func.js

module.exports = function() {
    var azure = require('azure');

    var topic = "foo-bar";
    var connectionString = "Endpoint=sb://";

    console.log("Configuring Service Bus.");
    var serviceBusService = azure.createServiceBusService(connectionString);
    var movies = [];
    for(count = 0; count < 5000; count++) {
        movies.push({id: count});
    }

    var promise = new Promise(function(resolve, reject) {
        serviceBusService.createTopicIfNotExists(topic, function(error) {
            if (error) {
                console.log('failed to get the service bus topic');
                reject();
            }

            var messages = [];

            for(index = 0; index < movies.length; index++) {
                var message = {
                    body: JSON.stringify(movies[index]),
                    customProperties: { 
                        messageNumber: index
                    }
                }

                messages.push(message);
            }
            resolve(messages);
        });
    });
    promise.then(messages => {
        var promises = [];
        while (messages.length > 0) {
            for(index = 0; index < 1000; index++) {
                promises.push(sendMessage(serviceBusService, topic, messages[index]));
            }

            messages.splice(0, 1000);
            Promise.all(promises).then(() => {
                promises = []
            });
        }
    });
}

function sendMessage(serviceBusService, topic, message) {
    return new Promise((resolve, reject) => {
        serviceBusService.sendTopicMessage(topic, message, (error, result) => {
            if (error) {
                console.log(error);
                reject();
            }

            resolve();
        });
    });
}