Browser-Mirror allows two (or more) remote browsers visiting the same web page to share state without the overhead of screen sharing.

Requirements

• Server
  • A modern version of Node & NPM on a Mac/*nix OS w/ BASH
• Clients
  • HTML5 browsers with support for ECMA6 & Websockets

Quickstart (For Mac & Linux)

Install the server

1. Navigate to where ever you want to install the server.
2. Create a new directory for the server:

mkdir bm-server && cd bm-server

3. Login as root and run the installer:

sudo -s # Login as root if needed
source /dev/stdin <<< "$(curl -s https://raw.githubusercontent.com/Pamblam/browser-mirror/master/installer)"

4. Run bm server start to start the websocket server. You can give it a port number if you want it to run on a port other than 1337 (eg, bm server start 1223)
5. Run bm server stop to stop the server
6. Run bm server logs to view the server logs

Update the server

1. Stop the server bm server stop
2. Update the server bm update
3. Check that you have the latest version with bm --version
4. restart the server bm server start

Run man bm or bm --help for further uses & info.

Implement it

Add the client side JS file to your project, either by running bm client install /path/to/project or download it manually from the git repo, then put in a script tag.

-> Important: This script must be included above all other Javascripts <-

<script src='bm-client.js'></script>

The master page will control all the "slave" pages.

Set up the constructor.

const mirror = BMClient(1, '127.0.0.1', 'master'); 

The parameters are..

1. Any developer specified session identifier. Can be a number or a string.
2. The host where the server is installed.
3. 'master' or 'slave' - there can only be one master per session, but unlimited slaves.
4. If using a port other than 1337, pass it in as the 4th argument.

Listen for errors

mirror.onError(err=>{ 
    // do something with the err
    alert(err.message);
}); 

Listen for confirmation requests

By default, if the app needs to confirm an action with a user it will use the native confirm method. If you want to use your own method you can define it with the onSessionConfirm method.

Your confirmation method will receive a single object with 2 properties. Its message property is the message to be shown to the user. The confim_action is to be passed thru to the return object's action method, which tells the server which confirmation you're responding to.

Your confirmation method must return an object containing two properties:

• confirm: The boolean value of the user's response.
• action: Passed to the function as the confim_action string.

Alternatively, your method may return a Promise which resolves with the above described object.

mirror.onSessionConfirm(data=>new Promise(data=>{
    do_confirm(data.message).then(result=>{
        done({
            confirm: result,
            action: data.confirm_action
        });
    });
}));

Listen for session changes

This is mainly called when someone leaves or joins the session.

mirror.onSessionUpdate(data=>{
    document.getElementById("count").innerHTML = `${data.members} people in the current session`;
});

Connect to the Server

The connect method takes one optional parameter, a number 0, 1, or 2:

• 0 (default) - Do not enforce browser restrictions. This is fine if you use a CSS reset.

• 1 - Force all members to use the same browser as the leader for the best experience.

• 2 - Warn members that are not using the same browser as the leader that they will have a better experience if they use whatever browser the leader is using, but allow them to continue using the browser they're using.

  mirror.connect(2);

Start the Session

Only the master should call the start method, and it should only be called when the session has all it's members. Monitor the data.members on each session update and call start when everyone has joined. Once the start method is called, no others will be allowed to join.

You can optionally pass true into the start method to resize all browsers to match the size of the smallest browser in the session. This is helpful if the page being viewed is responsive or uses percentages for positioning by making sure the mouse cursor is always over the same elements for each of the members.

mirror.start()

Custom session data

You can also broadcast custom data fro the master to each client.

In the master....

mirror.setState({ anything: anything });

in the client....

mirror.onStateChange(state=>console.log(state.anything));

Securing your connection

If your site runs over HTTPS you must secure your websocket connection or none of this will work.

Securing the server

Before starting the server you just have to configure it to use your SSL certificate, key and ca file. If you do not know where these are located read this for some help figuring it out.

From the server machine just run these three commands to provide the server with your certificate info and it will automatically run over a secure connection from then on. Substitute the paths for the paths to your own files.

1. bm set certificate /path/to/my/certificate
2. bm set key /path/to/my/key
3. bm set ca /path/to/my/ca

Securing the client

To secure the client you just instantiate the class with the secure method like so:

const mirror = BMClient(1, '127.0.0.1', 'master').secure();

Everything else works as described above.

TODO

• screencast gif (demo) for readme page