Eric Wong [Sat, 27 Jun 2020 10:03:42 +0000 (10:03 +0000)]
watch: stop importers before forking
This fixes cases where watch is handling both Maildirs and IMAP
connections. While we're at it, close open directories in the
IMAP children to save FDs.
Eric Wong [Sat, 27 Jun 2020 10:03:40 +0000 (10:03 +0000)]
watch: support IMAP polling
Not all IMAP servers support IDLE, and IDLE may be prohibitively
expensive for some IMAP servers with many inboxes. So allow
configuring a imap.$IMAP_URL.pollInterval=SECONDS to poll
mailboxes.
We'll also need to poll for NNTP servers in the future.
Eric Wong [Sat, 27 Jun 2020 10:03:39 +0000 (10:03 +0000)]
watch: wire up IMAP IDLE reapers to DS
We can avoid synchronous `waitpid(-1, 0)' and save a process
when simultaneously watching Maildirs.
One DS bug is fixed: ->Reset needs to clear the DS $in_loop flag
in forked children so dwaitpid() fails and allows git processes
to be reaped synchronously. TestCommon also calls DS->Reset
when spawning new processes, since t/imapd.t uses DS->EventLoop
while waiting on -watch to write.
Eric Wong [Sat, 27 Jun 2020 10:03:38 +0000 (10:03 +0000)]
ds: remove fields.pm usage
Since the removal of pseudo-hash support in Perl 5.10, the
"fields" module no longer provides the space or speed benefits
it did in 5.8. It also does not allow for compile-time checks,
only run-time checks.
To me, the extra developer overhead in maintaining "use fields"
args has become a hassle. None of our non-DS-related code uses
fields.pm, nor do any of our current dependencies. In fact,
Danga::Socket (which DS was originally forked from) and its
subclasses are the only fields.pm users I've ever encountered in
the wild. Removing fields may make our code more approachable
to other Perl hackers.
So stop using fields.pm and locked hashes, but continue to
document what fields do for non-trivial classes.
Eric Wong [Sat, 27 Jun 2020 10:03:37 +0000 (10:03 +0000)]
watch: use signalfd for Maildir watching
We can get rid of the janky wannabe
self-using-a-directory-instead-of-pipe thing we needed to
workaround Filesys::Notify::Simple being blocking.
For existing Maildir users, this should be more robust and
immune to missed wakeups for signalfd and kqueue-enabled
systems; as well as being immune to BOFHs clearing $TMPDIR
and preventing notifications from firing.
The IMAP IDLE code still uses normal Perl signals, so it's still
vulnerable to missed wakeups. That will be addressed in future
commits.
Eric Wong [Sat, 27 Jun 2020 10:03:35 +0000 (10:03 +0000)]
kqnotify|fake_inotify: detect Maildir write ops
We need to detect link(2) and rename(2) in other apps
writing to the Maildir.
We'll be removing the Filesys::Notify::Simple from -watch
in favor of using IO::KQueue or Linux::Inotify2 directly.
Ensure non-inotify emulations can support everything we
expect for Maildir writers.
Eric Wong [Sat, 27 Jun 2020 10:03:34 +0000 (10:03 +0000)]
watch: preliminary IMAP support
Only servers with IDLE are supported, for now. Polling will
be needed since users may need to watch many inboxes with
a few active connections due to IMAP server limitations.
Eric Wong [Sat, 27 Jun 2020 10:03:32 +0000 (10:03 +0000)]
watchmaildir: fix check for spam vs ham inbox conflicts
The old check was ineffective since we process the spam folder
config before ham inboxes; and would only fail when attempting
to treat the scalar "watchspam" string as an array ref.
Eric Wong [Sat, 27 Jun 2020 10:03:30 +0000 (10:03 +0000)]
imaptracker: use ~/.local/share/public-inbox/imap.sqlite3
Respect XDG_DATA_HOME to avoid cluttering ~/.public-inbox/.
Existing users of ~/.public-inbox/imap.sqlite3 will remain
supported, but the preference for new data is to use
~/.local/share and other paths standardized by XDG.
Apparently, using $1 from an octet string still results in a
multi-byte string. Thus we need to perform utf8::encode after
the regexp character match to ensure wide characters don't get
passed to encode_base64.
This fixes a bug in which caused -watch to crash when using
PublicInbox::Filter::SubjectTag to remove "[list prefix]"
tags from Subject: lines.
