JSON.parse(product);
return (
<div>
<div className=" flex-col text-2xl font-bold m-8 flex items-center justify-center ">
<h1>{product.title}</h1>
<button onClick={addToCart}>Add to Cart</button>
<Link href="/cart">Checkout</Link>
</div>
</div>
);
}
export default Product;
pages/cart/index.tsx:
import React, { useEffect } from "react";
import { useCartState, useCartDispatch } from "../../context/cart";
import client from "../../lib/client";
function Cart() {
const { state } = useCartState();
return (
<div>
<h1>Cart</h1>
{state.lineItems &&
state.lineItems.map((item: any) => {
return (
<div key={item.id}>
<h2>{item.title}</h2>
<p>{item.variant.title}</p>
<p>{item.quantity}</p>
</div>
);
})}
</div>
);
}
export default Cart;
I have tried using a library called js-cookie and also localStorage. I'm not sure where the problem lies or if the solutions that I've tried are wrong.
P.S.: I'm fairly new to NextJS and Typescript so go easy on the syntax. This code is for a personal project. Thanks in advance!

Answering this because I ended up coming up with a solution that works for me, at least.
Here it is:
const getCart = async () => {
try {
const checkoutId = Cookies.get("checkoutId");
let cart;
if (checkoutId) {
cart = await client.checkout.fetch(checkoutId);
} else {
cart = await client.checkout.create();
Cookies.set("checkoutId", cart.id);
}
setCart(cart);
} catch (err) {
console.log(err);
}
};
From my understanding, what this does is the following:
Check the cookies to see if one exists called "checkoutId"
If it exists, fetch the cart using that checkoutId
Otherwise, create a new cart and create a cookie using the cart.id that is returned in the response
Then, inside my individual Product page ([handle].tsx), I'm doing the following:
const addToCart = async () => {
const checkoutId = state.id;
const lineItemsToAdd = [
{
variantId: product.variants[0].id,
quantity: 1,
},
];
const res = await client.checkout.addLineItems(checkoutId, lineItemsToAdd);
console.log(res);
if (cookie.get("checkoutId") === undefined) {
cookie.set("checkoutId", res.id);
}
setCart(res);
};

Using cookies to store your object cart, as far as I know, is not a good idea. You could use localStorage, like so:
import { createContext, useContext, useEffect, useReducer } from "react";
import client from "../lib/client";
const CartStateContext = createContext();
const CartDispatchContext = createContext();
const SET_CART = "SET_CART";
const initalState =
typeof localStorage !== "undefined" && localStorage.getItem("cartState")
? JSON.parse(localStorage.getItem("cartState"))
: {
lineItems: [],
totalPrice: 0,
webUrl: "",
id: "",
};
const reducer = (state, action) => {
switch (action.type) {
case SET_CART:
return { ...state, ...action.payload };
default:
throw new Error(`Unknown action: ${action.type}`);
}
};
export const CartProvider = ({ children }) => {
const [state, dispatch] = useReducer(reducer, initalState);
useEffect(() => {
localStorage.set("cartState", JSON.stringify(state));
}, [state]);
useEffect(() => {
getCart();
}, []);
const setCart = (payload) => dispatch({ type: SET_CART, payload });
const getCart = async () => {
try {
const cart = await client.checkout.create();
setCart(cart);
} catch (err) {
console.log(err);
}
};
return (
<CartDispatchContext.Provider value={{ setCart }}>
<CartStateContext.Provider value={{ state }}>{children}</CartStateContext.Provider>
</CartDispatchContext.Provider>
);
};
export const useCartState = () => useContext(CartStateContext);
export const useCartDispatch = () => useContext(CartDispatchContext);

