BridgeLink owns a TcpClient to 127.0.0.1 and nothing else touches it. Emit() is
called from the Core thread; it enqueues onto a bounded drop-oldest queue and
returns. A link thread drains the queue and reconnects with backoff; a reader
thread parses inbound lines and marshals each to the Core thread via
Timer.DelayCall. An absent, slow, or wedged sidecar therefore cannot stall the
shard, which is the property the rest of the bridge depends on.
Outbound JSON is written by hand into a StringBuilder because it runs on the
Core thread for every event and the measured budget assumes that cost. Inbound
uses JavaScriptSerializer: commands arrive at human rates, so correctness beats
speed, and parsing happens off the Core thread anyway. That needs a
System.Web.Extensions reference.
server.hello is emitted per connection rather than once at ServerStarted. A
sidecar that restarts independently would otherwise never learn which shard it
is attached to. It carries a bootId, stable across reconnects and fresh on every
shard restart, so the sidecar can tell "I reconnected" from "the shard
restarted" and keep or discard its cache accordingly.
Two defects found by testing and fixed before commit:
- Backoff ceiling was 30s, so a sidecar restart cost up to half a minute of
buffering on a loopback socket. Now 5s.
- A stale reader could kill a fresh connection: reader.Join(1s) can time out,
and the old thread's finally block then set the shared _dead flag, possibly
tearing down the connection that had replaced it. Connections now carry an
epoch and a reader only marks dead the one it owned.
Acceptance evidence recorded in docs/PLAN.md §11: boots with no sidecar, buffers
through the outage and drains on connect, round-trips ping/pong on the Core
thread, survives unknown kinds and malformed JSON, and reconnects unattended.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
BridgeSeeder and BridgeProbe are not part of the bridge, but living under
overlay/Scripts/Custom/ meant deploy.ps1 would copy them onto any server we
deployed to. Move them to tools/scaffolding/, which nothing syncs.
overlay/Config/Bridge.cfg now carries the bridge's own settings (host, port,
queue cap, sweep intervals) rather than the scaffolding flags. Config.Get
returns false for a missing key, so a deployed server never runs the seeder or
probe even if their .cs files are present.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
