Instead of ignoring detached channels wehn replaying backlog,
process them as usual and relay messages as BouncerServ NOTICEs
if necessary. Advance the delivery receipts as if the channel was
attached.
Closes: https://todo.sr.ht/~emersion/soju/98
This allows to have shorter and more future-proof IDs. This also
guarantees the IDs will only use reasonable ASCII characters (no
spaces), removing the need to encode them for PING/PONG tokens.
TL;DR: supports for casemapping, now logs are saved in
casemapped/canonical/tolower form
(eg. in the #channel directory instead of #Channel... or something)
== What is casemapping? ==
see <https://modern.ircdocs.horse/#casemapping-parameter>
== Casemapping and multi-upstream ==
Since each upstream does not necessarily use the same casemapping, and
since casemappings cannot coexist [0],
1. soju must also update the database accordingly to upstreams'
casemapping, otherwise it will end up inconsistent,
2. soju must "normalize" entity names and expose only one casemapping
that is a subset of all supported casemappings (here, ascii).
[0] On some upstreams, "emersion[m]" and "emersion{m}" refer to the same
user (upstreams that advertise rfc1459 for example), while on others
(upstreams that advertise ascii) they don't.
Once upstream's casemapping is known (default to rfc1459), entity names
in map keys are made into casemapped form, for upstreamConn,
upstreamChannel and network.
downstreamConn advertises "CASEMAPPING=ascii", and always casemap map
keys with ascii.
Some functions require the caller to casemap their argument (to avoid
needless calls to casemapping functions).
== Message forwarding and casemapping ==
downstream message handling (joins and parts basically):
When relaying entity names from downstreams to upstreams, soju uses the
upstream casemapping, in order to not get in the way of the user. This
does not brings any issue, as long as soju replies with the ascii
casemapping in mind (solves point 1.).
marshalEntity/marshalUserPrefix:
When relaying entity names from upstreams with non-ascii casemappings,
soju *partially* casemap them: it only change the case of characters
which are not ascii letters. ASCII case is thus kept intact, while
special symbols like []{} are the same every time soju sends them to
downstreams (solves point 2.).
== Casemapping changes ==
Casemapping changes are not fully supported by this patch and will
result in loss of history. This is a limitation of the protocol and
should be solved by the RENAME spec.
... and do not forward INVITEs to downstreams that do not support the
capability.
The downstream capability can be permanent because there is no way for a
client to get the list of people invited to a channel, thus no state can
be corrupted.
... so that the JOIN/history batch takes into account all capabilities.
Without this commit for example, enabling multi-prefix after the batch
makes the client send NAMES requests for all channels, which generate
needless traffic.
This uses the fields added previously to the Channel struct to implement
the actual detaching/reattaching/relaying logic.
The `FilterDefault` values of the messages filters are currently
hardcoded.
The values of the message filters are not currently user-settable.
This introduces a new user event, eventChannelDetach, which stores an
upstreamConn (which might become invalid at the time of processing), and
a channel name, used for auto-detaching. Every time the channel detach
timer is refreshed (by receveing a message, etc.), a new timer is
created on the upstreamChannel, which will dispatch this event after the
duration (and discards the previous timer, if any).
This commit prevents downstream from sending those commands:
- NICK BouncerServ
- NICK BouncerServ/<network>
The later is necessary because soju would otherwise save the nick change
and, in the event that the downstream connects in single-upstream mode
to <network>, it will end up with the nickname "BouncerServ".
This patch implements basic message delivery receipts via PING and PONG.
When a PRIVMSG or NOTICE message is sent, a PING message with a token is
also sent. The history cursor isn't immediately advanced, instead the
bouncer will wait for a PONG message before doing so.
Self-messages trigger a PING for simplicity's sake. We can't immediately
advance the history cursor in this case, because a prior message might
still have an outstanding PING.
Future work may include optimizations such as removing the need to send
a PING after a self-message, or groupping multiple PING messages
together.
Closes: https://todo.sr.ht/~emersion/soju/11
TAGMSG are (in current specs and drafts from IRCv3) only used for
client tags. These are optional information by design (since they are
not distributed to all users), therefore it is preferable to discard
them accordingly to upstream, instead of waiting for all upstreams to
support the capability to advertise it.
Introduce a messageStore type, which will allow for multiple
implementations (e.g. in the DB or in-memory instead of on-disk).
The message store is per-user so that we don't need to deal with locking
and it's easier to implement per-user limits.
This simple implementation only advertises extended-join to downstreams
when all upstreams support it.
In the future, it could be modified so that soju buffers incoming
upstream JOINs, sends a WHO, waits for the reply, and sends an extended
join to the downstream; so that soju could advertise that capability
even when some or all upstreams do not support it. This is not the case
in this commit.
This panic happens when sending history to a multi-upstream client.
sendNetworkHistory is called on each network, but dc.network is nil.
Closes: https://todo.sr.ht/~emersion/soju/93
Instead, always read chat history from logs. Unify the implicit chat
history (pushing history to clients) and explicit chat history
(via the CHATHISTORY command).
Instead of keeping track of ring buffer cursors for each client, use
message IDs.
If necessary, the ring buffer could be re-introduced behind a
common MessageStore interface (could be useful when on-disk logs are
disabled).
References: https://todo.sr.ht/~emersion/soju/80
Keep the ring buffer alive even if all clients are connected. Keep the
ID of the latest delivered message even for online clients.
As-is, this is a net downgrade: memory usage increases because ring
buffers aren't free'd anymore. However upcoming commits will replace the
ring buffer with log files. This change makes reading from log files
easier.
