Re: AMP pages with Tapestry

Carlos Montero Canabal <[email protected]> Wed, 30 Nov 2016 14:18:54 +0100
Newsgroups	gmane.comp.java.tapestry.user
Message-ID	<[email protected]>
Thank you for the response.

AMP validation is very restrictive, so I need write <html amp> only, not <html amp=“amp”> or <html amp=“true”>.

So, I go for other fast solution which I use in other project to generate emails.

I will show the extended solution in my  tapestry5.dev-util.com <http://tapestry5.dev-util.com/> webapp, but as a short summary:

AmpPage.java

@Inject
private Block head, body;

...

AmpPage.tml

!doctype html>
<html
	xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd"
	xmlns:p="tapestry:parameter">

<t:block t:id="head">
<head>
 ...
</head>
</t:block>

<t:block t:id="body">
<body>
 ...
</body> 
</t:block>
</html>

<t:delegate to="block:head"/>
<t:delegate to="block:body"/>

</html>

So AmpPage is the “real" page but it has invalid AMP attributes. So I created a AmpExporterPage:

public class AmpExporterPage {

	@Inject
	private PartialTemplateRenderer partialTemplateRenderer;

	@Inject
	private ComponentSource componentSource;

	@Inject
	private Request request;

	@Inject
	private Environment environment;

	public Object onActivate(final EventContext ec) {

		return new StreamResponse() {

			@Override
			public void prepareResponse(final Response response) {

			}

			@Override
			public InputStream getStream() throws IOException {

				final AmpPage ampPage = (AmpPage) componentSource.getPage(AmpPage.class);
				ampPage.onActivate(ec);
				ampPage.setupRender();
				final Block head = ampPage.getHead();
				final Block body = ampPage.getBody();
				
				environment.push(Heartbeat.class, new HeartbeatImpl());

				String markupHead = partialTemplateRenderer.render(head);
				String markupBody = partialTemplateRenderer.render(body);
				
				markupHead = markupHead.replace(" xmlns=\"http://www.w3.org/1999/xhtml\"", "");
				markupHead = markupHead.replaceAll("amp-boilerplate=\"amp-boilerplate\"", "amp-boilerplate");

				markupBody = markupBody.replace(" xmlns=\"http://www.w3.org/1999/xhtml\"", "");
				
				final StringBuilder sb = new StringBuilder();
				sb.append("<!doctype html><html amp>").append(markupHead).append(markupBody).append("</html>");
				final InputStream is = new ByteArrayInputStream(sb.toString().getBytes("UTF-8"));
				
				return is;
			}

			@Override
			public String getContentType() {
				return "text/html";
			}
		};
	}

}

I do a speed test and it takes around 40 milliseconds in generate de response, so it’s ok for me.

Regards

Carlos Montero


> El 30/11/2016, a las 14:06, Thiago H. de Paula Figueiredo <[email protected]> escribió:
> 
> On Tue, Nov 29, 2016 at 6:36 PM, Carlos Montero Canabal <
> [email protected]> wrote:
> 
>> Hello Tapestry users,
>> 
> 
> Hi!
> 
> 
>> 
>> I would like to create an amp version of my pages into a tapestry5.4
>> webapp. According to https://www.ampproject.org/
>> docs/reference/spec#required-markup <https://www.ampproject.org/
>> docs/reference/spec#required-markup> the root html only would be:
>> 
>> <html amp>
>> 
>> Tapestry5 make a xhtml compilation for the .tml, so I ask you if there is
>> any method to:
>> 
> 
> That's not correct. Tapestry 5 uses an XML parser for template files, and
> attributes without values aren't valid XML. You can try <html amp="amp">.
> 
> 
>> 1. Exclude de xhtml compilation for this pages
>> 2. Intercept the result and modify it to eliminate additional tags added
>> by Tapestry.
>> 3. Create a MarkupModel for AMPHtml?
>> 
> 
> Number 3 above is probably the best idea. You'll need to override the
> MarkupWriterFactory so you can use your AmpMarkupModel.
> 
> --
> Thiago