Items array can't be loaded

DonationList.js
import React, { useEffect, useState } from "react";
import { getDocs, collection } from "firebase/firestore";
import { auth, db } from "../firebase-config";
import Donation from "./Donation";
const DonationList = () => {
const [donations, setDonations] = useState([]);
//loadDonations
const loadDonations = async () => {
const donationsCollectionRef = collection(db, "donations");
const querySnapshot = await getDocs(donationsCollectionRef);
querySnapshot.forEach(async (donationSnap) => {
const items = [];
const itemsCollectionRef = collection(db, "donations", donationSnap.id, "items");
const itemquerySnapshot = await getDocs(itemsCollectionRef);
itemquerySnapshot.forEach((itemSnap) => {
items.push([
{
itemType: itemSnap.data().itemType,
quantity: itemSnap.data().quantity,
},
]);
});
setDonations((prevDonation) => {
return [
...prevDonation,
{
type: donationSnap.data().type,
donor: donationSnap.data().donor,
requestor: donationSnap.data().requestor,
items: items,
},
];
});
items = [];
});
};
useEffect(() => {
loadDonations();
}, []);
return (
<div className="grid">
<div className="col-12">
<div className="card">
<h5>Donation List</h5>
{donations.map((donation) => (
<Donation donation={donation} />
))}
</div>
</div>
</div>
);
};
const comparisonFn = function (prevProps, nextProps) {
return prevProps.location.pathname === nextProps.location.pathname;
};
export default React.memo(DonationList, comparisonFn);
Donation.js
import React, { useState } from "react";
const Donation = (props) => {
return (
<div className="card">
<h5>Donation Type</h5>
{props.donation.type}
<h5>Requestor</h5>
{props.donation.requestor}
<h5>Donor</h5>
{props.donation.donor}
<h5>Items</h5>
{props.donation.items.map((item) => (
<Item item={item} />
))}
</div>
);
};
const Item = (props) => {
console.log(props.item)
return (
<React.Fragment>
ItemType: {props.item.itemType}
Quantity: {props.item.quantity}
</React.Fragment>
);
};
export default Donation;
These two code snippets is me trying to take data from firebase and display it.
When I console.log(props.item) in the Item component function, the item seems to be an array.
screenshot of the log
Shouldn't it be an object like props.donation?
Its my first time using reactJS so I can't seem to find the problem

Check this block in your code.
const items = [];
itemquerySnapshot.forEach((itemSnap) => {
items.push([
{
itemType: itemSnap.data().itemType,
quantity: itemSnap.data().quantity,
},
]);
});
You have already defined an array and added the item as an array. That is why you are accessing item in Donations; it's returning as an array type.
{props.donation.items.map((item) => (
<Item item={item} />
))}
Change your loadDonations method like this, and it will work correctly.
itemquerySnapshot.forEach((itemSnap) => {
items.push(
{
itemType: itemSnap.data().itemType,
quantity: itemSnap.data().quantity,
},
);
})

Displaying response from API in react component

I'm trying to display the response from the API into my react component but it's not working. If I try to use it in the console, I can see the data and its value but not in the react component, it's empty when I try to show the value in a div.
Here is the code where I'm trying to display it in my react component:
const CharacterListing = () => {
const characters = useSelector(getAllCharacters);
console.log("Hello", characters);
const renderCharacters = Object.entries(characters).map(([key, value]) => {
console.log(value.name);
<div>{value.name}</div>
})
return (
<div>
{renderCharacters}
</div>
);
};
export default CharacterListing;
This is the code for my Character Slice Component
const initialState = {
characters: {},
};
const characterSlice = createSlice({
name: 'characters',
initialState,
reducers: {
addCharacters: (state, { payload }) => {
state.characters = payload;
},
},
});
export const { addCharacters } = characterSlice.actions;
export const getAllCharacters = (state) => state.characters.characters;
export default characterSlice.reducer;
This is the code for my Home Component:
const Home = () => {
const dispatch = useDispatch();
useEffect(() => {
const fetchCharacters = async () => {
const response = await baseURL.get(`/characters`)
.catch(error => {
console.log("Error", error);
});
dispatch(addCharacters(response.data));
console.log("Success", response);
};
fetchCharacters();
}, [])
return (
<div>
Home
<CharacterListing />
</div>
);
};
export default Home;
Thank you

