feat: implement institutional service catalogue

src/govoplan_services/backend/__init__.py

@@ -0,0 +1 @@
+"""Services backend."""

src/govoplan_services/backend/db/__init__.py

@@ -0,0 +1,3 @@
+from govoplan_services.backend.db.models import ServiceDefinitionRevision
+
+__all__ = ["ServiceDefinitionRevision"]

src/govoplan_services/backend/db/models.py

@@ -0,0 +1,45 @@
+from __future__ import annotations
+
+from datetime import datetime
+from typing import Any
+import uuid
+
+from sqlalchemy import DateTime, ForeignKey, Index, JSON, String, Text, UniqueConstraint
+from sqlalchemy.orm import Mapped, mapped_column
+
+from govoplan_core.db.base import Base, TimestampMixin
+
+
+def new_uuid() -> str:
+    return str(uuid.uuid4())
+
+
+class ServiceDefinitionRevision(Base, TimestampMixin):
+    __tablename__ = "service_definition_revisions"
+    __table_args__ = (
+        UniqueConstraint("tenant_id", "service_id", "revision", name="uq_service_definition_revision"),
+        Index("ix_service_definition_current", "tenant_id", "service_id", "superseded_at"),
+        Index("ix_service_definition_catalogue", "tenant_id", "publication_state", "service_key"),
+    )
+
+    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=new_uuid)
+    tenant_id: Mapped[str] = mapped_column(String(36), nullable=False, index=True)
+    service_id: Mapped[str] = mapped_column(String(255), nullable=False, index=True)
+    service_key: Mapped[str] = mapped_column(String(255), nullable=False, index=True)
+    revision: Mapped[str] = mapped_column(String(120), nullable=False)
+    previous_revision_id: Mapped[str | None] = mapped_column(
+        ForeignKey("service_definition_revisions.id", ondelete="RESTRICT"),
+        nullable=True,
+        index=True,
+    )
+    publication_state: Mapped[str] = mapped_column(String(30), nullable=False, index=True)
+    valid_from: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
+    valid_to: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
+    recorded_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, index=True)
+    superseded_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True, index=True)
+    search_text: Mapped[str] = mapped_column(Text, nullable=False)
+    payload: Mapped[dict[str, Any]] = mapped_column(JSON, nullable=False)
+    created_by: Mapped[str | None] = mapped_column(String(255), nullable=True, index=True)
+
+
+__all__ = ["ServiceDefinitionRevision"]

