In this post, we will write a simple TODO app using Remix and Serverless Redis (Upstash).
Remix is a full stack web framework that lets you focus on the user interface and work back through web fundamentals to deliver a fast, slick, and resilient user experience.
Create Remix project
Run the below command:
npx create-remix@latest
The project is ready. Now let's install the dependencies and run:
npm install
npm run dev
The User Interface
We will build a simple form and a list for todo items:
// app/routes/index.tsx
import type { ActionFunction, LoaderFunction } from "remix";
import { Form, useLoaderData, useTransition, redirect } from "remix";
import { useEffect, useRef } from "react";
import type { Todo } from "~/components/todo-item";
import TodoItem from "~/components/todo-item";
export const loader: LoaderFunction = async () => {
// example data
return [
{ id: 1, text: "Task 1", status: false },
{ id: 2, text: "Task 2", status: true },
];
};
export const action: ActionFunction = async ({ request }) => {
// this will be used for create, update and delete operations
};
export default function Index() {
// for loading and form actions
const transition = useTransition();
// to use the loaded data in the page
const todos: Todo[] = useLoaderData();
const isCreating = transition.submission?.method === "POST";
const isAdding = transition.state === "submitting" && isCreating;
// split the finished and unfinished items
const uncheckedTodos = todos.filter((todo) => !todo.status);
const checkedTodos = todos.filter((todo) => todo.status);
const formRef = useRef<HTMLFormElement>(null);
const inputRef = useRef<HTMLInputElement>(null);
useEffect(() => {
// reset the form after the create
if (isAdding) return;
formRef.current?.reset();
inputRef.current?.focus();
}, [isAdding]);
return (
<main className="container">
{/* crete form */}
<Form ref={formRef} method="post">
<input
ref={inputRef}
type="text"
name="text"
autoComplete="off"
className="input"
placeholder="What needs to be done?"
disabled={isCreating}
/>
</Form>
{/* uncompleted tasks */}
<div className="todos">
{uncheckedTodos.map((todo) => (
<TodoItem key={todo.id} {...todo} />
))}
</div>
{/* completed tasks */}
{checkedTodos.length > 0 && (
<div className="todos todos-done">
{checkedTodos.map((todo) => (
<TodoItem key={todo.id} {...todo} />
))}
</div>
)}
</main>
);
}
Here is our TODO component:
// app/components/todo-item.tsx
import { Form } from "remix";
export type Todo = { id: string; text: string; status: boolean };
export default function TodoItem({ id, text, status }: Todo) {
return (
<div className="todo">
<Form method="put">
{/* this hidden input will keep the data for our todo item */}
<input
type="hidden"
name="todo"
defaultValue={JSON.stringify({ id, text, status })}
/>
{/* Remix forms are just like traditional web forms. I like this. */}
<button type="submit" className="checkbox">
{status && "✓"}
</button>
</Form>
<span className="text">{text}</span>
</div>
);
}
Now it is time to add our CSS file. Create a css file app/styles/app.css:
:root {
--rounded: 0.25rem;
--rounded-md: 0.375rem;
--gray-50: rgb(249, 250, 251);
--gray-100: rgb(243, 244, 246);
--gray-200: rgb(229, 231, 235);
--gray-300: rgb(209, 213, 219);
--gray-400: rgb(156, 163, 175);
--gray-500: rgb(107, 114, 128);
--gray-600: rgb(75, 85, 99);
--gray-700: rgb(55, 65, 81);
--gray-800: rgb(31, 41, 55);
--gray-900: rgb(17, 24, 39);
}
*,
::before,
::after {
box-sizing: border-box;
border: 0;
padding: 0;
}
button,
input,
optgroup,
select,
textarea {
font-family: inherit;
font-size: 100%;
line-height: inherit;
color: inherit;
margin: 0;
padding: 0;
}
button {
cursor: pointer;
background-color: white;
}
html {
font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, Segoe
