This repository now host multiple npm packages under one roof:
- monaco-languageclient to connect Monaco editor with language servers.
- vscode-ws-jsonrpc which implements communication between a jsonrpc client and server over WebSocket.
- monaco-editor-react makes editor and languageclient available within a react component.
- monaco-languageclient-examples provides the examples which allows to use them externally.
The examples not requiring a backend are now available via GitHub Pages.
- Monaco Language Client, VSCode WebSocket Json RPC, Monaco Editor React and examples
- Official Documentation
- Changelogs, current versions and compatibility table
- Getting started
- Usage
- Examples Overview
- Main Examples
- JSON Language client and language server example (Location)
- Python Language client and pyright language server example (Location)
- Groovy Language client and language server example (Location)
- Java Language client and language server example (Location)
- Cpp / Clangd (Location)
- Application Playground (Location)
- Langium grammar DSL (Location)
- Statemachine DSL (created with Langium) (Location)
- Browser example (Location)
- Purely monaco-editor related examples
- Server processes
- Verification Examples & Usage
- VSCode integration
- Main Examples
- Featured projects
- Troubleshooting
- Licenses
Since monaco-languageclient
version 10 we started to build an official documentation. This will be continuously extended.
We added a migration guide with the release of monaco-languageclient
version 10
.
CHANGELOGs for each project are available from the linked location:
- CHANGELOG for
monaco-languageclient
is found here - CHANGELOG for
vscode-ws-jsonrpc
is found here - CHANGELOG for
@typefox/monaco-editor-react
is found here - CHANGELOG for
monaco-languageclient-examples
is found here
Important Project changes and notes about the project's history are found here.
These are the current versions of packages from this repository and their alignment with @codingame/monaco-vscode-api monaco-editor and vscode:
- monaco-languageclient:
10.0.0
(release date: unreleased) - @typefox/monaco-editor-react:
7.0.0
(release date: unreleased) - Aligned with:
- @codingame/monaco-vscode-[editor]-api:
^21.1.0
- vscode:
1.104.1
- monaco-editor:
0.53.0
- @codingame/monaco-vscode-[editor]-api:
- vscode-ws-jsonrpc:
3.5.0
(release date: 2025-08-11)
Check find the full compatibility table with all previous versions.
On your local machine you can prepare your dev environment as follows. At first it is advised to build everything. Locally, from a terminal do:
git clone https://github.com/TypeFox/monaco-languageclient.git
cd monaco-languageclient
npm i
# Cleans-up, compiles and builds everything
npm run build
Start the Vite dev server. It serves all client code at localhost. You can go to the index.html and navigate to all client examples from there. You can edit the client example code directly (TypeScript) and Vite ensures it automatically made available:
npm run dev
# OR: this clears the cache and has debug output
npm run dev:debug
As this is a npm workspace the main package.json contains script entries applicable to the whole workspace like watch
, build
and lint
, but it also contains shortcuts for launching scripts from the childe packages like npm run build:examples
.
If you want to change the libries and see this reflected directly, then you need to run the watch command that compiles all TypeScript files form both libraries and the examples:
npm run watch
Please look at the respective section in the packages:
- Usage for
monaco-languageclient
is found here - Usage for
vscode-ws-jsonrpc
is found here - Usage for
@typefox/monaco-editor-react
is found here
The examples demonstrate mutliple things:
- How
monaco-languageclient
is use bymonaco-edtior-wrapper
or@typefox/monaco-editor-react
to have an editor that is connected to a language server either running in the browser in a web worker orvscode-ws-jsonrpc
. is used to an external process via web-socket. - How different language servers can be intergrated in a common way, so they can communicate via web-socket to the front-end running in the browser.
JSON Language client and language server example (Location)
The json-server runs an external Node.js Express app where web sockets are used to enable communication between the language server process and the client web application (see JSON Language Server). The json-client using extended mode as editor app which connects to the language server and therefore requires the node server app to be run in parallel. The json-client using classic mode as editor app which connects to the language server and therefore requires the node server app to be run in parallel.
Python Language client and pyright language server example (Location)
The python-server runs an external Node.js Express app where web sockets are used to enable communication between the language server process and the client web application (see Pyright Language Server). The python-client contains the editor app which connects to the language server and therefore requires the node server app to be run in parallel. It is also possible to use a @typefox/monaco-editor-react app to connect to the server. Both versions now feature a debugger, see here.
