The readTimeout field (default 15s) was being applied via xnet.Pipe to both
directions of a bidirectional proxy connection. During asymmetric transfers
(e.g. HTTP file download), the direction reading from the tunnel sees no
data after the initial request is forwarded, causing SetReadDeadline to fire
after 15s and abort the entire transfer.
Fix: add a separate idleTimeout field (default 0=disabled) to the metadata
structs in both forward/local and forward/remote handlers, and switch
xnet.Pipe to use idleTimeout instead of readTimeout. The readTimeout field
now only applies to the initial protocol sniffing/handshake phase.
Also document readTimeout vs idleTimeout semantics across all 24 locations
in the x/ module where these timeouts appear:
- readTimeout: handshake sniffing deadline (handlers), upstream response
header timeout (http.Transport), or transport-level read deadline
- idleTimeout: idle read deadline per Pipe direction (0=disabled)
- ReadTimeout on Sniffer/SnifferBuilder: upstream response header/TLS
handshake read timeout during sniffing
Extract three pure-logic components from httpHandler to eliminate I/O
coupling from auth and sniffing construction, enabling synchronous unit
tests and reducing per-request allocation in sniffAndHandle:
- Authenticator struct with AuthResult return type — auth decisions no
longer write to the connection; callers handle response I/O. Auth
tests drop net.Pipe/goroutines for direct return-value assertions.
- SnifferBuilder pre-built in Init and reused per-connection via Build(),
replacing inline sniffing.Sniffer{} construction in sniffAndHandle.
- normalizeRequest extracted to util.go with NormalizedRequest type,
collapsing 20 lines of inline URL/normalisation into a single call.
- knockMatch extracted as standalone pure function.
- clampBodySize exported as ClampBodySize for cross-package use.
- util_test.go with 22 tests covering utility functions.
- helpers_test.go consolidates shared test fakes (logger, observer, conn).
ginuerzh