Executing JavaScript on application load

Question

Hi all, 
 I'm working on a scenario where, upon opening the Appian application in the user's browser, we need to execute JavaScript to retrieve an XML file containing contextual data from external Proteo 4 applications. The goal is to use this data to continue the process in Appian with all relevant information from the previous application, without having to pass everything through query parameters. 
 What the client wants to achieve: 
 
 Execute JavaScript or listen to window events when the Appian application (or interface) loads. 
 Retrieve an XML context file based on an ID passed via the URL. 
 Convert this XML to JSON so Appian can consume the relevant data. 
 Store and use this contextual data within Appian to restore or continue the user's workflow seamlessly. 
 
 Has anyone encountered a similar situation where JavaScript execution or window event handling was needed to retrieve external contextual data on Appian startup? How did you approach it? Are there any best practices, workarounds, or patterns you can recommend? 
 Any advice or shared experience would be greatly appreciated! 
 Thanks in advance.

Stefan Helzle · Answer

This would require a custom component plugin.

Harsha Sharma · Answer

You might want to explore Appian RPA to listen to window events and then fetch the XML content. RPA can help get the data into Appian which you can use further in workflow.

Shubham Aware · Answer

First you might already know that, You can't run JavaScript in interfaces.
I would recommend give a try, Use Integration to call Proteo 4 API with the Id from URL query parameter. Parse XML to JSON in the integration or expression rule.
https://docs.appian.com/suite/help/25.3/url-parameters.html#