Introduction

RockScript is scripting engine to coordinates service invocations. You write scripts that invoke services. The RockScript engine executes the scripts resilient and non-blocking.

RockScript is the better alternative for using message queues. When you want to combine multiple service invocations you can’t use plain code because your server could crash while some invocations have succeeded and some may not have started yet. The typical way to deal with this is message queues. But using message queues, you have to cut your code into individual message handlers, configure your code to queues and it quickly becomes really hard to understand the overall logic. With RockScript it’s easy to read your business logic in the scripts.

Because RockScript does persistent, non-blocking execution of service functions, they can be long running. Service function invocations can take seconds to days or even months without any problem. No memory or thread resources are consumed by the RockScript server while waiting for a service function to complete.

Because RockScript language is a subset of JavaScript, it’s really easy to perform data transormations between service function invocations.

For more reasons why and when to use RockScript, see Why and when

Overview

The RockScript language is a subset of JavaScript. For example:

var http = system.import('rockscript.io/http');
var approvalService = system.import('localhost:3000');

/* get is a service function on the built-in http service */
var chuckResponse = http.get({url:'http://api.icndb.com/jokes/random'});

/* approve is a service function on the external approval service */
approvalService.approve(chuckResponse.body.value.joke);

The RockScript server is the server that manages scripts, script versions and script executions.

The RockScript server has a HTTP web API to

• Manage scripts
• Manage script versions
• Start script executions
• Query events, script executions, scripts and script versions

There is a command line interface which you can use to call the API and SPI through the command line.

Services make functionality available through service functions that can be invoked from the scripts. The first and most common service is the HTTP service which comes out of the box.

The RockScript server also has a HTTP Service SPI to add new service functions really fast and easy.

Terminology

A script on the server can be identified by its name and has multiple script versions.

Deploying a script means saving the script on the server so that script executions can be started for that script. A script execution is one execution of a script version.

A service makes external API, system, service or functionality available as functions in the RockScript engine. A service function is a single RCP style operation that can be invoked in the script like a normal function.

A service object, like eg http and approvalService in the example above, is the script object that exposes the service functions in the script.

Thanks

Thanks to GitHub for hosting the code, community and website.

Thanks to JetBrains for their support to open source and the free Intellij IDEA Ultimate license.

Thanks to Travis CI for their continuous integration