controllers.js

function WSTestCtrl($scope, ws) {
    $scope.method = 'ping'
    $scope.params = '[]'

    $scope.reply = 'None yet.'
    $scope.reply_class = 'info'

    $scope.go = function(){
        ws.call($scope.method, JSON.parse($scope.params)).then(function(d){
            $scope.reply = JSON.stringify(d)
            $scope.reply_class = 'success'
        }, function(e){
            $scope.reply = JSON.stringify(e)
            $scope.reply_class = 'danger'
        })
    }
}

services.js

werfns.factory('ws', ['$q', '$location', '$rootScope', function($q, $location, $rootScope) {
    var callbacks = {}
    var current_cb_id = 0
    var ready = false

    if ($location.protocol() == 'https') {
        url = 'wss://' + window.location.hostname + '/ws'
    } else {
        url = 'ws://' + window.location.hostname + ':10000'
    }
    var ws = new WebSocket(url)

    ws.onopen = function(){
        console.debug("WS ready")
        ready = true
    }

    ws.onmessage = function(msg) {
        var reply = JSON.parse(msg.data)
        console.debug("Received data from websocket: ", reply)
        if (!!reply['id']) {
            if(!!reply['error']) {
                console.debug("Firing callback with error", reply['error'])
                $rootScope.$apply(callbacks[reply.id].cb.reject(reply.error))
            }

            if(!!reply['result']) {
                console.debug("Firing callback with result", reply['result'])
                $rootScope.$apply(callbacks[reply.id].cb.resolve(reply.result))
            }

            delete callbacks[reply.id]
        } else {
            console.error('Got a reply without ID:', reply)
        }
    }

    return {
        call: function(method, params) {
            var request = {
                "jsonrpc": "2.0",
                "method": method,
                "params": params
            }

            current_cb_id += 1
            request.id = current_cb_id

            var defer = $q.defer()
            callbacks[request.id] = {
                time: new Date(),
                cb: defer
            }
            console.debug("Sending request", request, ready)
            if (!ready) { console.error('WS not ready!'); }
            ws.send(JSON.stringify(request))
            return defer.promise
        },

        notify: function(method, params) {
        }
    }
}])

wstest.html

<h3>WebSocket Test</h3>

<div class="row">
    <div class="col-lg-5 panel panel-info">
        <div class="panel-heading">Request</div>
        <p><input type="text" ng-model="method" placeholder="method"/></p>
        <p><textarea cols="40" rows="10" ng-model="params"></textarea></p>
    </div>

    <div class="col-lg-2" align="center">
        <button class="btn btn-large btn-primary" ng-click="go()">Go!</button>
    </div>

    <div class="col-lg-5 panel" ng-class="'panel-' + reply_class">
        <div class="panel-heading">Reply</div>
        {{ reply }}
    </div>
</div>