Wire up the config parsing infrastructure into the server:
- NatsServer: add ReloadConfig() with digest-based change detection,
diff/validate, CLI override preservation, and side-effect triggers
- Program.cs: two-pass CLI parsing — load config file first, then
apply CLI args on top with InCmdLine tracking for reload precedence
- SIGHUP handler upgraded from stub warning to actual reload
- Remove config file "not yet supported" warning from StartAsync
- Add integration tests for config loading, CLI overrides, and
reload validation
Port of Go server/reload.go option interface and diffing logic. Compares
NatsOptions property-by-property to detect changes, tags each with category
flags (logging, auth, TLS, non-reloadable), validates that non-reloadable
options (Host, Port, ServerName) are not changed at runtime, and provides
MergeCliOverrides to ensure CLI flags always take precedence over config
file values during hot reload.
- Add MaxIncludeDepth = 10 constant and thread _includeDepth through ParserState
constructors, ProcessInclude, ParseFile (private overload), and ParseEnvValue
to prevent StackOverflowException from recursive includes
- Fix PopContext to check _ctxs.Count <= 1 instead of == 0 so the root context
is never popped, replacing silent crash with clear InvalidOperationException
- Add else throw in SetValue so unknown context types surface as bugs rather
than silently dropping values
Implements NatsConfParser with Parse, ParseFile, and ParseFileWithDigest
methods. Supports nested maps/arrays, variable resolution with block
scoping and environment fallback, bcrypt password literals, integer
suffix multipliers, include directives, and cycle detection.
Adds 10 new fields to NatsOptions (ClientAdvertise, TraceVerbose, MaxTracedMsgLen,
DisableSublistCache, ConnectErrorReports, ReconnectErrorReports, NoHeaderSupport,
MaxClosedClients, NoSystemAccount, SystemAccount) plus InCmdLine tracking set.
Moves MaxClosedClients from a private constant in NatsServer to a configurable option.
Port the NATS configuration file lexer from Go's conf/lex.go to C#.
The lexer is a state-machine tokenizer that supports the NATS config
format: key-value pairs with =, :, or whitespace separators; nested
maps {}; arrays []; single and double quoted strings with escape
sequences; block strings (); variables $VAR; include directives;
comments (# and //); booleans; integers with size suffixes (kb, mb, gb);
floats; ISO8601 datetimes; and IP addresses.
Avoids re-serializing the same ServerInfo JSON on every new connection. The
cache is rebuilt when the ephemeral port is resolved. Connections that carry a
per-connection nonce (NKey auth) continue to serialize individually so the nonce
is included correctly.
Reconcile close reason tracking: feature branch's MarkClosed() and
ShouldSkipFlush/FlushAndCloseAsync now use main's ClientClosedReason
enum. ClosedState enum retained for forward compatibility.
Reject connections that send no_responders:true without headers:true,
since the 503 HMSG response requires header support. Add three tests:
connection rejection, acceptance with headers, and 503 delivery flow.
When a client sends CONNECT {"verbose":true}, the server now responds
with +OK\r\n after successfully processing CONNECT, PING, SUB, UNSUB,
and PUB/HPUB commands, matching the Go NATS server behavior.
Accumulate InMsgs/InBytes locally per ReadAsync cycle and flush once,
reducing from 4 Interlocked operations per published message to 2 per
read cycle. This matches the Go server's approach of batching stats.
When a PUB with a reply-to subject has no matching subscribers and the
sender opted into no_responders, send a 503 HMSG back on the reply
subject so request-reply callers can fail fast instead of timing out.
