Rendering custom properties from jbake.properties into Thymeleaf or markdown templates

[ottlinger]

I'd like to render my own properties into thymeleaf template files (the variable is correctly injected into asciidoc documents but does not work in thymeleaf template files)

Example

My jbake.properties contains:

foo_version=0.1.2-SNAPSHOT

and my menu.thyme tries to reference this in a menu item header:

<li><a th:with="rootpath=(${content.rootpath != null} ? ${content.rootpath} : '')" th:href="${rootpath}+'apidocs/index.html'" th:text="'Javadoc '+ ${foo_version} +' (external)'"></a></li>

but is rendered as

Javadoc null (external)

What do I do wrong? Is that a missing feature in jbake 2.5.0 or do I have to add another configuration optional to allow parsing self-defined variables?

BTW: I can easily reference

in Markdown and Asciidoc files and the variable is substituted as expected.

Thanks for any hint

[ancho]

Hi. You can reference configurations with configuration.[option]. In your case configuration.foo_version. See http://jbake.org/docs/2.5.0/#global

[ottlinger]

Thanks @ancho, after changing the template to:

<li><a th:with="rootpath=(${content.rootpath != null} ? ${content.rootpath} : '')" th:href="${rootpath}+'apidocs/index.html'" th:text="'Javadoc '+ ${configuration.foo_version} +' (external)'"></a></li>

the baking does not work and yields:

	at org.jbake.template.ThymeleafTemplateEngine.renderDocument(ThymeleafTemplateEngine.java:79)
	at org.jbake.template.DelegatingTemplateEngine.renderDocument(DelegatingTemplateEngine.java:65)
	at org.jbake.app.Renderer.render(Renderer.java:207)
	... 6 more
Caused by: ognl.OgnlException: source is null for getProperty(null, "foo_version")
	at org.thymeleaf.standard.expression.OGNLShortcutExpression.evaluate(OGNLShortcutExpression.java:89)
	at org.thymeleaf.standard.expression.OGNLVariableExpressionEvaluator.executeExpression(OGNLVariableExpressionEvaluator.java:310)
	at org.thymeleaf.standard.expression.OGNLVariableExpressionEvaluator.evaluate(OGNLVariableExpressionEvaluator.java:170)

Any ideas?

[ancho]

Hmm....have you tried to rename the property to foo.version in jbake.properties?

[ottlinger]

@ancho the references get resolved in markdown and asciidoc, only Thymeleaf seems to be problematic :-( That's why I thought I need to set an "enabling" property in jbake.properties for Thymeleaf, but did not find any.

BTW: Changing the property to foo.version seems to introduce a hierarchy and the error message changes to:

Caused by: ognl.OgnlException: source is null for getProperty(null, "foo")
	at org.thymeleaf.standard.expression.OGNLShortcutExpression.evaluate(OGNLShortcutExpression.java:89)

[ancho]

Ahh. Ok. I didn't get that. Sorry.

[ottlinger]

@ancho I rechecked my repository:

• Asciidoc injection works with:

jbake.properties:
asciidoctor.attributes.export=true
foo_version=0.1.2-SNAPSHOT

example in adoc:
<version>{foo_version}</version>

while markdown and thymeleaf do neither work with/out the configuration prefix.

Is there a config option I missed? Thanks.

[ancho]

@ottlinger have you updated your project to jbake 2.5.0? notice that the version of thymeleaf is 3.0.2.

According to the documentation http://www.thymeleaf.org/doc/tutorials/3.0/usingthymeleaf.html#more-on-texts-and-variables you need to access variables with a tag attribute like th:text or th:utext.

I tried it with the following tag in a thymeleaf footer template like:

<p>foo version: <span th:text='${config.foo_version}'>1234</span></p>

Set foo_version=1.0.0-alpha in the jbake.properties file. And it rendered like expected to <p>foo version: <span>1.0.0-alpha</span></p>.

Compare your templates to the example project https://github.com/jbake-org/jbake-example-project-thymeleaf.

I hope that helps.

[ottlinger]

@ancho Thanks for your help, again - I thought to have tried this option before, maybe ran into caching issues. The prefix config. allows injection of the variable into thymeleaf files.

Is there a simple/same way to do this in markdown? Neither prefix nor maven syntax with dollar seems to work. All I see is the version placeholder in my generated md file.

[ancho]

I don't think so. The MarkdownEngine doesn't seem to handle variables.
Maybe another markdown parser like flexmark-java implements something like that.

As pegdown has a big fat deprecation notice we should change it anyways....

[ottlinger]

ok - can't be helped at the moment. At least Asciidoc and Thymeleaf work properly. I'm going to raise a PR updating the documentation to make this more clear.

@ancho thanks for figuring this out.

[ancho]

Nice. Thank you. I opened an issue to evaluate a new markdown parser. See #327

[jonbullock]

Looks like @acho has solved the initial query - thanks for that :)

To clarify properties in the configuration are made available to all of the template engines via the config. prefix. However Asciidoctor does allow you to inject attributes so that are available when the AsciiDoc content is processed as well.