Using Grails GSP as a Spring Boot templating engine (in a non-Grails app)

[U47]

It looks like there was a Maven dependency org.grails:grails-gsp-spring-boot that may have been a means to get GPS views into a Spring Boot (non-Grails) application.

I see that remnants still exist in the source (GspAutoConfiguration.java) that might be the ticket to an autoconfigured Spring Boot templating enging for GSPs. It doesn't appear that there are Maven dependencies to target this anymore, particularly since Grails moved to Apache.

Does anyone have any advice on whether using GSP as a templating engine in a Spring Boot app is possible, and how that might best be configure?

TIA.

[chrismalan]

This is an interesting question. I would also like to know how to use GSP pages as a templating engine in Spring Boot. The Fields plugin always causes me problems when wanting to modify produced pages, especially f:table ones.

[jdaugherty]

We moved the code over but did not publish because of numerous code smells. We had hoped to refactor GSP so that it could be properly included in a spring only app. I think there is an example test app that is Spring only, but we didn't want to publish and commit to that yet. We are open source - pull requests are welcome in this area.

[U47]

I appreciate the response, James.

I was able to build the grails-gsp-spring-boot starter, and with a bit of cajoling was able to get it to parse a .gsp as a view. Unfortunately, you're right about the code smells. The example app already had allow-bean-definition-overriding: true and I needed to add allow-circular-reverences: true as well just to get it to work at all, both of which are red flags. Plus, the GspAutoConfiguration is kinda barfing all over the Spring Boot configuration trying to handle not being in a Grails app by creating and registering a standalone Grails app, which in turn is griefing the existing Spring Boot and Spring MVC beans and contexts. It was not able to register the gspViewResolver automatically, and I wasn't able to manually register it properly either.

All in all, I think GSPs are a good fit for a Groovy-based Spring Boot/Spring MVC app, especially considering the canned support for Groovy's TemplateEngine. When you factor in the possibilities of using Grails' SpringSec taglib, Asset Pipeline, and other niceties, that's compelling. However, there evidently isn't enough traction to make this supported and maintained, and I don't have the skillset or bandwidth to take it on.

Maybe it will find a champion someday.