I only found this bug because the proposed -watch updates for
NNTP/IMAP support introduced a possible bug which triggered a
full rescan of old archives:
Eric Wong [Fri, 26 Jun 2020 23:26:18 +0000 (23:26 +0000)]
linkify: support imap, imaps, news, and snews URIs
Since we'll have an IMAP server released soon, maybe imaps://
and imap:// URLs can become popular.
news:// is defined with nntp:// in RFC 5538, and we can at least
support the news:// form in rendered HTML. snews:// may appear
in old mail archives, too, so we'll attempt to support it in
case clients do.
Eric Wong [Thu, 25 Jun 2020 10:09:36 +0000 (10:09 +0000)]
imap: always send EXISTS on uo2m_extend
Clients which are NOT in an IDLE state still need to be
notified of message existence. Unlike the EXPUNGE response,
untagged EXISTS responses seem to be allowed at any time
according to RFC 3501.
We'll also perform uo2m_extend on the NOOP command, since
NOOP is the recommended command for message polling.
Eric Wong [Tue, 23 Jun 2020 18:09:06 +0000 (18:09 +0000)]
ds: flush_write: early return on closed socket
This quiets warnings from IMAP::fetch_blob (called via
long_response) failing to access `$self->{ibx}->git'
because ->{ibx} gets deleted by IMAP::close.
Eric Wong [Tue, 23 Jun 2020 23:21:12 +0000 (23:21 +0000)]
git_async_cat: remove circular reference
While this circular reference was carefully managed to not leak
memory; it was still triggering a warning at -imapd/-nntpd
shutdown due to the EPOLL_CTL_DEL op failing after the $Epoll FD
gets closed.
So remove the circular reference by providing a ref to `undef',
instead.
Eric Wong [Wed, 24 Jun 2020 18:45:07 +0000 (18:45 +0000)]
lock: reduce inotify wakeups
We can reduce the amount of platform-specific code by always
relying on IN_MODIFY/NOTE_WRITE notifications from lock release.
This reduces the number of times our read-only daemons will
need to wake up when -watch sees no-op message changes
(e.g. replied, seen, recent flag changes).
Eric Wong [Tue, 23 Jun 2020 20:51:49 +0000 (20:51 +0000)]
testcommon: DS->Reset when using fork-only subprocess
This fixes a bug on FreeBSD 11 here -nntpd + TEST_RUN_MODE=2
(default) was occasionally causing failures in t/v2writable.t
due to the kqueue descriptor being auto-closed by the OS on fork.
Eric Wong [Sun, 21 Jun 2020 00:21:33 +0000 (00:21 +0000)]
init: add --skip-artnum parameter
For archivists with only newer mail archives, this option allows
reserving reserve NNTP article numbers for yet-to-be-archived
old messages. Indexers will need to be updated to support this
feature in future commits.
-V1 inboxes will now be initialized with SQLite and Xapian
support if this option is used, or if --indexlevel= is
specified.
Eric Wong [Sun, 21 Jun 2020 00:21:31 +0000 (00:21 +0000)]
init: add -j / --jobs parameter
On a powerful (by my standards) machine with 16GB RAM and an
7200 RPM HDD marketed for "enterprise" use, indexing a 8.1G (in
git) LKML snapshot from Sep 2019 did not finish after 7 days
with the default number (3) of Xapian shards (`--jobs=4') and
`--batch-size=10m'.
Indexing starts off fast, but progressively get slower as
contents of the inbox (including Xapian + SQLite DBs) could no
longer be cached by the kernel. Once the on-disk size
increased, HDD seek contention between the Xapian shard workers
slowed the process down to a crawl.
With a single shard, it still took around 3.5 days to index on
the HDD. That's not good, but it's far better than not
finishing after 7 days. So allow unfortunate HDD users to
easily specify a single shard on public-inbox-init.
For reference, a freshly TRIM-ed low-end TLC SSD on the SATA II
bus on the same machine indexes that same snapshot of LKML in
~7 hours with 3 shards and the same 10m batch size. In the past,
a higher-end consumer grade MLC SSDs on similar hardware indexed
a similarly sized-data set in ~4 hours.
Eric Wong [Tue, 16 Jun 2020 22:31:22 +0000 (22:31 +0000)]
nntp: support slow blob retrievals
Having `git cat-file' as a separate process naturally lends
itself to asynchronous dispatch. Our event loop for -nntpd no
longer blocks on slow git storage.
