Using JavaScript in Mirth® Connect

This section shows you how to use JavaScript to perform various messaging operations within Mirth® Connect.

About E4X
Accessing Message Data with E4X
Adding Segments to a Message
Segments are a group of fields that can contain varying types of data. Each segment exists independently and can be used in multiple messages.
Deleting a Segment
Iterating Over Message Segments
Iterating Over Repeating Fields
Adding a New Repeating Field
Message Variables
Built-In Code Templates
Using Java Classes
Regular Expressions
Logging with JavaScript
Generating a Hash with JavaScript
How to generate a hash using Javascript.

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Mirth® Connect by NextGen Healthcare User Guide

Using the JavaScript Editor

Mirth® Connect has a rich JavaScript editor that includes automatic code completion, code folding, multi-line tabs/comment toggles, auto-indentation, bracket matching, macros, and much more. Using the Context Menu in the JavaScript Editor Remapping Editor Shortcut Keys Using the Auto-Completion Popup in the JavaScript Editor Using the Context Menu in the JavaScript Editor Using the Auto-Completion Popup in the JavaScript Editor Remapping Editor Shortcut Keys Parent topic: Mirth Connect and JavaScript

Mirth® Connect by NextGen Healthcare User Guide

Mirth® Connect Debugger

The Mirth Connect Debugger tool allows you to troubleshoot JavaScript errors throughout the Mirth® Connect application. The Debugger can be used for the following scripts and connectors: Deploy, Undeploy, Preprocessor, and Post Processor scripts Attachment/Batch scripts Source Connectors: Filters/Transformers Database Reader and JavaScript Reader types Destination Connectors: Filters/Transformers. Database Writer and JavaScript Writer types Response transformers Before You Begin If your Java application does not interact directly with a user, use the following steps to change the Headless mode to false. Setting this mode to false means that your Java application: Displays windows or dialog boxes. Accepts keyboard or mouse input. Uses any heavyweight AWT (Abstract Windowing Toolkit) components. To Edit the mcserver.vmoptions file Use the Debugger Debugger Window Debugger Menus Parent topic: Mirth Connect and JavaScript

Mirth® Connect by NextGen Healthcare User Guide

Attachment JavaScript Functions

Attachment Handlers are used to extract a portion of a message (or the entire message) and store it separately as an attachment. The portion of the message that was extracted is replaced with an attachment replacement token. When you use a destination connector to send a message downstream, Mirth® Connect will automatically take the message and replace any attachment tokens with the actual attachment data (unless you have Reattach Attachments turned off in the Destination Settings) . Throughout the message lifecycle you can retrieve, modify, and add new attachments with built-in helper functions. Built-In Attachment Functions The AttachmentUtil Class The Attachment Object Examples Built-In Attachment Functions The AttachmentUtil Class The Attachment Object Examples Parent topic: Mirth Connect and JavaScript

Mirth® Connect by NextGen Healthcare User Guide

Mirth® Connect and JavaScript

JavaScript is a scripting language that can be used in a wide variety of places throughout Mirth® Connect to perform advanced routing and transformation. About JavaScript Using JavaScript in Mirth Connect Using the JavaScript Editor Variable Maps Attachment JavaScript Functions The User API (Javadoc) The user API (application programming interface) is a collection of Java classes and methods that helps you interact with channels and the message that is being processed. Mirth Connect Debugger

Mirth® Connect by NextGen Healthcare User Guide

Logging with JavaScript

Use logger.info() and logger.error() to log information in JavaScript contexts: logger.info("The value of x =" + x); You can view the output of this method in the Mirth® Connect Dashboard's Server Log. The default logging level, ERROR, is the quickest, having the least amount of overhead. INFO and DEBUG levels give more details but have more overhead, so are somewhat slower. You can change the logging level via the Mirth® Connect Server Manager for users who run the latest version of Mirth® Connect on a Mac ( Applications > Mirth Connect > mcmanager) or PC: Note: Mirth Appliance users can change the logging level from the Mirth® Connect Settings page via Applications > Mirth Connect > Manage from the Appliance UI. Parent topic: Using JavaScript in Mirth Connect

Mirth® Connect by NextGen Healthcare User Guide

Accessing Message Data with E4X

<?xml version="1.0"?><HL7Message> <MSH> <MSH.1>|</MSH.1> <MSH.2>|^~\&</MSH.2> <MSH.3> <MSH.3.1>SENDAPP</MSH.3.1> </MSH.3> <MSH.4> <MSH.4.1>General Hospital</MSH.4.1> </MSH.4> <MSH.5> <MSH.5.1>RECAPP</MSH.5.1> </MSH.5> <MSH.6/>… </MSH>…</HL7Message> The XML variables msg and tmp represent root-level elements. Use JavaScript bracket notation for each element level in the document below the root (this works with any message data, not only HL7): var sendingFacility = msg ['MSH']['MSH.4'][MSH.4.1'].toString(); Most values in an HL7 message go three levels deep. The first level is a segment; the second level is a field within the segment; the third level is a component within a segment field. If a field or component does not exist, it is created automatically. Examples for repeating segments and fields include using bracket notation to index: var obx = msg['OBX'];var obx5 = obx['OBX.5'];var obx5_1 = obx5['OBX.5.1'].toString(); All E4X methods available on the msg and tmp variables can be