This adds support for upstream echo-message. This capability is
enabled when the upstream supports labeled-response.
When it is enabled, we don't echo downstream messages in the downstream
handler, but rather wait for the upstream to echo it, to produce it to
downstreams.
When it is disabled, we keep the same behaviour as before: produce the
message to all downstreams as soon as it is received from the
downstream.
In other words, the main functional difference is that when the upstream
supports labeled-response, the client will now receive an echo for its
messages when the server acknowledges them, rather than when soju acks
them.
Additionally, uc.produce was refactored to take an ID rather than a
downstream.
This avoids having more than one in flight at a time (avoids
hitting rate limits a bit) and routes back replies to the correct
downstream connection (even if labeled-response isn't supported).
Closes: https://todo.sr.ht/~emersion/soju/193
Per the spec:
> If the source is missing from a message, it’s is assumed to have originated
> from the client/server on the other end of the connection the message was
> received on.
READ lets downstream clients share information between each other about
what messages have been read by other downstreams.
Each target/entity has an optional corresponding read receipt, which is
stored as a timestamp.
- When a downstream sends:
READ #chan timestamp=2020-01-01T01:23:45.000Z
the read receipt for that target is set to that date
- soju sends READ to downstreams:
- on JOIN, if the client uses the soju.im/read capability
- when the read receipt timestamp is set by any downstream
The read receipt date is clamped by the previous receipt date and the
current time.
If the nickname we want is taken, fallback to another one by
appending underscores. Use MONITOR to figure out when we can request
our desired nick again.
Closes: https://todo.sr.ht/~emersion/soju/35
If a client queues a high number of commands and then disconnects,
remove all of the pending commands. This avoids unnecessarily
sending commands whose results won't be used.
Once the downstream connection has logged in with their bouncer
credentials, allow them to issue more SASL auths which will be
redirected to the upstream network. This allows downstream clients
to provide UIs to login to transparently login to upstream networks.
Add support for MONITOR in single-upstream mode.
Each downstream has its own set of monitored targets. These sets
are merged together to compute the MONITOR commands to send to
upstream.
Each upstream has a set of monitored targets accepted by the server
alongside with their status (online/offline). This is used to
directly send replies to downstreams adding a target another
downstream has already added, and send MONITOR S[TATUS] replies.
Co-authored-by: delthas <delthas@dille.cc>
This has the following upsides:
- We can now routes WHO replies to the correct client, without
broadcasting them to everybody.
- We are less likely to hit server rate limits when multiple downstreams
are issuing WHO commands at the same time.
