[Immagination running freely, I do not have a lot of experience designing syntax, but I suffer a lot in a helpdeskish way trying to explain syntax to users. Hopefully this can be somehow useful]
> we also have to reach consensus on the filtering algorithm. for > instance, should we simply require that a url passes all the > filtering > rules to allow its download (just like the current -A/R > behaviour), or > should we instead adopt a short circuit algorithm that > applies all rules > in the same order in which they were given in the command line and > immediately allows the download of an url if it passes the > first "allow" > match? should we also support apache-like deny-from-all and > allow-from-all policies? and what would be the best syntax to trigger > the usage of these policies? > Get the best of both, use a syntax permitting a "first match-exits" ACL, single ACE permits several statements ANDed together. Cooking up a simple syntax for users without much regexp experience won't be easy. One way (probably not the most beautiful syntax) could be a running number, AND together repeated filters with the same number but use FIRST MATCH between numbers: download every path containing download on every *.dom.com (including sweets.dom.com); OTHERWISE avoid anything (else) on sweets.dom.com; OTHERWISE from peanuts.dom.com get everything except brown stuff (currants and so on); OTHERWISE get peanuts from everywhere else --filter1+=+domain:.+\.dom\.com --filter1=+path:download && --filter2-=+domain:sweets\.dom\.com && --filter3+=+peanuts\.dom\.com --filter3=-file:brown && --filter4+=+path:peanuts && (&& omitted later on) The first filterX (for every X) does carry a +/- before the = (permit/deny ACE), every filterX does carry a + or - after the = (what are whe matching). Well, I wrote the example and I hate it already, hopefully some better syntax comes up which doesn't require nested quotes. Require an additional switch permit/deny for every ACE: --filter1=permit --filter1=+domain:.+\.dom\.com --filter1=+path:download --filter2=deny --filter2=+domain:sweets\.dom\.com --filter3=permit --filter3=+peanuts\.dom\.com --filter3=-file:brown --filter4=permit --filter4=+path:peanuts With permit and + as default that would make --filter1=domain:.+\.dom\.com --filter1=path:download --filter2=deny --filter2=domain:sweets\.dom\.com --filter3=peanuts\.dom\.com --filter3=-file:brown --filter4=path:peanuts On the other hand, without the default=permit we could loose the numbers (use position): --filter=permit --filter=+domain:.+\.dom\.com --filter=+path:download --filter=deny --filter=+domain:sweets\.dom\.com --filter=permit --filter=+peanuts\.dom\.com --filter=-file:brown --filter=permit --filter=+path:peanuts e.g. start with permit or deny (or default permit for first ACE only), following statements are ANDed together as a single ACE until next permit/deny. Considering command line restrictions and so on for complicated expression there should also be a --filter-file=filename, same syntax except the --filter ? I realize much of this syntax can be thrown out of the window simply considering we can probably reach the same effect with uri filters and more complicated regexp (perl5 syntax): --filter=+uri:.+\.dom\.com/*.download --filter=-domain:sweets\.dom\.com --filter="+uri:peanuts\.dom\.com/.*(?!brown)" --filter=+path:peanuts Simpler and shorter invocation syntax, but more complicated regexp requirement, not a simple thing for the casual user, after all wget doesn't try to appeal to programmers only, many examples in the manual will be neccessary. BTW any comments about the dots ? Requiring escaped dots in domains would become old really fast, reversing behaviour (\. = any char) would be against the principle of least surprise, since any other regexp syntax does use the opposite. Either way pure windows users will be confused (*.html instead of .*\.html), but personally I don't think permitting yet another alternate syntax (using globs) is justified, and a syntax using exclusively globs would be too limited. Heiko -- -- PREVINET S.p.A. www.previnet.it -- Heiko Herold [EMAIL PROTECTED] [EMAIL PROTECTED] -- +39-041-5907073 / +39-041-5917073 ph -- +39-041-5907472 / +39-041-5917472 fax
