Adds the client's first outbound call: GET {server}/api/config, carrying
X-ThoughtSync-Client and X-ThoughtSync-Protocol, feeding compat::evaluate.
Deliberately its OWN commit. This introduces the first HTTP+TLS stack into a
crate that cross-compiles to Windows from Linux via cargo-xwin — the lane
that has already broken once on a transitive C dependency (libsqlite3-sys
needing llvm-lib). Landing it alone means a failure here has exactly one
possible cause, instead of surfacing mid-way through M10.7's much larger
change where it would be expensive to bisect.
TLS backend is native-tls, NOT rustls, and that is the whole point of the
choice: on x86_64-pc-windows-msvc native-tls resolves to `schannel`, which
is pure-Rust bindings to the OS TLS stack, so nothing C or assembly has to
cross-compile on the fragile lane. rustls would pull in ring/aws-lc-rs and
their assembler. On Linux native-tls uses OpenSSL, whose headers ci-tauri
already ships (libssl-dev, part of Tauri's own Linux prerequisites).
Verified from run 2884's log rather than assumed: tokio and http are already
in the Windows tree via tauri, but no HTTP client and no TLS stack were —
so this genuinely is new surface there, not a no-op.
probe() distinguishes "never got a usable answer" (Err) from "answered, but
we can't work with it" (Ok + verdict). Those need very different messages:
one is "check what you typed", the other is "update something". Transport
errors are translated out of reqwest's Display, which is accurate but reads
like a stack trace.
Still no UI — M10.7 owns the link/settings surface that calls server_probe.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SreJkbxB4gx8pPsu8QbLPi
Version the sync WIRE PROTOCOL separately from either program's release
version, so a self-hosted server and the desktop app can sit on different
releases and still work out whether they can talk.
Each side declares two numbers — what it speaks, and the oldest counterpart
it accepts. Either side can therefore mark a change breaking without the
other shipping in step, which is the whole point: no app↔server lockstep.
Server advertises on the existing public /api/config (a client must be able
to ask "can I talk to you?" before it holds a device token, or even has an
account): sync_protocol_version, min_client_protocol_version, sync_features.
sync_features exists because a version number can only say newer/older. An
ADDITIVE change earns a capability name instead of a minimum bump, so a
newer client meeting an older server drops that one feature and syncs the
rest, rather than refusing. Raising a minimum is reserved for genuinely
breaking changes — it's the switch that hard-blocks the other side.
Client half is pure decision logic (sync/compat.rs), no I/O, so every branch
is unit-testable — there's no live-server lane in CI. Three outcomes: ok /
degraded{unavailable} / incompatible{reason, client_must_update}. The last
names which side can fix it, so the message is actionable. A server that
predates the handshake sends no protocol fields at all; that reads as
"update the server", deliberately not as a parse error, which would look to
the user like they mistyped the URL.
normalize_base_url defaults a bare host to https://, never http:// —
silently downgrading would put a long-lived device token on the wire in
cleartext because someone omitted five characters. Plain HTTP on a trusted
LAN stays supported; the user types http:// and thereby chooses it.
Transport (the actual fetch) lands next, separately: it needs an HTTP/TLS
stack, and that's a real risk to the Windows cross-compile lane, so it gets
its own CI run to bisect against rather than riding along with this.
No UI here by design — the link/settings surface it feeds is M10.7's, per
this task's own sequencing.
Policy documented in docs/sync.md.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SreJkbxB4gx8pPsu8QbLPi