src/govoplan_services/backend/manifest.py

@@ -0,0 +1,132 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+from govoplan_core.core.institutional import (
+    CAPABILITY_SERVICE_AVAILABILITY,
+    CAPABILITY_SERVICE_DEFINITIONS,
+)
+from govoplan_core.core.module_guards import drop_table_retirement_provider, persistent_table_uninstall_guard
+from govoplan_core.core.modules import (
+    CapabilityDocumentation,
+    DocumentationLink,
+    DocumentationTopic,
+    MigrationSpec,
+    ModuleContext,
+    ModuleInterfaceProvider,
+    ModuleManifest,
+    PermissionDefinition,
+    RoleTemplate,
+)
+from govoplan_core.core.provider_governance import declared_module_architecture
+from govoplan_core.db.base import Base
+from govoplan_services.backend.db import models as service_models
+from govoplan_services.backend.service import RegistryServiceAvailabilityEvaluator, SqlServiceDefinitionProvider
+
+
+MODULE_ID = "services"
+MODULE_NAME = "Services"
+MODULE_VERSION = "0.1.14"
+READ_SCOPE = "services:definition:read"
+WRITE_SCOPE = "services:definition:write"
+ADMIN_SCOPE = "services:definition:admin"
+
+
+def _permission(scope: str, label: str, description: str) -> PermissionDefinition:
+    module_id, resource, action = scope.split(":", 2)
+    return PermissionDefinition(
+        scope=scope,
+        label=label,
+        description=description,
+        category="Services",
+        level="tenant",
+        module_id=module_id,
+        resource=resource,
+        action=action,
+    )
+
+
+def _router(context: ModuleContext):
+    from govoplan_services.backend.router import configure_registry, router
+
+    configure_registry(context.registry)
+    return router
+
+
+def _definitions(_context: ModuleContext) -> SqlServiceDefinitionProvider:
+    return SqlServiceDefinitionProvider()
+
+
+def _availability(context: ModuleContext) -> RegistryServiceAvailabilityEvaluator:
+    return RegistryServiceAvailabilityEvaluator(context.registry)
+
+
+manifest = ModuleManifest(
+    id=MODULE_ID,
+    name=MODULE_NAME,
+    version=MODULE_VERSION,
+    optional_dependencies=("organizations", "mandates", "policy", "portal", "cases", "forms_runtime", "workflow_engine"),
+    provides_interfaces=(
+        ModuleInterfaceProvider(name="services.definition", version="0.1.0"),
+        ModuleInterfaceProvider(name="services.availability", version="0.1.0"),
+    ),
+    permissions=(
+        _permission(READ_SCOPE, "View service definitions", "View service definitions, bindings, and availability constraints."),
+        _permission(WRITE_SCOPE, "Manage service definitions", "Create and revise service definitions."),
+        _permission(ADMIN_SCOPE, "Administer services", "Administer service publication and recovery."),
+    ),
+    role_templates=(
+        RoleTemplate(slug="service_manager", name="Service manager", description="Manage the institutional service catalogue.", permissions=(READ_SCOPE, WRITE_SCOPE)),
+        RoleTemplate(slug="service_reader", name="Service reader", description="Inspect service definitions.", permissions=(READ_SCOPE,)),
+    ),
+    route_factory=_router,
+    capability_factories={
+        CAPABILITY_SERVICE_DEFINITIONS: _definitions,
+        CAPABILITY_SERVICE_AVAILABILITY: _availability,
+    },
+    capability_documentation={
+        CAPABILITY_SERVICE_DEFINITIONS: CapabilityDocumentation(label="Service definitions", summary="Provides exact versioned institutional Service definitions.", contract_version="0.1.0"),
+        CAPABILITY_SERVICE_AVAILABILITY: CapabilityDocumentation(label="Service availability", summary="Evaluates provider-known runtime availability requirements without widening constraints.", contract_version="0.1.0"),
+    },
+    migration_spec=MigrationSpec(
+        module_id=MODULE_ID,
+        metadata=Base.metadata,
+        script_location=str(Path(__file__).with_name("migrations") / "versions"),
+        retirement_supported=True,
+        retirement_provider=drop_table_retirement_provider(service_models.ServiceDefinitionRevision, label="Services"),
+        retirement_notes="Destructive retirement requires a database snapshot and removes service-definition history.",
+    ),
+    uninstall_guard_providers=(persistent_table_uninstall_guard(service_models.ServiceDefinitionRevision, label="Services"),),
+    documentation=(
+        DocumentationTopic(
+            id="services.catalogue",
+            title="Institutional service catalogue",
+            summary="Manage versioned service promises independently from presentation and case handling.",
+            body="Definitions retain audiences, prerequisites, evidence, responsibility, bindings, publication, and explainable availability requirements. Portal and Cases consume exact revisions through capabilities.",
+            layer="configured",
+            documentation_types=("admin", "user"),
+            audience=("user", "operator", "module_admin", "product_owner"),
+            links=(DocumentationLink(label="Services domain and recovery", href="govoplan-services/docs/SERVICES_DOMAIN.md", kind="repository"),),
+        ),
+    ),
+    architecture=declared_module_architecture(
+        layer="human_work_procedure",
+        kind="domain",
+        maturity="vertical_slice",
+        documentation_ref="docs/SERVICES_DOMAIN.md",
+        test_ref="tests/test_services.py",
+        known_limits=("The catalogue is API-first; Portal remains the presentation surface.",),
+        supported_authority_modes=("native_authoritative",),
+        owned_concepts=("service definition", "service publication", "service availability requirement"),
+        non_owned_concepts=("portal presentation", "case lifecycle", "form definition", "workflow definition"),
+        reference_packages=("product.service-to-decision",),
+        migration_docs=("docs/SERVICES_DOMAIN.md",),
+        recovery_docs=("docs/SERVICES_DOMAIN.md",),
+        security_docs=("docs/SERVICES_DOMAIN.md",),
+        operations_docs=("docs/SERVICES_DOMAIN.md",),
+    ),
+)
+
+
+def get_manifest() -> ModuleManifest:
+    return manifest

src/govoplan_services/backend/migrations/__init__.py

@@ -0,0 +1 @@
+"""Services migrations."""

