Record the execution platform (kind vk|telegram|direct + device subtype
ios|android|web) on each session, captured at creation and carried
gateway->backend as a trusted X-Platform header, so the upcoming
store-compliance gate has an unforgeable execution context.
- backend.sessions gains nullable platform_kind/platform_subtype columns
(migration 00011, CHECK-constrained, jet regenerated); session.Platform
captures them at mint, resolve returns them, middleware exposes platform(c).
kind is derived from the establish endpoint, never a client field; the
account-merge session mint inherits the caller's platform.
- gateway derives the platform (VK subtype from the signed vk_platform via
vkauth, Telegram/direct best-effort from the client) and injects X-Platform
on every authenticated backend call through the request context.
- ui submits a best-effort device subtype on the telegram/guest/email login
requests (new FBS subtype field); VK is server-derived from the signed params.
- an unattributed session is untrusted (view-only); VK/TG self-heal on the next
cold-start re-mint, direct/email on re-login.
Signal plumbing only, no user-visible change; X-Platform is inert until the
gate consumes it.
A browser has no signed VK Mini App launch params, so linking VK on the web uses
VK ID's raw OAuth 2.1 flow (PKCE, no @vkid/sdk): the SPA redirects to VK's hosted
login and returns with an authorization code, which the gateway exchanges
server-side (confidential, under the VK "Web" app's protected key) for the trusted
vk user id — then the existing link/merge machinery attaches or merges it.
- fbs LinkVKRequest{code, device_id, code_verifier}; codec + TS bindings.
- backend link.Service ConfirmVK/MergeVK/attachVK (KindVK, mirror Telegram),
handleLinkVK[Merge], routes /user/link/vk[/merge], backendclient LinkVK[Merge].
- gateway internal/vkid confidential code exchange (id.vk.com/oauth2/auth);
transcode link.vk.confirm/merge (registered only when configured) + config
GATEWAY_VK_ID_{APP_ID,CLIENT_SECRET,REDIRECT_URL} + main wiring.
- UI lib/vkid (PKCE authorize redirect + callback), Profile "Link VK" control,
boot callback handling; a merge re-authorizes for a fresh code (VK codes are
single-use). Web-only (a redirect strands a Mini App webview).
- Deploy: VITE_VK_APP_ID + VITE_VK_ID_REDIRECT_URL build args + gateway env,
ci.yaml/prod-deploy TEST_/PROD_ vars, compose/Dockerfile/.env.example/README.
- Tests: vkid exchange unit (string/number user_id, id_token fallback, errors),
transcode link.vk, backend ConfirmVK/MergeVK inttest, codec encodeLinkVK.
- Docs: ARCHITECTURE §4, FUNCTIONAL(+ru), gateway README.