Telnet Demo

This repository contains an Isolated Web App that allows the user to connect to a TCP/IP server through an interactive terminal. In other words, a Telnet client. This provides a demonstration of the Direct Sockets API.

Privacy

This application is served statically and is cached for offline use. No analytics are collected. All communication is directly between the client and the remote server specified by the user.

Building

This project is written in TypeScript and uses npm and Webpack to manage dependencies and automate the build process. To get started clone the repository and install dependencies by running,

npm install

Chrome supports two options for Isolated Web App development. In "proxy" mode you run a local development server as you would for normal web app development on a URL like http://localhost:8080. When the app is installed a random isolated-app:// origin is created and the browser proxies requests for this origin to your local server. This allows you to quickly edit and refresh the app to see your changes. When developer mode is enabled Chrome also allows you to self-sign a Web Bundle and load it as it would be for a production app.

These instructions have been tested on Chrome 110.0.5464.2. When developing an Isolated Web App always make sure you are running the latest version of Chrome dev-channel as the feature is under active development.

Running with a local development server

To start a local development server run,

npm run start

The server is listening on http://localhost:8080. The next step is to launch Chrome to install the app in "proxy" mode,

google-chrome-unstable --enable-features=IsolatedWebApps,IsolatedWebAppDevMode \
                       --install-isolated-web-app-from-url=http://localhost:8080

If you visit chrome://apps you will see a new app called "Telnet".

After installation you can remove the --install-isolated-web-app-from-url parameter from the command line.

Note that flags must be provided on the command line when the browser first starts. Once it is running launching it from the command line will open a new window but command line flags will not take effect.

Webpack's automatic reloading will not work because it does not support Trusted Types.

Building a Signed Web Bundle

Signing a Web Bundle requires generating a private key. This only needs to be done once,

openssl genpkey -algorithm ed25519 -out private.pem

To build,

npm run build

This will generate dist/telnet.swbn, a Web Bundle signed with the development key generated above.

To install this bundle as an Isolated Web App, launch Chrome with the following flags,

google-chrome-unstable --enable-features=IsolatedWebApps,IsolatedWebAppDevMode \
                       --install-isolated-web-app-from-file=$PWD/dist/telnet.swbn

If you visit chrome://apps you will see a new app called "Telnet".

After installation you can remove the --install-isolated-web-app-from-file parameter from the command line.

Note that flags must be provided on the command line when the browser first starts. Once it is running launching it from the command line will open a new window but command line flags will not take effect.