informed-decision/informed_decision/presentation.py
tegwick 9e1f77e32b Build the T08 domain core with the engine behind a seam
approval-engine APPROVAL-WP-0002-T01 is still progress and its namespace has no
pods, so the live end-to-end proof cannot run. Built everything that does not
depend on it, with the engine behind a Protocol plus a fake carrying its real
refusal semantics, so its arrival is a wiring change rather than a build.

- memo.py: the Decision Memo, versions, binding document. Principal, Scope,
  Awareness and Hat are dataclasses rather than dicts because the canonicalizer
  requires a shape and a missing key should fail at construction rather than
  deep inside hashing — which is exactly how it failed twice while building
  this. Field names follow the governed canonicalizer (item_id, severity,
  locator): the published vectors are the contract, so the object was aligned to
  them rather than the reverse.
- presentation.py: the sole writer of view_hash. One writer, one canonicalizer,
  one place to audit. Acknowledgment is an explicit method call and nothing
  infers it from scroll, dwell or focus.
- disposition.py: verbs and guards G_NOAGENT, G_STEP, G_PRES, G_ACK, G_REASONS,
  G_SEALED. accept is ABSENT from weak steps rather than present-and-disabled,
  because a greyed-out accept still teaches the wrong model. Only accept reaches
  the engine; a memo return is not represented there at all.
- provenance.py: claim routes per A-16. assert_human_control_dischargeable
  refuses a registration-supplied human, so PR-11's limitation fires at the
  point of use instead of sitting in a document.
- evidence.py: local outbox, commitment-only records carrying the
  GH-DEC-2026-014 §4 existence assertion, per-class reconciliation counts, and a
  custody-locator guard that rejects credentialed URLs (PR-12).
- approval_client.py: 409 duplicate_approver is success, 409 conflict terminal,
  503 fail-closed, approval:consume refused before a token is requested.

87 tests pass, including every negative case in the Use Case Catalog and that a
fail-closed outcome is recorded as a stance application with no verb field —
never as a decline, because the human did not make one.

T08 stays progress: the live proof is the remainder.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V3W1dQG7GFFM9d94jFx7iR

Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 1565372@bnt-lap001
Assistant-Session: 16bb2f25-b34c-49ef-8e94-5fec3567a568
2026-09-10 20:38:20 +02:00

92 lines
2.7 KiB
Python

"""Presentation records — the sole writer of ``view_hash``.
One writer, one canonicalizer, one place to audit. A second path that computes
a hash is a defect, not an optimisation (`ArchitectureBlueprint` §3).
A presentation is a record of an event that happened. It is append-only:
editing one is falsifying evidence.
"""
from __future__ import annotations
import uuid
from dataclasses import dataclass, field
from datetime import datetime, timezone
from enum import Enum
from .canonicalize import awareness_hash, view_hash
from .memo import Awareness, Memo
from .provenance import Claim
class Phase(str, Enum):
PRE_BIND = "pre_bind"
BIND = "bind"
POST_BIND = "post_bind"
def _now() -> str:
return datetime.now(timezone.utc).isoformat(timespec="seconds").replace("+00:00", "Z")
@dataclass(frozen=True)
class Presentation:
id: str
memo_id: str
memo_version: int
principal_sub: str
locale: str
ui_release: str
rendered_at: str
view_hash: str
awareness_hash: str
phase: Phase
#: Co-reference to the act (GH-DEC-2026-012 R3). The identifier only.
approval_id: str | None = None
#: Claims stored WITH their route, never as bare strings (PR-09, PR-11).
tenant: Claim | None = None
principal_type: Claim | None = None
acked_highlight_ids: frozenset[str] = field(default_factory=frozenset)
def with_ack(self, highlight_id: str) -> "Presentation":
"""Acknowledgment is an explicit act.
Never inferred from scroll position, dwell time, focus or viewport
intersection (PR-21). Only this method records one, and only a
deliberate control activation calls it.
"""
from dataclasses import replace
return replace(self, acked_highlight_ids=self.acked_highlight_ids | {highlight_id})
def render(
memo: Memo,
*,
principal_sub: str,
tenant: Claim | None = None,
principal_type: Claim | None = None,
awareness: Awareness | None = None,
phase: Phase = Phase.PRE_BIND,
) -> Presentation:
"""Render a memo, producing exactly one presentation record.
This is the only function in the package that computes ``view_hash``.
"""
binding_doc = memo.binding_document()
awareness_doc = memo.awareness_document(awareness)
return Presentation(
id=f"pres-{uuid.uuid4()}",
memo_id=memo.id,
memo_version=memo.version,
principal_sub=principal_sub,
locale=memo.locale,
ui_release=memo.ui_release,
rendered_at=_now(),
view_hash=view_hash(binding_doc)["hex"],
awareness_hash=awareness_hash(awareness_doc)["hex"],
phase=phase,
approval_id=memo.approval_id,
tenant=tenant,
principal_type=principal_type,
)