Migrating from Capabilities API to qlik-embed in Angular 19 Mashup – WebSocket Management Concerns

[amj]

Hi everyone,

I'm currently developing a mashup using Angular 19 and Qlik Sense, and I'm considering whether it's worth migrating from the Capabilities API to the newer qlik-embed approach.

While qlik-embed seems more modern and better aligned with Angular's component-based architecture, there are still a few unclear aspects—particularly around WebSocket management and error handling.

With the Capabilities API:

• I can manually manage WebSocket connections (e.g., close them when switching between apps).

• I can also intercept server-side errors sent over WebSocket and handle them in the frontend.

My questions are:

1. How does qlik-embed manage WebSocket connections when switching between apps? Are connections to previously opened apps automatically closed or do they persist?

2. Is there any mechanism for intercepting and handling WebSocket-level errors (like server timeouts or invalid objects) when using qlik-embed, similar to what the Capabilities API allows?

I'd appreciate any insights or official guidance on how these scenarios are handled with qlik-embed. Thanks in advance!

[alex_colombo · Accepted solution]

Hey @amj ,qlik-embed is responsible for render visualizations, and of course, all the apps connected to the visualizations rendered. When qlik-embed component unmounts from the page it will handle all "closing" itself about visualizations.

For managing websockets you should use @qlik/api or enigma.js, with that you can also intercelt websocket errors and other events.

Using both qlik-embed and @qlik/api is the reccommend approach. Per our docs "@qlik/api/qix will re-use existing WebSocket sessions if they are found. It also integrates seamlessly with @qlik/embed libraries and will hook into any WebSocket session already opened by any @qlik/embed library".