UI, Roboto, Helvetica Neue, Arial, Noto Sans, sans-serif,
Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji;
line-height: 1.5;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
color: var(--gray-800);
}
.container {
padding: 8rem 1rem 0;
margin: 0 auto;
max-width: 28rem;
}
.input {
width: 100%;
padding: 0.75rem 1rem;
background-color: var(--gray-100);
border-radius: var(--rounded-md);
}
.input::placeholder {
color: var(--gray-400);
}
.input:disabled {
color: var(--gray-600);
background-color: var(--gray-200);
}
.todos {
margin-top: 1.5rem;
}
.todos.todos-done {
background-color: var(--gray-100);
color: var(--gray-500);
border-radius: var(--rounded-md);
}
.todo {
display: flex;
align-items: center;
padding: 0.75rem;
border-radius: var(--rounded-md);
}
.todo + .todo {
border-top: 1px solid var(--gray-100);
}
.todo .checkbox {
display: flex;
align-items: center;
justify-content: center;
width: 1.25rem;
height: 1.25rem;
border-radius: var(--rounded);
border: 1px solid var(--gray-300);
box-shadow: 0 1px 1px 0 rgb(0 0 0 / 10%);
}
.todo .text {
margin-left: 0.75rem;
}
Import the css under root.tsx:
import {
Links,
LiveReload,
Meta,
Outlet,
Scripts,
ScrollRestoration,
} from "remix";
import type { MetaFunction } from "remix";
import styles from "./styles/app.css";
export function links() {
return [{ rel: "stylesheet", href: styles }];
}
export const meta: MetaFunction = () => {
return { title: "Remix Todo App with Redis" };
};
export default function App() {
// ...
}
Now you should see:
Prepare the database
We will keep our data in Upstash Redis. So create an Upstash database. We will use HTTP based Upstash client. Let's install:
npm install @upstash/redis
:::note Upstash is compatible with Redis API, so you can use any Redis client but you need to change the below code. :::
We can add new TODO items by just submitting the form. We save the new items to Redis Hash.
Copy/paste
UPSTASH_REDIS_REST_URLveUPSTASH_REDIS_REST_TOKENfrom Upstash console.
// app/routes/index.tsx
// ...
import { Redis } from "@upstash/redis";
const redis = new Redis({
url: "UPSTASH_REDIS_REST_URL",
token: "UPSTASH_REDIS_REST_TOKEN",
});
export const action: ActionFunction = async ({ request }) => {
const form = await request.formData();
if (request.method === "POST") {
const text = form.get("text");
if (!text) return redirect("/");
await redis.hset("remix-todo-example", {
[Date.now().toString()]: {
text,
status: false,
},
});
}
// to fetch the list after each operation
return redirect("/");
};
// ...
Now let's list the items:
// app/routes/index.tsx
export const loader: LoaderFunction = async () => {
const res = await redis.hgetall<Record<string, object>>(DATABASE_KEY);
const todos = Object.entries(res ?? {}).map(([key, value]) => ({
id: key,
...value,
}));
// sort by date (id=timestamp)
return todos.sort((a, b) => parseInt(b.id) - parseInt(a.id));
};
We have 'create' and 'list' functionality. Now we will implement the part where the user can mark a todo item as done.
// app/routes/index.tsx
export const action: ActionFunction = async ({ request }) => {
const form = await request.formData();
// create
if (request.method === "POST") {
// ...
}
// update
if (request.method === "PUT") {
const todo = form.get("todo");
const { id, text, status } = JSON.parse(todo as string);
await redis.hset("remix-todo-example", {
[id]: {
text,
status: !status,
},
});
}
return redirect("/");
};
Now everything is ready! I am planning to implement the same TODO application with Next.js and SvelteKit. Then I will compare my experience in these frameworks.
Stay tuned and follow us at on Twitter and Discord.
Project Source Code
https://github.com/upstash/redis-examples/tree/master/remix-todo-app-with-redis