You clearly know about this more than I do. For legacy issues we cannot change the content-type: text.html but we can change the <!DOCTYPE> in the scaffolding app. As long as there are no major objections I say we should follow your advice. I look forward to your html patches. ;-)
Massimo On Jul 3, 9:19 pm, Jonathan Lundell <jlund...@pobox.com> wrote: > By way of background, web2py generates xhtml pages, with these > doctypes (I'm not clear on why one or the other is chosen; perhaps > someone could enlighten me): > > <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" > "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd > "> > <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" > "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd > " > > The problem is, web2py's xhtml is not, by and large, valid. This ought > to cause a problem, because xhtml parsers aren't allowed to handle > invalid markup. We get away with it because essentially all servers > present our pages as html, not xhtml, and our browsers parse it as > html, which is more forgiving. > > (One of the better explanations of all this is: > <http://webkit.org/blog/2006/09/20/understanding-html-xml-and-xhtml/ > >.) > > Here's an illustration. With a standards-compliant browser (I'm using > Safari 4.0.1 and Firefox 3.5 on OS X), have a look at these pages: > > http://www.web2py.com/examples/spreadsheethttp://lobitos.net/w2p/w2p.htmlhttp://lobitos.net/w2p/w2p.xhtml > > They're identical (I copied the first one, changing only some URLs to > be absolute instead of relative). You should see that your browser > won't display the third version. > > Why? Because the first two are served as "Content-Type: text/html", > while the third is served as "Content-Type: application/xhtml+xml". > This is how Apache handles .html and .xhtml files by default. Notice > that the browser pays attention to the Content-Type header and ignores > the DOCTYPE (the w3 validator looks at DOCTYPE, though). Notice also > that the browser is ignoring the "<meta http-equiv="content-type" > content="text/html; charset=utf-8" />" line; it really does believe > the http header: not the doctype, not the meta. > > So. Why use the XHTML DOCTYPE? The main reason that I can think of is > that the resulting document, if valid, has a DTD and can be parsed as > XML. Not by the browser, which is going to parse it as bad html, but > by someone else, maybe. But that reason only holds water if the > document is actually *valid* xhtml. > > (Another note: this is the spreadsheet application, but the same thing > would happen with many, perhaps most, web2py pages, certainly any with > <form action="">. You can try the same experiment with other pages.) > > What to do? In my view, there's a short-term answer and a long-term > answer. And they're both complicated by legacy compatibility issues, > which I'll take the liberty of ignoring here. > > In the short term, fix the output to be valid XHTML. This is easier if > you use transitional rather than strict. > > In the long term, move to HTML. Given that it looks like XHTML2 has > been abandoned, the future standard is going to be HTML5. Not very > soon, since browsers are only starting to support it, and the FSM only > knows when Microsoft will get around to it, but eventually, since > HTML5 has a lot of nifty features. > > Me, I've settled on HTML4 Transitional for anything I've got control > over, using XHTML only for a couple of pages that I need to parse as > XML. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "web2py Web Framework" group. To post to this group, send email to web2py@googlegroups.com To unsubscribe from this group, send email to web2py+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/web2py?hl=en -~----------~----~----~----~------~----~------~--~---