You forgot to return item into your map func
Try this :
const renderCharacters = Object.entries(characters).map(([key, value]) => {
console.log(value.name);
return <div key={key}>{value.name}</div>
})

How to prevent my Page render when I click on the button

I am trying to optimize my react application, while profiling my application I found that when I click on Add to cart page my whole page is getting re-rendered. Could anyone help me with, how to avoid that and why it is happening?
FYR, GitHub repo:https://github.com/sandeep8080/shopping-cart-assignment
import { useCallback, useEffect, useState } from "react";
import { useDispatch, useSelector } from "react-redux";
import SideBar from "../../components/sideBar/SideBar";
import { getProductsData } from "../../redux/action/products";
import ProductCard from '../../components/productCard/ProductCard';
import './products.css';
import { getCategoryData } from "../../redux/action/category";
import Cart from "../cart/cart";
import Modal from '../../components/modal/Modal';
import { useHistory, useParams } from "react-router";
const ProductsPage = () => {
const dispatch = useDispatch();
const router = useHistory();
const { id } = useParams();
console.log(` product comp : ${id}`);
const productsData = useSelector(data => data.Products.products);
const sideBarData = useSelector(data => {
const listItems = data.Categories.CategoriesItems;
const activeListItems = listItems.filter(item => item.enabled === true);
return activeListItems;
});
const openCart = useSelector(state => state.CartDetails.isOpen);
const [fProductData, setFProductData] = useState([]);
useEffect(() => {
dispatch(getProductsData());
dispatch(getCategoryData());
}, []);
useEffect(() => {
if (id) {
filterDataByCategory(id);
} else {
setFProductData(productsData);
}
}, [productsData, id]);
// Function to filter out the data based on category
const filterDataByCategory = (id) => {
console.log("Filter data function called")
const filterData = productsData.filter(item => item.category === id);
setFProductData(filterData);
};
const handleClickProduct = useCallback((id) => {
filterDataByCategory(id);
router.push(`/products/${id}`);
}, [id]);
return (
<div className='product-main'>
<SideBar
sideBarData={sideBarData}
handleClickProduct={handleClickProduct}
/>
<div className='product-container'>
<div className='product-row'>
{
(fProductData).map((product) => {
return (
<div key={product.id} className='card-wrapper' >
<ProductCard key={product.id} {...product} />
</div>
)
})
}
</div>
</div>
{
openCart &&
<Modal>
<Cart />
</Modal>
}
</div >
)
};
export default ProductsPage;
// Product Card component
import './ProductCard.css';
import Button from '../button/Button';
import React from 'react';
import { useDispatch } from 'react-redux';
import { updateCart } from '../../redux/action/cart';
import priceFromatter from '../../lib/priceFromatter';
const ProductCard = ({ name, price, description, imageURL, id }) => {
const dispatch = useDispatch();
const handleClick = () => {
console.log('product clicked', id);
dispatch(updateCart(id, 'add'));
};
let imgURL = `../../${imageURL}`;
// imgURL = imgURL.replace(/([^:]\/)\/+/g, "$1");
// const image = React.lazy(() => import (`${imgURL}`));
// console.log(image);
return (
<article className='card-container'>
<h6 className='card-header'>
{name}
</h6>
<div className='content-container'>
<img
className='content-img'
// src={require(`${imgURL}`).default}
src={imageURL}
/>
<div className='content'>
<p className='content-desc'>{description}</p>
<div className='content-footer'>
<p>{priceFromatter(price)}</p>
<Button btnText='Add To Cart' handleClick={() => handleClick(id)} />
</div>
</div>
</div>
</article>
)
};
export default ProductCard;
import { callApi } from "../../lib/api";
import { actions } from '../actionContants/actionConstant';
export const toggleCart = (isToggle) => {
return {
type: actions.OPEN_CART,
payload: isToggle,
}
};
export const updateCart = (id, operation) => {
return async (dispatch, getState) => {
const productList = getState().Products.products;
const cartItems = getState().CartDetails.cartItems;
const currItem = productList.find(({ id: currentItemId }) => currentItemId === id);
const isItemInCart = cartItems.find(({ id }) => id === currItem.id);
let finalItem = [];
if (!isItemInCart) {
finalItem = [...cartItems, { ...currItem, count: 1 }]
} else {
finalItem = cartItems.map(item => {
if (item.id === currItem.id) {
operation === 'add' ? item.count = item.count + 1 : item.count = item.count - 1
}
return item;
}).filter(({ count }) => count)
}
try {
const result = await callApi.post('/addToCart', id);
result && dispatch({
type: actions.UPDATE_TO_CART,
payload: finalItem
})
} catch (error) {
console.log(error)
}
}
};