Pipelining in -imapd was tricky and bugs were exposed by
mbsync(1). Update t/nntpd.t to support pipelining ARTICLE
requests to ensure we don't have the same problems -imapd
did during development.
Eric Wong [Tue, 16 Jun 2020 22:31:21 +0000 (22:31 +0000)]
nntp: event_step: prepare for async git reads
This matches PublicInbox::IMAP::event_step and will allow us to
handle blob retrievals from git asynchronously without falling
over on pipelined requests.
Eric Wong [Tue, 16 Jun 2020 22:31:20 +0000 (22:31 +0000)]
daemon: use ->can to check for IO::Socket::SSL
Doing a ref($obj) string comparison ties us to IO::Socket::SSL
(and OpenSSL) In the future, we may support GnuTLS or other TLS
implementations. This was already done in the IMAP code.
Eric Wong [Tue, 16 Jun 2020 06:19:08 +0000 (06:19 +0000)]
imap: fix UID-offset-to-MSN mapping bugs
We need to clear the UID-offset-to-MSN mapping when
leaving mailboxes via EXAMINE/SELECT/CLOSE.
Furthermore, uo2m_last_uid() needs to account for tiny mailboxes
where the scalar representation of {uo2m} may be evaluated to
`false' in a boolean context.
Eric Wong [Tue, 16 Jun 2020 07:05:06 +0000 (07:05 +0000)]
imap: *SEARCH: reinstate "TEXT" search-key
I accidentally dropped "TEXT" handling while porting
the IMAP search query parser to Parse::RecDescent.
This reinstates it and adds a test to prevent future
regression, and the additional test fixes a counting
error for non-Xapian-enabled systems.
Eric Wong [Tue, 16 Jun 2020 05:05:40 +0000 (05:05 +0000)]
imap: *SEARCH: use Parse::RecDescent
For properly parsing IMAP search requests, it's easier to use a
recursive descent parser generator to deal with subqueries and
the "OR" statement.
Parse::RecDescent was chosen since it's mature, well-known,
widely available and already used by our optional dependencies:
Inline::C and Mail::IMAPClient. While it's possible to build
Xapian queries without using the Xapian string query parser;
this iteration of the IMAP parser still builds a string which is
passed to Xapian's query parser for ease-of-diagnostics.
Since this is a recursive descent parser dealing with untrusted
inputs, subqueries have a nesting limit of 10. I expect that is
more than adequate for real-world use.
Eric Wong [Tue, 16 Jun 2020 05:05:39 +0000 (05:05 +0000)]
imap: reinstate non-UID SEARCH
Since we support MSNs properly, now, it seems acceptable
to support regular SEARCH requests in case there are any
clients which still use non-UID SEARCH.
Eric Wong [Mon, 15 Jun 2020 09:17:28 +0000 (09:17 +0000)]
imap: stop_idle: fix parameter parsing :x
stop_idle was a noop when the client issues a "DONE"
continuation or just disconnects. This would not have
led to a long term memory leak since FDs get closed and
reused, anyways, and all of our InboxIdle mappings are
keyed by FD.
Eric Wong [Mon, 15 Jun 2020 07:43:17 +0000 (07:43 +0000)]
imap: improve IDLE handling at graceful shutdown
Since IMAP IDLE users aren't expected to issue any commands, we
can terminate their connections immediately on graceful
shutdown.
Furthermore, we need to drop the inotify FD from the epoll set
to avoid warnings during global destruction. Embarassingly,
this required fixing wacky test ordering from 2a717d13f10fcdc6
("nntpd+imapd: detect replaced over.sqlite3")
Eric Wong [Sat, 13 Jun 2020 20:27:04 +0000 (20:27 +0000)]
t/imapd: quiet overload warning from Mail::IMAPClient
Mail::IMAPClient understandably stumbles into a warning
by our bogus test request. Just silence it on our end
since it's not normal operation for Mail::IMAPClient.
Eric Wong [Sun, 14 Jun 2020 00:25:04 +0000 (00:25 +0000)]
inboxidle: support Linux::Inotify2 1.x
Linux::Inotify2 1.x lacked ->on_overflow and ->broadcast
methods. Just don't use them for now. We may eventually
provide a pure Perl alternative which doesn't require closures,
XS, or the common::sense dependency.
