Make the logic match the intent described in the comments.
The intent is clearly "accept notices whenever (A or B or C)", but
the logic implemented was more like "not ((not A) or (not B) or (not C))",
which is a basical boolean algebra fail (each of those ORs need to
become ANDs for double-negation to work).
The practical implication was that, for example, writing a reply
to someone else's notice and including an @-reference to _another_
user on another site to bring them into the discussion would
fail to deliver the notice to the new user because their server
would basically say `oh no, you can't message this user
from someone else's thread' because an earlier check for
the `A' or `C' parts of `(A or B or C)' prevents `B' from
being checked.
cf.: <http://status.hackerposse.com/notice/55846>, which was
refused by the nhcrossing.com server because it didn't know
about <http://sn.jonkman.ca/notice/93724>, even though it would
have passed the later `notice contains a reference to a local user'
check if not for an exception being prematurely thrown.
The whole idea of reporting `which specific check FAILED'
in an `if ANY SUCCEEDS' analysis is just bogus, so nix all of
the distinct ClientExceptions--a single `ALL FAILED' exception
is the only one that makes sense.
There was a problem with (specifically at least) PuSHpress for
Wordpress. A previous attempt to perform a DB transaction backfired
because the remote side could connect to the callback before our
commit had gone through.
I take full responsibility for introducing the bug in the first place :)
Among other things (such as permanent subscriptions), Pubsubhubbub 0.4
removed the "sync" verification method. This means that any incoming
PuSH subscription requests that follow the 0.4 spec won't really
_require_that we handle it as a background process, but if we were to
try direct verification of the subscription - and fail - there's no way
we could pick up the ball again. So _essentially_ we require background
processing with retries.
This means we must implement something like the "poorman cron" or
similar, so background processing can be handled
on-demand/on-site-visit. This is how Friendica, Drupal etc. handles it
and is necessary for environments where we can't run separate queue
daemons.
When the poorman-cron-ish thing is implemented, auto-renewal will work
for all users.
PuSH 0.4 spec:
https://pubsubhubbub.googlecode.com/git/pubsubhubbub-core-0.4.html
More on PuSH 0.4 release (incl. breaking changes):
https://groups.google.com/forum/#!msg/pubsubhubbub/7RPlYMds4RI/2mIHQTdV3aoJ