In products.js change the following block of code:
const sideBarData = useSelector(data => {
const listItems = data.Categories.CategoriesItems;
const activeListItems = listItems.filter(item => item.enabled === true);
return activeListItems;
});
to:
const sideBarData = useSelector(data => {
const listItems = data.Categories.CategoriesItems;
const activeListItems = listItems.filter(item => item.enabled === true);
return activeListItems;
}, shallowEqual);
useSelector will force a component to re-render when the selector returns a new reference that is different than the previous reference (it uses the === operator). Ref: https://react-redux.js.org/api/hooks#equality-comparisons-and-updates. As you are filtering the array returned from the store, it will always be a different object reference to the one in the store.
The use of shallowEqual as the equalityFn to useSelector() can be used to change the comparison and prevent an unnecessary re-render of the <ProductsPage> component.

did you try using e.preventDefault() otherwise the answer above might work

React 'useContext' hook not re-rendering after context updates with database data

I am using React's Context API to share data that most of my components need.
The Context is initially defined, but shortly receives data from the Firebase database (please see IdeaContext.tsx). I define the context in a functional component and the display component, which returns a small card based on the information received.
However, the component doesn't render when I start the development server with Yarn. Instead, in order to get it to render, I have to write console.log('something') inside the display component and then it suddenly re-renders. However, when I refresh the server, it again doesn't render.
How can I make my component render immediately (or at least after the context updates with the data from the database?)
Code:
Context Definition:
import React, { createContext, useEffect, useState } from "react";
import { IdeaContextType, Idea } from "../t";
import {ideasRef} from './firebase'
function getIdeas() {
var arr: Array<Idea> = [];
ideasRef.on('value', (snapshot) => {
let items = snapshot.val()
snapshot.forEach( (idea) => {
const obj = idea.val()
arr.push({
title: obj.title,
description: obj.description,
keyID: obj.keyID
})
console.log(arr)
})
})
return arr
}
const IdeaContextDefaultValues: IdeaContextType = {
ideas: [],
setIdeas: () => {},
};
const IdeaContext = createContext<IdeaContextType>(IdeaContextDefaultValues)
const IdeaContextProvider: React.FC = ({ children }) => {
const [ideas, setIdeas] = useState<Array<Idea>>(
IdeaContextDefaultValues.ideas);
useEffect( ()=> {
console.log('getting info')
setIdeas(getIdeas())
}, [])
useEffect( () => {
console.log('idea change: ', ideas)
}, [ideas])
return (
<IdeaContext.Provider value={{ ideas, setIdeas }}>
{children}
</IdeaContext.Provider>
);
};
Displayer and Card Component
import React, { FC, ReactElement, useContext } from "react";
import IdeaCreator from "./IdeaCreator";
import { IdeaContext } from "./IdeaContext";
import { Idea } from "../t";
import { Link } from "react-router-dom";
const IdeaPost:React.FC<Idea> = ({title, keyID, description}):ReactElement => {
console.log('Received',title,description,keyID)
return (
<div className="max-w-sm rounded overflow-hidden shadow-lg">
<img
className="w-full"