Overflowing the inotify queue seems difficult to trigger at
the moment: /proc/sys/fs/inotify/max_queued_events defaults
to 16384 on a my CentOS 7.x VM with 2GB RAM.
Eric Wong [Sun, 14 Jun 2020 00:25:03 +0000 (00:25 +0000)]
testcommon: allow OR-ing module dependencies
IMAP requires either the Email::Address::XS or Mail::Address
package (part of perl-MailTools RPM or libmailtools-perl deb);
and Email::Address::XS is not officially packaged for some older
distros, most notably CentOS 7.x.
Eric Wong [Thu, 11 Jun 2020 00:57:53 +0000 (00:57 +0000)]
nntpd+imapd: detect replaced over.sqlite3
For v1 inboxes (and possibly v2 in the future, for VACUUM),
public-inbox-compact replaces over.sqlite3 with a new file.
This currently doesn't need an extra inotify watch descriptor
(or FD for kevent) at the moment, so it can coexist nicely for
systems w/o IO::KQueue or Linux::Inotify2.
Eric Wong [Fri, 12 Jun 2020 23:49:24 +0000 (23:49 +0000)]
imap: introduce memory-efficient uo2m mapping
Since we limit our mailboxes slices to 50K and can guarantee a
contiguous UID space for those mailboxes, we can store a mapping
of "UID offsets" (not full UIDs) to Message Sequence Numbers as
an array of 16-bit unsigned integers in a 100K scalar.
For UID-only FETCH responses, we can momentarily unpack the
compact 100K representation to a ~1.6M Perl array of IV/UV
elements for a slight speedup.
Furthermore, we can (ab)use hash key deduplication in Perl5 to
deduplicate this 100K scalar across all clients with the same
mailbox slice open.
Technically we can increase our slice size to 64K w/o increasing
our storage overhead, but I suspect humans are more accustomed
to slices easily divisible by 10.
Eric Wong [Wed, 10 Jun 2020 07:05:19 +0000 (07:05 +0000)]
imap: FETCH: proper MSN => UID mapping for requests
This finally seems to make mutt header caching behave properly.
We expect to be able to safely load 50K IV/UVs in memory without
OOM, since that's "only" 1.6 MB that won't live beyond a single
event loop iteration. So create a simple array which can
quickly map MSNs in requests to UIDs and not leave out messages.
MSNs in the FETCH response will NOT be correct, since it's
inefficient to implement properly and mutt doesn't seem to
care.
Since the conversion code is easily shared, "UID SEARCH" can
allow the same MSN => UID mapping non-UID "FETCH" does.
Eric Wong [Wed, 10 Jun 2020 07:05:18 +0000 (07:05 +0000)]
over: uid_range: remove LIMIT
The IMAP code already limits the range to UID_SLICE (50K),
so that's about 1.6MB of of IVs for an ephemeral allocation
that won't live beyond one iteration of the event loop.
Eric Wong [Wed, 10 Jun 2020 07:05:17 +0000 (07:05 +0000)]
imap: remove non-UID SEARCH for now
Supporting MSNs in long-lived connections beyond the lifetime of
a single request/response cycle is not scalable to a C10K
scenario. It's probably not needed, since most clients seem to
use UIDs.
A somewhat efficient implementation I can come up uses
pack("S*" ...) (AKA "uint16_t mapping[50000]") has an overhead
of 100K per-client socket on a mailbox with 50K messages. The
100K is a contiguous scalar, so it could be swapped out for
idle clients on most architectures if THP is disabled.
An alternative could be to use a tempfile as an allocator
partitioned into 100K chunks (or SQLite); but I'll only do that
if somebody presents a compelling case to support MSN SEARCH.
Eric Wong [Wed, 10 Jun 2020 07:05:15 +0000 (07:05 +0000)]
imap: misc cleanups and notes
Note some of our limitations for potential hackers.
We'll be renaming "UID_BLOCK" to "UID_SLICE", since "block" is
overused term and "slice" isn't used in our codebase. Also,
document how "slice" and "epochs" are similar concepts for
different clients.
Eric Wong [Wed, 10 Jun 2020 07:05:12 +0000 (07:05 +0000)]
imap: STATUS/EXAMINE: rely on SQLite overview
We can get exact values for EXISTS, UIDNEXT using SQLite
rather than calculating off $ibx->mm->max ourselves.