Groovy Language client and language server example (Location)
The groovy-server runs an external Java app where web sockets are used to enable communication between the language server process and the client web application (Groovy Language Server). The groovy-client contains the editor app which connects to the language server and therefore requires the node server app to be run in parallel.
Java Language client and language server example (Location)
The java-server runs an external Java app where web sockets are used to enable communication between the language server process and the client web application (Java Language Server). The java-client contains the editor app which connects to the language server and therefore requires the node server app to be run in parallel.
Langium examples (here client and server communicate via vscode-languageserver-protocol/browser
instead of a web socket used in the three examples above
Cpp / Clangd (Location)
It contains both the language client and the langauge server (web worker). The clangd language server is compiled to wasm so it can be executed in the browser. Heads up: This is a prototype and still evolving.
Application Playground (Location)
This example uses the view service provider from @codingame/monaco-vscode-editor-api
to build an application that utilizes more vscode features. Heads up: This is a prototype and still evolving.
Langium grammar DSL (Location)
It contains both the language client and the langauge server (web worker). Here you can chose beforehand if the wrapper should be started in classic or extended mode.
Statemachine DSL (created with Langium) (Location)
It contains both the language client and the langauge server (web worker). It is also possible to use a @typefox/monaco-editor-react app to connect to the server.
Browser example (Location)
This demonstrates how an editor app can be combined with a language service written in JavaScript. This example can now be considered legacy as the web worker option eases client side language server implementation and separation, but it still shows a valid way to achieve the desired outcome.
See Typescript Language support.
For the json-client, react-client or the client-webpack examples you need to ensure the json-server example is running:
# start the express server with the language server running in the same process.
npm run start:example:server:json
For the python-client example you need to ensure the python-server example is running:
# start the express server with the language server running as external node process.
npm run start:example:server:python
If you want to use the debugger in the python-client example you need to the debugger is running. You require docker-compose to run it. From the project root run docker-compose -f ./packages/examples/resources/debugger/docker-compose.yml up -d
. First start up will take longer as the container is downloaded from GitHub's container registry. Use docker-compose -f ./packages/examples/resources/debugger/docker-compose.yml down
to stop it.
For the groovy-client example you need to ensure the groovy-server example is running. You require docker-compose which does not require any manual setup (OpenJDK / Gradle). From the project root run docker-compose -f ./packages/examples/resources/groovy/docker-compose.yml up -d
. First start up will take longer as the container is downloaded from GitHub's container registry. Use docker-compose -f ./packages/examples/resources/groovy/docker-compose.yml down
to stop it.
For the java-client example you need to ensure the java-server example is running. You require docker-compose which does not require any manual setup (OpenJDK / Eclipse JDT LS). From the project root run docker-compose -f ./packages/examples/resources/eclipse.jdt.ls/docker-compose.yml up -d
. First start up will take longer as the container is downloaded from GitHub's container registry. Use docker-compose -f ./packages/examples/resources/eclipse.jdt.ls/docker-compose.yml down
to stop it.
None of the verification examples is part of the npm workspace. Some bring substantial amount of npm dependencies that pollute the main node_modules dependencies and therefore these examples need to be build and started independently. All verifaction examples re-uses the code form the json client example and therefore require the json server to be started.
-
vite verification example demonstrates how bundling can be achieved with vite. There is no configuration required Please do:
cd verify/vite && npm run verify
. It serves the client here: http://localhost:8081. -
webpack verification example demonstrates how bundling can be achieved with webpack. You find the configuration here: webpack.config.js. Please do:
cd verify/webpack && npm run verify
. It serves the client here: http://localhost:8082. -
Next.js verification example: demonstrates how to use
@typefox/monaco-editor-react
with Next.js, Please do:cd verify/next && npm run verify
. It serves the client here: http://localhost:8083. -
Currently broken and not usable until repaired: Angular verification example: Before March 2024 this was located in a separate repository. If you want to test it, Please do:
cd verify/angular && npm run verify
. It serves the client here: http://localhost:4200.
You can as well run vscode tasks to start and debug the server in different modes and the client.
- JSONA Editor: Showcase (GitHub)
- Clangd in Browser: Showcase (GitHub)
- Langium minilogo using monaco-editor-wrapper: Showcase (GitHub)
For troubleshooting, please also see the Troubleshooting Guide.