Make /capabilities fail-closed and add the admin features surface.
- Secret-presence downgrade (§4.2): a chain whose flag is on but whose source is
unconfigured (btc/ltc no electrum URL, xmr/wow no LWS admin key, grin no owner
secret) now reports enabled:false — so /capabilities never advertises a chain
that would 404, and a missing-secret downgrade is indistinguishable from a
deliberately-off chain. grin_relay requires serviceable Grin; nostr_identity
requires PUBLIC_API_URL. effective_capabilities() is the single explicit mapper.
- contract_version stamp on the public document (clients soft-notice a higher
value, ignore unknown additive keys).
- GET /admin/features (admin_guard): the resolved effective state PLUS admin-only
downgrade reasons (the public surface hides the reason, per §4.3).
- Golden test: the public capabilities JSON, built from a fully-secret-seeded
config, contains no secret value (asserts no "integration-test-" substring).
openapi regenerated (contract_version). Admin features view stays off the public
OpenAPI.
Deferred (documented): runtime mutation — PUT /admin/features + a DB feature-
override table + resolve() precedence + Arc hot-swap + CLI `features set`. Flags
are env/config-driven for v1; runtime tuning (and its fleet propagation, itself a
deferred LB decision) is a later addition.
From a multi-lens adversarial review of the capabilities + prices work:
- PRICES_ASSETS="" now means NONE, not all (real bug): from_env used env_opt,
which collapses unset and present-but-empty into None, so the documented
"empty = none" silently served all five feeds. Read via env::var so unset =>
all, present (even empty) => the listed subset or none.
- PRICES_CURRENCY is now validated against a curated SUPPORTED_PRICE_CURRENCIES
allowlist. Previously a typo (e.g. "usdd") booted, advertised prices:true, and
served an empty feed forever (the provider returns empty quotes for an unknown
currency) — a fail-open path inconsistent with the adjacent provider/asset
checks.
- PRICES_PROVIDER is lowercased at read, matching the asset/currency
normalization (mixed-case no longer trips the allowlist).
- validate() now requires an Electrum URL for an enabled BTC/LTC chain (hard
error in prod, warn in dev), symmetric with the xmr/wow/grin secret checks.
Keeps /capabilities honest: a chain it can't serve won't boot advertising
itself as available.
Tests: config regressions (currency, utxo-electrum); a PriceClient feed-subset
selection unit test; the /prices integration test now populates the snapshot and
asserts the served quotes + RFC-3339 timestamp (the prior PRICES_ASSETS env-var
was inert under the harness); capabilities asserts network presence/null across
all five chains.
Dismissed after verification: coingecko json() was already switched to a
streaming read_capped; fleet refresh-jitter (no API key, single-node,
self-healing on 429); prices capability staying a bare bool (/prices carries the
currency + per-asset map).
Public, unauthenticated description of what this deployment offers, so the
wallet can adapt to the instance it's pointed at — grey out disabled chains and
features, and pick the right network. This is the client-facing half of the
open-core/feature-flag design: every capability is a config switch, surfaced
here. No secrets — only on/off flags and public network names.
Response: { version, chains: { btc/ltc/xmr/wow/grin: { enabled, network } },
features: { grin_relay, prices, nostr_identity, tips } }. UTXO chains carry
their configured network; CryptoNote/Grin report null. On the normal rate-limit
tier. Registered in openapi (system tag); 1 L1 test (public, well-shaped).
jwinterm