Furthermore, $ibx->mm is less useful than $ibx->over for IMAP
(and for our read-only daemons in general) so do not depend on
$ibx->mm outside of startup/reload to save FDs and reduce kernel
page cache footprint.
Eric Wong [Wed, 10 Jun 2020 07:05:11 +0000 (07:05 +0000)]
imap: FETCH: try to make fake MSNs sequentially
This appears to significantly improve header caching behavior
with mutt. With the current public-inbox.org/git mirror(*),
mutt will only re-FETCH the last ~300 or so messages in the
final "inbox.comp.version-control.git.7" mailbox, instead of
~49,000 messages every time.
It's not perfect, but a 500ms query is better than a >10s query
and mutt itself spends as much time loading its header cache.
(*) there are many gaps in NNTP article numbers (UIDs) due to
spam removal from public-inbox-learn.
Eric Wong [Wed, 10 Jun 2020 07:05:10 +0000 (07:05 +0000)]
imap: further speed up HEADER.FIELDS FETCH requests
Since headers are big and include a lot of lines MUAs don't
care about, we can skip the CRLF_HDR ops and just do the
CRLF conversion in partial_hdr_get and partial_hdr_not.
This is another 10-15% speedup for mutt w/o header caching.
Eric Wong [Wed, 10 Jun 2020 07:05:09 +0000 (07:05 +0000)]
imap: FETCH: more granular CRLF conversion
This speeds up requests from mutt for HEADER.FIELDS by around 10%
since we don't waste time doing CRLF conversion on large message
bodies that get discarded, anyways.
Eric Wong [Wed, 10 Jun 2020 07:05:08 +0000 (07:05 +0000)]
imap: cleanup ->{uid_base} usage
Ensure {uid_base} is always set, so we don't need to add `//'
checks everywhere. Furthermore, this fixes a hard-to-test bug
where the STATUS command would inadvertantly clobber {uid_base}.
Eric Wong [Wed, 10 Jun 2020 07:05:07 +0000 (07:05 +0000)]
imap: reinstate some message sequence number support
The performance problem with mutt not using header caches isn't
fixed, yet, but mutt header caching seems to depend on MSNs
(message sequence numbers). We'll switch to storing the 0-based
{uid_base} instead of the 1-based {uid_min} since it simplifies
most of our code.
Eric Wong [Wed, 10 Jun 2020 07:05:06 +0000 (07:05 +0000)]
imap: support 8000 octet lines
RFC 2683 section 3.2.1.5 recommends it:
> For its part, a server should allow for a command line of at least
> 8000 octets. This provides plenty of leeway for accepting reasonable
> length commands from clients. The server should send a BAD response
> to a command that does not end within the server's maximum accepted
> command length.
To conserve memory, we won't bother reading the entire line
before sending the BAD response and disconnecting them.
Eric Wong [Wed, 10 Jun 2020 07:05:05 +0000 (07:05 +0000)]
imap: LIST shows "INBOX" in all caps
While selecting a mailbox is done case-insensitively, "INBOX" is
special for the LIST command, according to RFC 3501 6.3.8:
> The special name INBOX is included in the output from LIST, if
> INBOX is supported by this server for this user and if the
> uppercase string "INBOX" matches the interpreted reference and
> mailbox name arguments with wildcards as described above. The
> criteria for omitting INBOX is whether SELECT INBOX will
> return failure; it is not relevant whether the user's real
> INBOX resides on this or some other server.
Thus, the existing news.public-inbox.org convention of naming
newsgroups starting with "inbox." needs to be special-cased to
not confuse clients.
While we're at it, do not create ".0" for dummy newsgroups if
they're selected, either.
Eric Wong [Wed, 10 Jun 2020 07:05:03 +0000 (07:05 +0000)]
imap: rely on smsg->{bytes} for RFC822.SIZE
Since we started indexing the CRLF-adjusted size of messages,
we can take an order-of-magnitude speedup for certain MUAs
which fetch this attribute without needing much else.
Admins are encouraged to --reindex existing inboxes for IMAP
support, anyways. It won't be fatal if it's not reindexed, but
some client bugs and warnings can be fixed and they'll be able
to support more of IMAP.
