Creating a basic plugin

This guide will show you how to create a simple, basic plugin that will let the users insert timestamps into their content. This is a beginner-friendly tutorial, perfect for your first interaction with the CKEditor 5 framework. While it is not necessary to be familiar with the CKEditor 5 Crash course to follow it, you should consider reading that one, too.

We will create a toolbar button that will insert the current date and time at the caret position into the document. If you want to see the final product of this tutorial before you plunge in, check out the live demo below.

# Let’s start!

The easiest way to get started is to grab the starter project using the commands below.

npx -y degit ckeditor/ckeditor5-tutorials-examples/timestamp-plugin/starter-files timestamp-plugin
cd timestamp-plugin

npm install
npm run dev

This will create a new directory called timestamp-plugin with the necessary files. The npm install command will install all the dependencies, and npm run dev will start the development server.

The editor with some basic plugins is created in the main.js file.

# Creating a plugin

All features in the CKEditor 5 are powered by plugins. To create our custom timestamp plugin, we need to import the base Plugin class from the ckeditor5. Be careful not to remove the other imports from this package.

import {
    // Other imports
    Plugin
} from 'ckeditor5';

We can now create a Timestamp class that extends the basic Plugin class. After we define it, we can add it to the editor’s plugins array.

class Timestamp extends Plugin {
    init() {
        console.log( 'Timestamp was initialized.' );
    }
}

ClassicEditor
    .create( document.querySelector( '#editor' ), {
        licenseKey: 'GPL', // Or '<YOUR_LICENSE_KEY>'.
        // Add the Timestamp plugin to config.plugins array.
        plugins: [
            Essentials, Paragraph, Heading, List, Bold, Italic, Timestamp
        ]
    } );

The development server will refresh. The initialization of the timestamp plugin should be visible. You should see this in the browser (on the left) and the browser’s development console (on the right):

# Registering a toolbar button

CKEditor 5 has a rich UI library. We will grab the ButtonView class for our toolbar button from there.

Once we create a new instance of ButtonView, we will be able to customize it by setting its properties. We will create a label, which will be visible on the button thanks to the withText property.

We also need to register our button in the editor’s UI componentFactory, so it can be displayed in the toolbar. To do it, we will pass the name of the button in the componentFactory.add method, to be able to add it into the toolbar array.

import { 
    // Other imports
    ButtonView
} from 'ckeditor5';

import 'ckeditor5/ckeditor5.css';

class Timestamp extends Plugin {
    init() {
        const editor = this.editor;
        // The button must be registered among the UI components of the editor
        // to be displayed in the toolbar.
        editor.ui.componentFactory.add( 'timestamp', () => {
            // The button will be an instance of ButtonView.
            const button = new ButtonView();

            button.set( {
                label: 'Timestamp',
                withText: true
            } );

            return button;
        } );
    }
}

ClassicEditor
    .create( document.querySelector( '#editor' ), {
        licenseKey: 'GPL', // Or '<YOUR_LICENSE_KEY>'.
        plugins: [
            Essentials, Paragraph, Heading, List, Bold, Italic, Timestamp
        ],
        // Add the Timestamp button to the config.toolbar array.
        toolbar: [
            'heading', 'bold', 'italic', 'numberedList', 'bulletedList', 'timestamp'
        ]
    } )
    .then( editor => {
        console.log( 'Editor was initialized', editor );
    } )
    .catch( error => {
        console.error( error.stack );
    } );

Now, you should be able to see the Timestamp button. It does not do anything just yet, so let’s change that.

# Inserting a timestamp

We can now define the core functionality of our plugin – the action that should be executed once our button is clicked.

To insert anything into the document structure, we need to change the model using the model’s change() method. This way we get access to the model writer.

We will use the insertContent() method to insert our timestamp into the document. Inside, we just need to create a new text node with the writer.createText() method.

class Timestamp extends Plugin {
    init() {
        const editor = this.editor;
        // The button must be registered among the UI components of the editor
        // to be displayed in the toolbar.
        editor.ui.componentFactory.add( 'timestamp', () => {
            // The button will be an instance of ButtonView.
            const button = new ButtonView();

            button.set( {
                label: 'Timestamp',
                withText: true
            } );

            // Execute a callback function when the button is clicked.
            button.on( 'execute', () => {
                const now = new Date();

                // Change the model using the model writer.
                editor.model.change( writer => {

                    // Insert the text at the user's current position.
                    editor.model.insertContent( writer.createText( now.toString() ) );
                } );
            } );

            return button;
        } );
    }
}

Well done! You implemented a CKEditor 5 plugin. You should be able to click and see that it works.

# Demo

See the result in action.

# Full code

If you got lost at any point, see the final implementation of the plugin. You can paste the code from main.js, or clone and install the whole thing, and it will run out of the box.

# Adapt this tutorial to CDN

If you want to use the editor from CDN, you can adapt this tutorial by following these steps.

First, clone the repository the same way as before. But do not install the dependencies. Instead, open the index.html file and add the following tags:

<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <title>CKEditor 5 Framework – tutorial CDN</title>
        <link rel="stylesheet" href="https://cdn.ckeditor.com/ckeditor5/44.1.0/ckeditor5.css" />
    </head>
    <body>
        <div id="editor">
            <p>Hello world!</p>
        </div>
        <script src="https://cdn.ckeditor.com/ckeditor5/44.1.0/ckeditor5.umd.js"></script>

        <script type="module" src="/main.js"></script>
    </body>
</html>

The CSS file contains the editor and content styles. Therefore, you do not need to import styles into your JavaScript file.

// Before:
import 'ckeditor5/ckeditor5.css';

// After:
// No need to import the styles.

The script tag loads the editor from the CDN. It exposes the global variable CKEDITOR. You can it in your project to access the editor class and plugins. That is why you must change the import statements to destructuring in the JavaScript files:

// Before:
import { ClassicEditor, Essentials, Bold, Italic, Paragraph } from 'ckeditor5';

// After:
const { ClassicEditor, Essentials, Bold, Italic, Paragraph } = CKEDITOR;

After following these steps and running the npm run dev command, you should be able to open the editor in browser.