src/govoplan_services/backend/migrations/versions/__init__.py

@@ -0,0 +1 @@
+"""Services migration revisions."""

src/govoplan_services/backend/migrations/versions/b9c2d3e4f5a6_v0114_services_baseline.py

@@ -0,0 +1,48 @@
+"""v0.1.14 Services baseline.
+
+Revision ID: b9c2d3e4f5a6
+Revises: None
+"""
+from __future__ import annotations
+
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = "b9c2d3e4f5a6"
+down_revision = None
+branch_labels = None
+depends_on = "4f2a9c8e7b6d"
+
+
+def upgrade() -> None:
+    op.create_table(
+        "service_definition_revisions",
+        sa.Column("id", sa.String(length=36), nullable=False),
+        sa.Column("tenant_id", sa.String(length=36), nullable=False),
+        sa.Column("service_id", sa.String(length=255), nullable=False),
+        sa.Column("service_key", sa.String(length=255), nullable=False),
+        sa.Column("revision", sa.String(length=120), nullable=False),
+        sa.Column("previous_revision_id", sa.String(length=36), nullable=True),
+        sa.Column("publication_state", sa.String(length=30), nullable=False),
+        sa.Column("valid_from", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("valid_to", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("recorded_at", sa.DateTime(timezone=True), nullable=False),
+        sa.Column("superseded_at", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("search_text", sa.Text(), nullable=False),
+        sa.Column("payload", sa.JSON(), nullable=False),
+        sa.Column("created_by", sa.String(length=255), nullable=True),
+        sa.Column("created_at", sa.DateTime(timezone=True), nullable=False),
+        sa.Column("updated_at", sa.DateTime(timezone=True), nullable=False),
+        sa.ForeignKeyConstraint(["previous_revision_id"], ["service_definition_revisions.id"], name=op.f("fk_service_definition_revisions_previous_revision_id_service_definition_revisions"), ondelete="RESTRICT"),
+        sa.PrimaryKeyConstraint("id", name=op.f("pk_service_definition_revisions")),
+        sa.UniqueConstraint("tenant_id", "service_id", "revision", name="uq_service_definition_revision"),
+    )
+    for column in ("tenant_id", "service_id", "service_key", "previous_revision_id", "publication_state", "recorded_at", "superseded_at", "created_by"):
+        op.create_index(op.f(f"ix_service_definition_revisions_{column}"), "service_definition_revisions", [column], unique=False)
+    op.create_index("ix_service_definition_current", "service_definition_revisions", ["tenant_id", "service_id", "superseded_at"], unique=False)
+    op.create_index("ix_service_definition_catalogue", "service_definition_revisions", ["tenant_id", "publication_state", "service_key"], unique=False)
+
+
+def downgrade() -> None:
+    op.drop_table("service_definition_revisions")