Eric Wong [Wed, 10 Jun 2020 07:05:02 +0000 (07:05 +0000)]
index: account for CRLF conversion when storing bytes
NNTP and IMAP both require CRLF conversions on the wire.
They're also the only components which care about
$smsg->{bytes}, so store the CRLF-adjusted value in over.sqlite3
and Xapian DBs..
This will allow us to optimize RFC822.SIZE fetch item in IMAP
without triggering size mismatch errors in some clients' default
configurations (e.g. Mail::IMAPClient), but not most others.
It could also fix hypothetical problems with NNTP clients that
report discrepancies between overview and article data.
Eric Wong [Wed, 10 Jun 2020 07:05:01 +0000 (07:05 +0000)]
searchidx: v1 (re)-index uses git asynchronously
We can cleanup some of our v1 code slightly and let git do
I/O+decoding in parallel. This gives a slight 2-4%
re-indexing performance boost even on an SSD.
Eric Wong [Wed, 10 Jun 2020 07:05:00 +0000 (07:05 +0000)]
imap: split ->logged_in attribute into a separate class
This is one boolean attribute not worth wasting space for.
With 20000 sockets, this reduces RSS by around 5% at a glance,
and locked hashes doesn't do us much good when clients
use compression, anyways.
Eric Wong [Wed, 10 Jun 2020 07:04:59 +0000 (07:04 +0000)]
imap: 30 minute auto-logout timer
RFC 3501 section 5.4 requires this to be >= 30 minutes,
10x higher than what is recommended for NNTP. Fortunately
our design is reasonably memory-efficient despite being Perl.
Eric Wong [Wed, 10 Jun 2020 07:04:58 +0000 (07:04 +0000)]
imap: IDLE: avoid extraneous wakeups, keep-alive
We should not waste memory for IDLE unless it's used on the most
recent inbox slice. We also need to keep the IDLE connection
alive regardless of $PublicInbox::DS::EXPTIME.
Eric Wong [Wed, 10 Jun 2020 07:04:56 +0000 (07:04 +0000)]
imap: UID FETCH: optimize for smsg-only case
We can avoid loading the entire message from git when mutt makes
a "UID FETCH" request for "(UID FLAGS)". This speeds mutt up by
more than an order-of-magnitude in informal measurements.
Eric Wong [Wed, 10 Jun 2020 07:04:55 +0000 (07:04 +0000)]
imap: compile UID FETCH to opcodes
This is just a hair faster and cacheable in the future, if we
need it. Most notably, this avoids doing PublicInbox::Eml->new
for simple "RFC822", "BODY[]", and "RFC822.SIZE" requests.
Eric Wong [Wed, 10 Jun 2020 07:04:54 +0000 (07:04 +0000)]
imap: remove dummies from sequence number FETCH
Dummy messages make for bad user experience with MUAs which
still use sequence numbers. Not being able to fetch a message
doesn't seem fatal in mutt, so just ignore (sometimes large)
gaps.
Eric Wong [Wed, 10 Jun 2020 07:04:52 +0000 (07:04 +0000)]
search: index byte size of a message for IMAP search
Searching for messages smaller than a certain size is allowed by
offlineimap(1), mbsync(1), and possibly other tools. Maybe
public-inbox-watch will support it, too.
I don't see a reason to expose searching by size via WWW search
right now (but maybe in the future, I could be convinced to).
Note: we only store the byte-size of the message in git,
this is typically LF-only and we won't have the correct
size after CRLF conversion for NNTP or IMAP.
Eric Wong [Wed, 10 Jun 2020 07:04:51 +0000 (07:04 +0000)]
over: get_art: use dbh->prepare_cached
This speeds up xt/imapd-validate.t by around 10% when used with
an abandoned patch to remove ->query_xover. We may also depend
on this further if we abandon storing doc_data in Xapian to save
disk space.
Eric Wong [Wed, 10 Jun 2020 07:04:46 +0000 (07:04 +0000)]
imap: EXAMINE/STATUS: return correct counts
We can share code between them and account for each 50K
mailbox slice. However, we must overreport these for
non-zero slices and just return lots of empty data for
high-numbered slices because some MUAs still insist
on non-UID fetches.
Eric Wong [Wed, 10 Jun 2020 07:04:42 +0000 (07:04 +0000)]
imap: omit $UID_END from mailbox name, use index
Having two large numbers separated by a dash can make visual
comparisons difficult when numbers are in the 3,000,000 range
for LKML. So avoid the $UID_END value, since it can be
calculated from $UID_MIN. And we can avoid large values of
$UID_MIN, too, by instead storing the block index and just
multiplying it by 50000 (and adding 1) on the server side.
