Provide a better way for users to modify hawtconfig.json

[tadayosi]

See: #2603

Currently users need to unzip hawtio.war and pack it again to modify hawtconfig.json:
https://access.redhat.com/documentation/en-us/red_hat_fuse/7.4/html/managing_fuse/manage-monitor-fuse-karaf#fuse-console-branding-karaf

There should be a more sophisticated way for users to customise the configurations.

[abkieling]

@tadayosi I think we could leverage the existing io.hawt.system.ConfigManager class to customize hawtconfig.json. It supports both System properties and JNDI, right? We could either create a single property pointing to an external version of hawtconfig.json or multiple properties customizing specific fields. Customizing images is a bit tricky because the new image would need to be placed inside the hawtio jar/war or served by an external Web server.

[tadayosi]

@akieling That's an idea, but hawtconfig.json is also read from hawtio-core so we might need to find a way to influence the front-end component hawtio-core from the server-side config properties.

Another option might be to use the custom plugin mechanism:
https://github.com/hawtio/hawtio/blob/master/examples/simple-plugin/src/main/webapp/plugin/simplePlugin.js
and invoke hawtioPluginLoader.registerPreBootstrapTask() there to let users directly modify window['hawtconfig'] programmatically. ... Wait, it sounds like it's already possible?

The Login component doesn't share the same code with hawtio-core config-loader.ts so we have to modify it to fully support the way anyway, though.
https://github.com/hawtio/hawtio/blob/hawtio-2.8.0/hawtio-console-assembly/app/src/login/login.component.ts#L21-L29

[tadayosi]

Note also that hawtio-online and hawtio-operator depend on hawtconfig.json as well. I'm not sure if the current custom plugin mechanism works well with hawtio-online & hawtio-operator, and if there's even need for customising hawtconfig.json. But I assume it's just a matter of modifying the hawtconfig.json config map so it's already sophisticated enough on OpenShift? @astefanutti WDYT?

[astefanutti]

@tadayosi yes, hawtio-online relies on hawtconfig.json as a config map. If hawtio-operator is used to deploy Hawtio Online, the operator watches changes to the config map and automatically triggers a rolling update, so that the changes are taken into account automatically.

[abkieling]

@tadayosi Let me just share an alternative idea. What about creating a Servlet filter that intercepts the request to hawtconfig.json and customizes it before it gets sent back to the browser? The customization values would come from a file on disk, System variables, environment variables, etc.

[tadayosi]

@akieling That sounds good too. Let's provide both ways then. By the way, another thing the custom plugin approach is good at is that the custom plugin provides a place to put other brand related resources such as images and css. The system properties approach might be easier for users but it seems to be still awkward for providing the brand related resources.

Is there anything you're concerned about the custom plugin approach? Such as security issues, and so on?

[abkieling]

@tadayosi No concerns at all. You know better than me what type of customization the customers want to do. If they want to change images, then the system properties approach loses some of its benefits due to the need to serve the images from somewhere else or unzip Hawtio to add the images.

[tadayosi]

My branding-plugin looks ok for the purpose:
https://github.com/hawtio/hawtio/tree/master/examples/branding-plugin
so let me close this issue.

Alex's idea of using a ServletFilter is recorded to #2609.

[osmanates]

Sorry to revive an old thread. But i couldn't make it work with a spring boot jar project. Where do i need to put my customized hawtconfig.json file in a spring boot jar to make it work?

[tadayosi]

@osmanates Can you file a new issue for your question? I'm willing to help you there. First you can check this example btw: https://github.com/hawtio/hawtio/tree/hawtio-2.10.0/examples/springboot-authentication