AsyncComponentMixin.js

var AsyncStateManager = require('../managers/asyncStateManager');
var AsyncComponentMixin = {
    componentWillMount: function AsyncComponentMixin_componentWillMount() {

        var self = this;
        var asyncStateGetter = this.constructor.getInitialAsyncState;
        var asyncStateKey = asyncStateGetter.name;

        // ====> AsyncStateManager should not be module / global, it should be tied to request
        if ( AsyncStateManager.hasData(asyncStateKey) ) {
            self.setState(AsyncStateManager.getData(asyncStateKey));
        } else {
            AsyncStateManager.queueAsyncData(asyncStateKey, function() {
                return self.constructor.getInitialAsyncState(self.props.params, self.props.query);
            });

        }
    }

};

module.exports = AsyncComponentMixin;

serverRender.js

var app = App();

function getMarkup() {
    var deferred = {
        resolve: null,
        reject: null
        },
        promise = new Promise(function(resolve, reject) {
          deferred.resolve = resolve;
          deferred.reject = reject;
        });

    singleRun(deferred);
    return promise;
}

function singleRun(deferred) {
    var markup = React.renderComponentToString(app);
    if (AsyncStateManager.hasRunningAsyncs()) {
        AsyncStateManager.onQueueDrain(function() {
            singleRun(deferred);
        });
    } else {
        deferred.resolve(markup);
    }
}

getMarkup().then(function(markup) {
    console.log(markup);
}, function(err) {
    console.log("Errror", err);
});