Tab Atkins Jr. schrieb:
On Sun, Oct 18, 2009 at 12:25 PM, Aryeh Gregor <simetrical+...@gmail.com> wrote:
Some attention needs to be given to error handling. What happens if
one or more of the requested id's aren't found? Do they silently
fail? If so, this could result in the link doing absolutely nothing
in hard-to-control situations -- like an error page that occurs
sporadically, say a 500. Do they trigger a normal page load? If so,
they have to wait until the entire page has loaded, which would be bad
user experience but hard to track down -- a long, inexplicable delay
followed by everything working normally. This could be mitigated by
having an HTTP header to say "that id doesn't exist, load the whole
page instead", but it would fail in the default case (standard HTTP
server unaware of new feature).
Also, what happens if some of the given id's are present, but not others?
I'll think a bit about these issues today. I'm not sure, off the top
of my head, what the best response is.
What do you think about:
1. Defining which ids are to be replaced:
- The list of IDs to replace is in <base> tag, as described earlier in
this thread. <a> and <form> elements can have a boolean @onlyreplace
attribute that specifically enables or disables the functionality for
the element.
- If at least one of the IDs is found in the linked document, replace
the IDs that are found. Ignore IDs that are not present in the linked
document, or in the document that contains the link (important for
dynamic applications, so the <head> section is not forced to know the
state of the <body>).
- If none of the indicated IDs are found, *replace the whole page*. This
makes it possible to prevent e.g. a wiki or forum from being
@onlyreplaced by just using different IDs.
2. Possible further additions to the base tag:
- Explicitly exclude parts of a site from @onlyreplace, e.g.:
<base onlyreplaceExcludeDir="/wiki /forum /media/downloads">
- Explicitly specify the links that carry the onlyreplace feature:
<base onlyreplaceLinkContainers="navigation orderform">
When we add more attributes to <base> than just href and target, the
sentence "There must be no more than one base element per document." in
4.2.3 of the spec should maybe be removed, as for every possible
attribute in <base> there will be a note anyway saying "If there are
multiple base elements with [attributename] attributes, all but the
first are ignored."
