Entities ​

Let's start coding the app by defining the Task entity class.

The Task entity class will be used:

• As a model class for client-side code
• As a model class for server-side code
• By remult to generate API endpoints, API queries, and database commands

The Task entity class we're creating will have an auto-increment id field a title field and a completed field. The entity's API route ("tasks") will include endpoints for all CRUD operations.

Define the Model ​

1. Create a shared folder under the src folder. This folder will contain code shared between frontend and backend.

2. Create a file Task.ts in the src/shared/ folder, with the following code:

// src/shared/Task.ts

import { Entity, Fields } from "remult"

@Entity("tasks", {
  allowApiCrud: true
})
export class Task {
  @Fields.autoIncrement()
  id = 0

  @Fields.string()
  title = ""

  @Fields.boolean()
  completed = false
}

3. In the server's api module, register the Task entity with Remult by adding entities: [Task] to an options object you pass to the remultExpress() middleware:

// src/server/api.ts

import { remultExpress } from "remult/remult-express"
import { Task } from "../shared/Task"

export const api = remultExpress({
  entities: [Task]
})

The @Entity decorator tells Remult this class is an entity class. The decorator accepts a key argument (used to name the API route and as a default database collection/table name), and an options argument used to define entity-related properties and operations, discussed in the next sections of this tutorial.

To initially allow all CRUD operations for tasks, we set the option allowApiCrud to true.

The @Fields.autoIncrement decorator tells Remult to automatically generate an id using the databases's auto increment capabilities.

The @Fields.string decorator tells Remult the title property is an entity data field of type String. This decorator is also used to define field-related properties and operations, discussed in the next sections of this tutorial and the same goes for @Fields.boolean and the completed property.

Test the API ​

Now that the Task entity is defined, we can start using the REST API to query and add a tasks.

1. Open a browser with the url: http://localhost:3002/api/tasks, and you'll see that you get an empty array.

2. Use curl to POST a new task - Clean car.

curl http://localhost:3002/api/tasks -d "{\"title\": \"Clean car\"}" -H "Content-Type: application/json"

3. Refresh the browser for the url: http://localhost:3002/api/tasks and see that the array now contains one item.

4. Use curl to POST a few more tasks:

curl http://localhost:3002/api/tasks -d "[{\"title\": \"Read a book\"},{\"title\": \"Take a nap\", \"completed\":true },{\"title\": \"Pay bills\"},{\"title\": \"Do laundry\"}]" -H "Content-Type: application/json"

• Note that the POST endpoint can accept a single Task or an array of Tasks.

5. Refresh the browser again, to see that the tasks were stored in the db.

Display the Task List ​

Let's start developing the web app by displaying the list of existing tasks in a Vue component.

Replace the contents of src/App.vue with the following code:

// src/App.vue

<script setup lang="ts">
import { onMounted, ref } from "vue";
import { remult } from "remult";
import { Task } from "./shared/Task";

const taskRepo = remult.repo(Task);
const tasks = ref<Task[]>([]);
onMounted(() => taskRepo.find().then((items) => (tasks.value = items)));
</script>
<template>
  <div>
    <h1>todos</h1>
    <main>
      <div v-for="task in tasks">
        <input type="checkbox" v-model="task.completed" />
        {{ task.title }}
      </div>
    </main>
  </div>
</template>

Here's a quick overview of the different parts of the code snippet:

• taskRepo is a Remult Repository object used to fetch and create Task entity objects.
• tasks is a Task array Vue ref that holds the list of tasks.
• Vue's onMounted hook is used to call the Remult repository's find method to fetch tasks from the server, once when the Vue component is loaded.

After the browser refreshes, the list of tasks appears.