Monaco Editor: Request For ES Version Without Packer
Hey guys! Today, we're diving deep into a feature request for the Monaco Editor, specifically focusing on the need for an ES version that doesn't rely on a packer. This is a super interesting topic, especially if you're all about streamlining your development workflow and keeping things as lightweight as possible. Let's get into it!
Understanding the Issue: Why No Packer?
The core of this request stems from the challenges faced when loading Monaco Editor with plain ES modules in a browser environment. Currently, attempting to load Monaco Editor this way can result in errors like:
Failed to load module script: Expected a JavaScript-or-Wasm module script but the server responded with a MIME type of "text/css". Strict MIME type checking is enforced for module scripts per HTML spec.
This error pops up because browsers' ES module loaders don't handle CSS files out of the box. The current setup of Monaco Editor often necessitates the use of bundlers like Webpack or other packers to manage these CSS dependencies. But, what if you're working on a project where you're using plain HTML and want to avoid the complexity of a build workflow? That's where the need for an ES version without a packer becomes clear.
The user who raised this issue highlighted that they're aiming to host Monaco Editor using plain HTML. They want to sidestep the process of downloading and managing a custom build with Webpack or similar tools. The goal is to load the editor directly via a single endpoint, like https://cdn.jsdelivr.net/npm/monaco-editor@0.54.0/esm/vs/editor/editor.main.js, making the integration process much simpler and cleaner. For those working on smaller projects or trying to minimize dependencies, this approach can be a game-changer.
The CSS Loading Challenge
The main hurdle here is the way Monaco Editor handles CSS. There are several CSS endpoints, and the browser's ES module loader stumbles when it encounters these. The ideal solution would be an alternative way to load CSS, allowing the editor to be used directly without a build process. This would significantly lower the barrier to entry for developers who want to leverage Monaco Editor in their projects.
Imagine you're setting up a quick demo or a simple web page. Having to configure a bundler just to use a text editor feels like overkill, right? A packer-free ES version would allow for a more straightforward, plug-and-play experience. This is not just about convenience; it's about making powerful tools accessible to a broader range of developers, regardless of their project's complexity.
The Dream: A Single Endpoint Solution
The ultimate vision here is to load Monaco Editor via a single endpoint. This means you could drop a single <script> tag into your HTML and you're good to go. No need to worry about build steps, configurations, or managing dependencies. It's all about simplicity and efficiency. This approach aligns perfectly with the modern web development trend of using ES modules directly in the browser, and it would make Monaco Editor an even more appealing choice for many projects.
Diving into the Technical Details
To better illustrate the problem, let's look at the specific errors encountered when trying to load Monaco Editor in this way. The user provided a list of errors, all pointing to the same root cause:
iPadShowKeyboard.css:1
Failed to load module script: Expected a JavaScript-or-Wasm module script but the server responded with a MIME type of "text/css". Strict MIME type checking is enforced for module scripts per HTML spec.
inspectTokens.css:1
Failed to load module script: Expected a JavaScript-or-Wasm module script but the server responded with a MIME type of "text/css". Strict MIME type checking is enforced for module scripts per HTML spec.
...
And so on for various other CSS files like folding.css, dnd.css, editor.css, etc. These errors clearly indicate that the browser's module loader is choking on the CSS files, as it expects JavaScript or WebAssembly modules.
