Re: Detect invalid directives

On 19 Oct 2011, at 14:46, Daniel Dekany <[email protected]> wrote:

> Wednesday, October 19, 2011, 2:11:51 PM, John Todd wrote:
> 
>> On 10/19/11 04:29, Daniel Dekany wrote:
>>> Wednesday, October 19, 2011, 5:55:18 AM, John Todd wrote:
>>> 
>>>> Hello,
>>>> 
>>>>  I would like to handle invalid directives however they are just
>>>> passing through the templating engine as text, e.g. using the following
>>>> FTL "blah.ftl":
>>>> 
>>>> This is [#blah]content[/#blah].  This is [#fu] content.
>>> That's not possible, unless you pre-process the templates with a
>>> custom TemplateLoader that replaces "[#blah]" with "[[#-- --]#blah]"
>>> or like.
>>> 
>>> Out of curiosity, why do you need this?
>> We use the templating engine extensively for on-demand personalization
>> of content and would like to reject templating requests at the time the
>> template is passed to our system if the template contains unknown
>> directives and just reject the request.
>> 
>> So, you're saying it's not possible to catch such exceptions or the
>> behavior I'm seeing is not possible?
> 
> Sorry, I was hasty and misread your question. FreeMarker should throw
> exception for invalid # tags always and everywhere. However, now that
> I have tried this, it seems it bypasses the # tags until it finds one
> that it knows. It's astonishing that I have never ran into this bug
> myself, and it's quite concerning that the author didn't have a test
> case that catches this. I suppose it slipped in when tag-syntax
> detection was added. It can't be straight fixed in 2.3.x as it would
> be non-BC, except by adding some new option. The workaround for this
> right now is starting all templates with [#ftl]...

Is this only for the square bracket syntax? It makes sense to start the template with [#ftl] anyway, instead of relying on auto-detection...

-- Denis. 

> 
>> thx,
>> jt
>> 
>>>> and the code:
>>>> 
>>>> public class App {
>>>> 
>>>>    public static void main(String[] args) throws Exception {
>>>>        Configuration cfg = new Configuration();
>>>>        cfg.setTagSyntax(Configuration.SQUARE_BRACKET_TAG_SYNTAX);
>>>> 
>>>>        cfg.setDirectoryForTemplateLoading(new
>>>> File(System.getProperty("user.dir")));
>>>> 
>>>>        System.out.println("Compiling template: blah.ftl");
>>>>        FileReader reader = new
>>>> FileReader(System.getProperty("user.dir") + "/blah.ftl");
>>>>        // Expect ParseException
>>>>        Template template = new Template("blah.ftl", reader, cfg);
>>>> 
>>>>        System.out.println("Getting template from Configuration.");
>>>>        // Also expect ParseException
>>>>        template = cfg.getTemplate("blah.ftl");
>>>>        StringWriter writer = new StringWriter();
>>>>        template.process(new HashMap(), writer);
>>>>        System.out.println("Output: " + writer.toString());
>>>>    }
>>>> }
>>>> 
>>>> I get the output:
>>>> 
>>>> This is [#blah]content[/#blah].  This is [#fu] content.
>>>> 
>>>> In each Template reference, I'm expecting a compilation error w/
>>>> "Unknown directive" per the FMParser.jj grammar.  Any suggestions?
>>>> 
>>>> Thanks,
>>>> 
>>>> John T.
>> 
>> 
>> ------------------------------------------------------------------------------

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