src/govoplan_services/backend/router.py

@@ -0,0 +1,123 @@
+from __future__ import annotations
+
+from typing import Any
+
+from fastapi import APIRouter, Depends, HTTPException, Query, status
+from sqlalchemy.orm import Session
+
+from govoplan_core.auth import ApiPrincipal, get_api_principal, has_scope
+from govoplan_core.core.institutional import InstitutionalContextError
+from govoplan_core.db.session import get_session
+from govoplan_services.backend.manifest import READ_SCOPE, WRITE_SCOPE
+from govoplan_services.backend.schemas import (
+    ServiceAvailabilityRequest,
+    ServiceListResponse,
+    ServiceWriteRequest,
+)
+from govoplan_services.backend.service import (
+    RegistryServiceAvailabilityEvaluator,
+    ServiceStoreError,
+    definition_from_mapping,
+    get_service_definition,
+    list_service_definitions,
+    record_service_definition,
+)
+
+
+router = APIRouter(prefix="/services", tags=["services"])
+_registry: object | None = None
+
+
+def configure_registry(registry: object | None) -> None:
+    global _registry
+    _registry = registry
+
+
+def _require(principal: ApiPrincipal, scope: str) -> None:
+    if not has_scope(principal, scope):
+        raise HTTPException(status_code=403, detail=f"Missing scope: {scope}")
+
+
+def _error(exc: Exception) -> HTTPException:
+    message = str(exc)
+    code = 409 if "conflict" in message.lower() or "already" in message.lower() else 400
+    return HTTPException(status_code=code, detail=message)
+
+
+@router.get("/definitions", response_model=ServiceListResponse)
+def api_list_services(
+    query: str = "",
+    publication_state: list[str] | None = Query(default=None),
+    limit: int = Query(default=100, ge=1, le=200),
+    session: Session = Depends(get_session),
+    principal: ApiPrincipal = Depends(get_api_principal),
+) -> ServiceListResponse:
+    _require(principal, READ_SCOPE)
+    items = list_service_definitions(
+        session,
+        principal,
+        query=query,
+        publication_states=publication_state,
+        limit=limit,
+    )
+    return ServiceListResponse(services=[item.to_dict(include_inspection=True) for item in items])
+
+
+@router.get("/definitions/{service_id}", response_model=dict[str, Any])
+def api_get_service(
+    service_id: str,
+    revision: str | None = None,
+    session: Session = Depends(get_session),
+    principal: ApiPrincipal = Depends(get_api_principal),
+) -> dict[str, Any]:
+    _require(principal, READ_SCOPE)
+    item = get_service_definition(session, principal, service_id=service_id, revision=revision)
+    if item is None:
+        raise HTTPException(status_code=404, detail="Service definition not found")
+    return item.to_dict(include_inspection=True)
+
+
+@router.post("/definitions", response_model=dict[str, Any], status_code=status.HTTP_201_CREATED)
+def api_record_service(
+    payload: ServiceWriteRequest,
+    session: Session = Depends(get_session),
+    principal: ApiPrincipal = Depends(get_api_principal),
+) -> dict[str, Any]:
+    _require(principal, WRITE_SCOPE)
+    try:
+        item = record_service_definition(
+            session,
+            principal,
+            definition=definition_from_mapping(payload.definition),
+            expected_revision=payload.expected_revision,
+        )
+        session.commit()
+    except (ServiceStoreError, InstitutionalContextError) as exc:
+        session.rollback()
+        raise _error(exc) from exc
+    return item.to_dict(include_inspection=True)
+
+
+@router.post("/availability", response_model=dict[str, Any])
+def api_service_availability(
+    payload: ServiceAvailabilityRequest,
+    principal: ApiPrincipal = Depends(get_api_principal),
+) -> dict[str, Any]:
+    _require(principal, READ_SCOPE)
+    try:
+        result = RegistryServiceAvailabilityEvaluator(_registry).evaluate_service_availability(
+            None,
+            principal,
+            definition=definition_from_mapping(payload.definition),
+            effective_at=payload.effective_at,
+        )
+    except (ServiceStoreError, InstitutionalContextError) as exc:
+        raise _error(exc) from exc
+    return {
+        "requirement_states": dict(result.requirement_states),
+        "reason_codes": list(result.reason_codes),
+        "evidence": [item.to_dict(include_inspection=True) for item in result.evidence],
+    }
+
+
+__all__ = ["configure_registry", "router"]

src/govoplan_services/backend/schemas.py

@@ -0,0 +1,27 @@
+from __future__ import annotations
+
+from datetime import datetime
+from typing import Any
+
+from pydantic import BaseModel, ConfigDict, Field
+
+
+class ServiceWriteRequest(BaseModel):
+    model_config = ConfigDict(extra="forbid")
+
+    definition: dict[str, Any]
+    expected_revision: str | None = Field(default=None, max_length=120)
+
+
+class ServiceListResponse(BaseModel):
+    services: list[dict[str, Any]]
+
+
+class ServiceAvailabilityRequest(BaseModel):
+    model_config = ConfigDict(extra="forbid")
+
+    definition: dict[str, Any]
+    effective_at: datetime
+
+
+__all__ = ["ServiceAvailabilityRequest", "ServiceListResponse", "ServiceWriteRequest"]

