Module protocol 

Pure protocol logic — signed-payload builders, freshness check, turn rotation, replay dedup. Mirrors the non-DB parts of parley/services/{rooms,messages,participants,dedup}.py.

Structs

DedupStore

In-memory replay-detection store. Single-process only; SPEC §10.2 notes that a multi-worker deployment needs a shared backing store.

Constants

CLOCK_SKEW_SECS

SPEC §6.6: created_at must be within ±60 s of server now.

MAX_BODY_BYTES

SPEC C9: message body max bytes.

MAX_TURNS_MAX

SPEC C6: maximum allowed max_turns.

MAX_TURNS_MIN

SPEC C6: minimum allowed max_turns.

TOPIC_MAX_CHARS

SPEC C5: room topic maximum character count.

TOPIC_MIN_CHARS

SPEC C5: room topic minimum character count.

TTL_HOURS_MAX

Maximum allowed ttl_hours on room creation.

TTL_HOURS_MIN

Minimum allowed ttl_hours on room creation.

Statics

DEFAULT_DEDUP

Shared default dedup store, mirroring the module-level _store in parley/services/dedup.py. Most embedders will prefer an owned DedupStore instance — this exists for parity with the reference impl.

Functions

accept_payload

Build the canonical signed bytes for POST /v1/rooms/{id}/accept (C13). Sorted keys: agent_pubkey, created_at, room_id.

check_freshness

Same, against the system clock.

check_post_message

Returns Ok iff every precondition for a post_message write passes. Order matches SPEC §6.6. Caller passes the relevant room/participant state extracted from their own store.

close_payload

Build the canonical signed bytes for POST /v1/rooms/{id}/close (C14). Sorted keys: created_at, room_id, summary. summary of None is emitted as literal JSON null.

create_room_payload

Build the canonical signed bytes for POST /v1/rooms (C11). Sorted keys: created_at, invite_pubkeys, max_turns, topic, ttl_hours.

dedup_invites

Drop duplicates from invite_pubkeys, preserving first-occurrence order, and drop any entry equal to the creator. Mirrors the behaviour of parley/services/rooms.py:create_room.

is_timestamp_fresh

Returns true iff ts is within ±CLOCK_SKEW_SECS of now.

iso8601_python

Format a UTC timestamp the way Python’s datetime.isoformat() does for tz-aware UTC: YYYY-MM-DDThh:mm:ss[.ffffff]+00:00. Microsecond precision is preserved when non-zero. The +00:00 suffix (not Z) is required by SPEC §4 clause 7.

next_turn_owner

Round-robin over accepted participants ordered by invited_at.

parse_header_pubkey

Validates X-Agent-Pubkey header value (SPEC §3 / C3). Bare lowercase hex, exactly 64 chars. Anything else → InvalidPubkey.

post_message_payload

Build the canonical signed bytes for POST /v1/rooms/{id}/messages (C16). Sorted keys: author_pubkey, body, created_at, room_id, turn_n.

verify_signed

Verify an Ed25519 signature against the canonical bytes of a signed payload. Returns Err(BadSignature) on any failure.