ThymeleafViewResolver does not pick up cache/cacheLimit from properties

[mmoayyed]

The auto configuration for the ThymeleafViewResolver does:

ThymeleafViewResolver resolver = new ThymeleafViewResolver();
resolver.setTemplateEngine(this.templateEngine);
resolver.setCharacterEncoding(this.properties.getEncoding().name());
resolver.setContentType(appendCharset(this.properties.getContentType(),
                    resolver.getCharacterEncoding()));
resolver.setExcludedViewNames(this.properties.getExcludedViewNames())

The resolver also has setters for cache and cachelimit which are not taken into account from the properties. The resolver as such always ends up caching views, it seems.

[snicoll]

The cache is managed by the TemplateResolver created in the same auto-configuration class.

Did you run in an actual problem? From your description, it's not really clear if you're guessing or you're actually having a problem.

[mmoayyed]

I did run into a problem. I am not sure if what I am doing is purely incorrect and can be done in a better way, but here is what I have as a sample:

1. Class A extends ThymeleafViewResolver
2. Class A also has ThymeleafViewResolver autowired in as field, via boot.
3. When resolving a view, if certain conditions are not met, delegate to the super.
4. When resolving a view, if certain conditions are met, handle directly.

So, what in order to correctly initialize A as a resolver, I added a PostConstruct method to A to set fields, based on the autowired ThymeleafViewResolver. This allows me to set the template engine and locale and a bunch of other settings on A, that were autowired from the actual ThymeleafViewResolver instance.

This presented the problem/bug, where views seemed always cached by the resolver because ThymeleafViewResolver.isCached() always returned true, and the ThymeleafViewResolver .getCacheLimit() was always > 0.

[snicoll]

What I can see is that you are using a customization of the view resolver and that use cases works fine without the customization. If you want us to look into it, we need a way to make the link between the customization and the issue you're experiencing. Can you share a sample that exhibits the problem?

[mmoayyed]

Happy to remove it, if I can.

Here is the code: https://github.com/Unicon/cas/blob/letsboot/cas-server-webapp-themes/src/main/java/org/jasig/cas/services/web/RegisteredServiceThemeBasedViewResolver.java

[mmoayyed]

Also, perhaps a related yet different issue is boot does not allow me to create something like this: https://github.com/Unicon/cas/blob/letsboot/cas-server-webapp-config/src/main/java/org/jasig/cas/config/CasProtocolViewsConfiguration.java#L212

Which I have had to do in order to compress whitespace that is left by thymeleaf. It would be best actually if boot could do this automatically for me, via a prop, etc.

[mmoayyed]

In the first link, this is the bit that does the job:

        setCache(this.properties.isCache());
        if (!isCache()) {
            setCacheLimit(0);
        }

[philwebb]

I think not setting the cache property on ThymeleafViewResolver is probably a bug, we do it for all other template auto-configurations.

[snicoll]

Indeed, we do it for the ThymeleafResolver but it looks like we forgot to do it for ThymeleafViewResolver.

[wilkinsona]

We don't have a property for cache limit, so I'm only going to apply the spring.thymeleaf.cache property to the auto-configured ThymeleafViewResolver.