buzzPost.io listener for ServiceNow

This is an example of a simple message listener for ServiceNow built with React.

Update set that includes compiled application and script examples can be downloaded here (update set details explained in medium blog post).

The app listens to a specific buzzPost channel and displays an alert when there is a new message. Channel name defined as follows: serviceNow_instance_URL/user_sys_id

How it works

The application receives three parameters from ServiceNow to identify the channel name to subscribe:

1. Instance URL - this param should be passed to the app in window.prefixID variable.
2. User sys_id - this param the application retrieves from out-of-the-box ServiceNow object window.NOW.user.userID.
3. buzzPost broker URL - this is the host name of the broker server, it's retrieved from window.buzzPostBroker variable. If it is a private secured server, then a secret should be supplied as a URL param as well (e.g. https://hub11.dev-labs.io?secret=XYZ).

Incoming message is always a string.

The application expects that the message is a stringified JSON object that conforms to the following format:

{
    "intent":"danger",        // none, primary, warning, danger, success
    "icon":"flag",            // blueprintjs.com/docs/#icons
    "position" :"top-right",      // top, top-right, top-left, bottom, bottom-right, bottom-left
    "timeout":"0",            // milliseconds, 0 means no timeout
    "message": "Hello World!" // text of the message
}

How to build and deploy

Build the app: npm run build. That command creates a single javascript file in a Dist folder.

To deploy the app into ServiceNow you need to perform a few steps.

First - save the content of javascript file as a style sheet (content_css table) and write down sys_id of a newly created record.

You can now run the app just by navigating to <servicenow_url>/<sys_id>.cssdbx.

ServiceNow Native UI (UI16)

For ServiceNow native UI (UI16) load the application with the following global UI script ("Global" set to "true"):

function init(){
	var top = window.top;
	if (typeof top.isListenerLoaded != 'undefined' || top.NOW.user_name=="guest") {
		return;
	}
	top.buzzPostBroker = "https://hub11.dev-labs.io?secret=XYZ";
	top.prefixID = location.hostname;
	injectJS();
}

function injectJS(){
	var appScript = document.createElement('script');
	appScript.src = "6e84be251bca181001e1751bdd4bcbeb.cssdbx"; // here goes your sys_id of the style sheet/app
	top.document.getElementsByTagName('head')[0].appendChild(appScript);
	console.log('%c buzzPost: dependencies injected into global scope','color:blue');
	var checkGlobalFlag = window.top;
	checkGlobalFlag.isListenerLoaded = true;	
}
init();

Service Portal

To run the app in Service Portal you just need to load the app (javascript file) as a part of Service Portal theme or widget.