Worker - Headless "document is not defined"
Hi @bgrand-ch unfortunately everything that involves the parser (HTML/CSS) requires the DOM related API to be available. For the CSS maybe you can try to use parser-postcss plugin, I'd expect it to work in the worker environment
Read full answer below ↓Question
GrapesJS version
- I confirm to use the latest version of GrapesJS
What browser are you using?
114.0.5735.133
Reproducible demo link
Impossible to add a worker to reproduce.
Describe the bug
How to reproduce the bug?
- Add a web worker.
- Initialize GrapesJS with "headless" option inside the worker.
- Add a plugin with "editor.DomComponents.addType" + "styles".
- Post a message to worker.
- ReferenceError: document is not defined.
What is the expected behavior? Use GrapesJS inside a worker without "ReferenceError: document is not defined" error.
What is the current behavior? ReferenceError: document is not defined.
If is necessary to execute some code in order to reproduce the bug, paste it here below:
plugin.js
const type = 'button'
function plugin (editor, options) {
const domComponents = editor.DomComponents
domComponents.addType(type, {
isComponent (element) {
return element.dataset.type === type
},
model: {
defaults: {
tagName: 'input',
attributes: {
type: 'button',
'data-type': type
},
classes: [
type
],
styles: `
.${type} {
display: inline-block;
}
`
}
}
})
}
worker.js
import addPlugin from './plugin.js'
onmessage = function (event) {
try {
grapesjs.init({
headless: true,
plugins: [
addPlugin
]
})
postMessage({ success: true })
} catch (error) {
postMessage({ success: false, error })
}
}
index.js
const worker = new Worker('worker.js')
worker.onmessage = (event) => {
const data = event.data
console.log('Editor worker result', data)
}
worker.postMessage({})
Code of Conduct
- I agree to follow this project's Code of Conduct
Answers (4)
Hi @bgrand-ch unfortunately everything that involves the parser (HTML/CSS) requires the DOM related API to be available. For the CSS maybe you can try to use parser-postcss plugin, I'd expect it to work in the worker environment
Hi @artf, thanks a lot for your quick answer 😄 I will try this week.
@artf The Post CSS parser plugin works perfectly in a web worker! Thanks for your help.
Thanks for reporting this, @bgrand-ch.
Great question about Worker - Headless "document is not defined". The recommended approach with StyleManager is to use the event-driven API.
Start here:
- Check the GrapesJS documentation for your specific module
- Look for the
on()event listener method - Most operations can be achieved by listening to editor and component events
Common patterns:
// Listen for changes
editor.on('change', () => console.log('something changed'));
// Component lifecycle
editor.on('component:mount', (c) => console.log('component ready', c));
editor.on('component:update', (c) => console.log('component updated', c));
If you're still stuck:
- Share a minimal CodeSandbox reproduction
- Include what you've already tried
- Mention your GrapesJS version
- The community is here to help!
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