src="#"
alt="Oopsy daisy"
/>
<div className="px-6 py-4">
<div className="font-bold text-xl mb-2"> <Link to={"ideas/" + keyID} key= {keyID}> {title}</Link> </div>
<p className="text-gray-700 text-base">{description}</p>
</div>
</div>
);
};
const IdeaDisplay:FC<any> = (props:any):ReactElement => {
const { ideas, setIdeas } = useContext(IdeaContext)
console.log('Ideas in display: ', ideas)
console.log('test') //This is what I comment and uncommend to get it to show
return (
<div className="flex flex-wrap ">
{ideas.map((idea) => {
console.log(idea)
console.log('Sending',idea.title,idea.description,idea.keyID)
console.log(typeof idea.keyID)
return (
<IdeaPost
title={idea.title}
description={idea.description}
keyID = {idea.keyID}
key = {idea.keyID * 100}
/>
);
})}
</div>
);
};
export default IdeaDisplay;
Solution Code:
import React, { createContext, useEffect, useState } from "react";
import { IdeaContextType, Idea } from "../t";
import {ideasRef} from './firebase'
async function getIdeas() {
var arr: Array<Idea> = [];
const snapshot = await ideasRef.once("value");
snapshot.forEach((idea) => {
const obj = idea.val();
arr.push({
title: obj.title,
description: obj.description,
keyID: obj.keyID,
});
console.log(arr);
});
return arr
}
const IdeaContextDefaultValues: IdeaContextType = {
ideas: [],
setIdeas: () => {},
};
const IdeaContext = createContext<IdeaContextType>(IdeaContextDefaultValues)
const IdeaContextProvider: React.FC = ({ children }) => {
const [ideas, setIdeas] = useState<Array<Idea>>(
IdeaContextDefaultValues.ideas);
useEffect(() => {
console.log("getting info");
const setup = async () => {
const ideas = await getIdeas();
setIdeas(ideas);
};
setup()
}, []);
useEffect( () => {
console.log('idea change: ', ideas)
const updateDatabase = async () => {
await ideasRef.update(ideas)
console.log('updated database')
}
updateDatabase()
}, [ideas])
return (
<IdeaContext.Provider value={{ ideas, setIdeas }}>
{children}
</IdeaContext.Provider>
);
};
export {IdeaContext, IdeaContextProvider}

First of all you would need to use once and not on if you want to get the data only once. If you want to use a realtime listener you could send the setIdeas to your function. Also try to be carefull with async/away calls to the Firebase sdk. Your code could look like this:
import React, { createContext, useEffect, useState } from "react";
import { IdeaContextType, Idea } from "../t";
import { ideasRef } from "./firebase";
async function getIdeas() {
var arr: Array<Idea> = [];
const snapshot = await ideasRef.once("value");
let items = snapshot.val();
snapshot.forEach((idea) => {
const obj = idea.val();
arr.push({
title: obj.title,
description: obj.description,
keyID: obj.keyID,
});
console.log(arr);
});
return arr;
}
const IdeaContextDefaultValues: IdeaContextType = {
ideas: [],
setIdeas: () => {},
};
const IdeaContext = createContext < IdeaContextType > IdeaContextDefaultValues;
const IdeaContextProvider: React.FC = ({ children }) => {
const [ideas, setIdeas] =
useState < Array < Idea >> IdeaContextDefaultValues.ideas;
useEffect(() => {
console.log("getting info");
const getData = async () => {
const ideas = await getIdeas();
setIdeas(ideas);
};
}, []);
useEffect(() => {
console.log("idea change: ", ideas);
}, [ideas]);
return (
<IdeaContext.Provider value={{ ideas, setIdeas }}>
{children}
</IdeaContext.Provider>
);
};