Of course, LKML still goes up to 72, at the moment.
Eric Wong [Wed, 10 Jun 2020 07:04:41 +0000 (07:04 +0000)]
imapd: ensure LIST is sorted alphabetically, for now
I'm not sure this matters, and it could be a waste of
CPU cycles if no real clients care. However, it does
make debugging over telnet or s_client a bit easier.
Eric Wong [Wed, 10 Jun 2020 07:04:40 +0000 (07:04 +0000)]
imap: require ".$UID_MIN-$UID_END" suffix
Finish up the IMAP-only portion of iterative config reloading,
which allows us to create all sub-ranges of an inbox up front.
The InboxIdler still uses ->each_inbox which will struggle with
100K inboxes.
Having messages in the top-level newsgroup name of an inbox will
still waste bandwidth for clients which want to do full syncs
once there's a rollover to a new 50K range. So instead, make
every inbox accessible exclusively via 50K slices in the form of
"$NEWSGROUP.$UID_MIN-$UID_END".
This introduces the DummyInbox, which makes $NEWSGROUP
and every parent component a selectable, empty inbox.
This aids navigation with mutt and possibly other MUAs.
Finally, the xt/perf-imap-list maintainer test is broken, now,
so remove it. The grep perlfunc is already proven effective,
and we'll have separate tests for mocking out ~100k inboxes.
Eric Wong [Wed, 10 Jun 2020 07:04:38 +0000 (07:04 +0000)]
imap: break giant inboxes into sub-inboxes of 50K messages
This limit on mailbox size should keep users of tools like
mbsync (isync) and offlineimap happy, since typical filesystems
struggle with giant Maildirs.
I chose 50K since it's a bit more than what LKML typically sees
in a month and still manages to give acceptable performance on
my ancient Centrino laptop.
There were also no responses to my original proposal at:
<https://public-inbox.org/meta/20200519090000.GA24273@dcvr/>
so no objections, either :>
Eric Wong [Wed, 10 Jun 2020 07:04:37 +0000 (07:04 +0000)]
imap: case-insensitive mailbox name comparisons
IMAP RFC 3501 stipulates case-insensitive comparisons, and so
does RFC 977 (NNTP). However, INN (nnrpd) uses case-sensitive
comparisons, so we've always used case-sensitive comparisons for
NNTP to match nnrpd behavior.
Unfortunately, some IMAP clients insist on sending "INBOX" with
caps, which causes problems for us. Since NNTP group names are
typically all lowercase anyways, just force all comparisons to
lowercase for IMAP and warn admins if uppercase-containing
newsgroups won't be accessible over IMAP.
This ensures our existing -nntpd behavior remains unchanged
while being compatible with the expectations of real-world IMAP
clients.
Eric Wong [Wed, 10 Jun 2020 07:04:34 +0000 (07:04 +0000)]
xt: add imapd-validate and imapd-mbsync-oimap
imapd-validate is a beefed up version of our nntpd-validate test
which hammers the server with parallel connections over regular
IMAP, IMAPS, IMAP+STARTTLS; and COMPRESS=DEFLATE variants of
each of those. It uses $START_UID:$END_UID fetch ranges to
reduce requests and slurp many responses at once to saturate
"git cat-file --batch" processes.
mbsync(1) also uses pipelining extensively (but IMHO
unnecessarily), so it was able to shake out some bugs in
the async git code.
Finally, we remove xt/cmp-imapd-compress.t since it's
redundant now that we have PublicInbox::IMAPClient to work
around bugs in Mail::IMAPClient.
Eric Wong [Wed, 10 Jun 2020 07:04:33 +0000 (07:04 +0000)]
imapclient: wrapper for Mail::IMAPClient
We'll be using this wrapper class to workaround some upstream
bugs in Mail::IMAPClient. There may also be experiments with
new APIs for more performance.
Eric Wong [Wed, 10 Jun 2020 07:04:32 +0000 (07:04 +0000)]
git: async: automatic retry on alternates change
This matches the behavior of the existing synchronous ->cat_file
method. In fact, ->cat_file now becomes a small wrapper around
the ->cat_async method.