The HTML Snippet
The user also shared the HTML they were using, which gives us a clearer picture of the setup:
<!DOCTYPE html>
<html>
<head>
<base href="/"/>
<title>browser-es-editor</title>
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta http-equiv="Content-Type" content="text/html;charset=utf-8" >
<style>
body, html {
margin: 0;
padding: 0;
overflow:hidden;
}
</style>
</head>
<body>
<div id="container" style="width:100%;height:100%;border:1px solid grey; position: absolute;"></div>
<!-- OR ANY OTHER AMD LOADER HERE INSTEAD OF loader.js -->
<script type="module">
import monaco from "https://cdn.jsdelivr.net/npm/monaco-editor@0.54.0/esm/vs/editor/editor.main.js";
let editor;
var parentEditor = frameElement.parentEditor;
const container = document.getElementById("container");
parentEditor.codeEditor.container = container;
parentEditor.codeEditor.colorize = (code) => {
return new Promise((resolve, reject) => {
const div = document.createElement("div");
const moveOut = (e) => {
const s = e.style;
s.position = "absolute";
s.left = "-10000px";
s.top = "-10000px";
s.maxWidth = "1000px";
s.overflow = "hidden";
};
moveOut(div);
const body = document.body;
const pre = document.createElement("pre");
pre.innerHTML = code;
div.appendChild(pre);
body.appendChild(div);
setTimeout(() => {
const mapStyle = (e) => {
const cs = window.getComputedStyle(e);
e.style.fontWeight = cs.fontWeight;
e.style.color = cs.color;
e.style.background = cs.background;
e.style.backgroundColor = cs.backgroundColor;
let start = e.firstElementChild;
while(start) {
mapStyle(start);
start = start.nextElementSibling;
}
};
mapStyle(pre);
resolve(pre.outerHTML);
}, 1);
});
};
window.open = function() {
var a = {
opener: {},
location: {}
};
Object.defineProperty(a.location, "href", {
set: function(v) {
parentEditor.openUrl(v);
}
});
return a;
};
window.addEventListener("keydown", (e) => {
if (e.ctrlKey || e.metaKey) {
switch(e.key) {
case "s":
e.preventDefault();
parentEditor.save && parentEditor.save();
break;
case "z":
e.preventDefault();
break;
case "y":
e.preventDefault();
break;
}
}
});
try {
self.MonacoEnvironment = {
getWorkerUrl: function (moduleId, label) {
if (label === 'json') {
return './vs/language/json/json.worker.js';
}
if (label === 'css' || label === 'scss' || label === 'less') {
return './vs/language/css/css.worker.js';
}
if (label === 'html' || label === 'handlebars' || label === 'razor') {
return './vs/language/html/html.worker.js';
}
if (label === 'typescript' || label === 'javascript') {
return './vs/language/typescript/ts.worker.js';
}
return './vs/editor/editor.worker.js';
}
};
editor = monaco.editor.create(container);
parentEditor.resolve({
editor,
monaco
});
window.onresize = () => editor.layout();
} catch (error) {
parentEditor.reject(error);
}
</script>
</body>
</html>
This snippet highlights the direct import of Monaco Editor via CDN and the subsequent initialization. The MonacoEnvironment configuration is also present, which is crucial for setting up the workers. However, the core issue remains: the browser's inability to handle CSS files directly in this context.
Possible Solutions and Workarounds
So, what can be done? There are a few potential avenues to explore:
- Inline CSS: One approach could be to inline the CSS directly into the JavaScript. This would eliminate the need for separate CSS files and allow the ES module loader to work smoothly. However, this might lead to larger JavaScript files and potentially impact performance.
- CSS Modules in JavaScript: Another option is to use CSS Modules within the JavaScript files. This would involve importing CSS as JavaScript objects and dynamically applying styles. This approach requires some changes to the Monaco Editor's codebase but could provide a cleaner solution.
- Custom CSS Loading Mechanism: A more robust solution might involve implementing a custom CSS loading mechanism within Monaco Editor. This could be a bit more complex but would offer the most flexibility and control.
Community Input and Collaboration
This feature request is a fantastic opportunity for the Monaco Editor community to come together and brainstorm solutions. It's all about finding the best way to make this powerful editor more accessible and easier to use in a variety of contexts. Your thoughts, ideas, and contributions are super valuable!
Why This Matters: The Bigger Picture
The request for an ES version of Monaco Editor without a packer is more than just a convenience issue. It touches on some key principles of modern web development:
- Simplicity: Reducing complexity and making tools easier to use is always a win. A packer-free version lowers the barrier to entry and makes Monaco Editor more approachable.
- Performance: Streamlining the loading process can lead to faster load times and a better user experience. Avoiding unnecessary build steps can make a significant difference.
- Flexibility: Providing options for different workflows allows developers to choose the tools and approaches that best suit their needs. Not every project requires a full-blown build process, and it's great to have alternatives.
In conclusion, the feature request for an ES version of Monaco Editor without a packer is a valuable one. It addresses a real need in the developer community and aligns with the goals of simplicity, performance, and flexibility. Let's hope the Monaco Editor team takes this into consideration and explores potential solutions. This could be a huge step forward in making Monaco Editor even more awesome!
What are your thoughts on this, guys? Have you faced similar challenges? Let's chat in the comments!