src/govoplan_services/backend/service.py

@@ -0,0 +1,360 @@
+from __future__ import annotations
+
+from datetime import UTC, datetime
+from typing import Any, Mapping, Sequence
+
+from sqlalchemy.orm import Session
+
+from govoplan_core.core.institutional import (
+    InstitutionalContextError,
+    InstitutionalReference,
+    ServiceAvailabilityAssessment,
+    ServiceDefinition,
+    TemporalRevision,
+)
+from govoplan_services.backend.db.models import ServiceDefinitionRevision
+
+
+_PUBLICATION_TRANSITIONS: dict[str, frozenset[str]] = {
+    "draft": frozenset({"draft", "published", "retired"}),
+    "published": frozenset({"published", "suspended", "retired"}),
+    "suspended": frozenset({"suspended", "published", "retired"}),
+    "retired": frozenset(),
+}
+
+
+class ServiceStoreError(ValueError):
+    pass
+
+
+def record_service_definition(
+    session: Session,
+    principal: object,
+    *,
+    definition: ServiceDefinition,
+    expected_revision: str | None = None,
+) -> ServiceDefinition:
+    tenant_id = _principal_tenant(principal)
+    _validate_definition(definition, tenant_id=tenant_id)
+    payload = definition.to_dict(include_inspection=True)
+    replay = (
+        session.query(ServiceDefinitionRevision)
+        .filter(
+            ServiceDefinitionRevision.tenant_id == tenant_id,
+            ServiceDefinitionRevision.service_id == definition.reference.object_id,
+            ServiceDefinitionRevision.revision == definition.temporal.revision,
+        )
+        .one_or_none()
+    )
+    if replay is not None:
+        if replay.payload != payload:
+            raise ServiceStoreError(
+                "A different Service payload already uses this revision."
+            )
+        return _definition_from_row(replay)
+
+    current = _current_row(
+        session,
+        tenant_id=tenant_id,
+        service_id=definition.reference.object_id,
+        lock=True,
+    )
+    _validate_temporal(definition.temporal)
+    if current is None:
+        if expected_revision is not None:
+            raise ServiceStoreError(
+                "Service revision conflict: no current revision exists."
+            )
+        collision = (
+            session.query(ServiceDefinitionRevision.id)
+            .filter(
+                ServiceDefinitionRevision.tenant_id == tenant_id,
+                ServiceDefinitionRevision.service_key == definition.key,
+                ServiceDefinitionRevision.superseded_at.is_(None),
+            )
+            .first()
+        )
+        if collision is not None:
+            raise ServiceStoreError("Service key is already in use in this tenant.")
+    else:
+        current_definition = _definition_from_row(current)
+        if expected_revision != current.revision:
+            raise ServiceStoreError(
+                "Service revision conflict: the expected revision is stale."
+            )
+        if definition.key != current_definition.key:
+            raise ServiceStoreError("A Service key cannot change across revisions.")
+        if definition.publication_state not in _PUBLICATION_TRANSITIONS[current.publication_state]:
+            raise ServiceStoreError(
+                f"Service publication transition {current.publication_state!r} to "
+                f"{definition.publication_state!r} is not allowed."
+            )
+        current.superseded_at = definition.temporal.recorded_at
+
+    row = ServiceDefinitionRevision(
+        tenant_id=tenant_id,
+        service_id=definition.reference.object_id,
+        service_key=definition.key,
+        revision=definition.temporal.revision,
+        previous_revision_id=current.id if current is not None else None,
+        publication_state=definition.publication_state,
+        valid_from=definition.temporal.valid_from,
+        valid_to=definition.temporal.valid_to,
+        recorded_at=_recorded_at(definition.temporal),
+        search_text=f"{definition.key} {definition.title}".casefold(),
+        payload=payload,
+        created_by=_principal_actor(principal),
+    )
+    session.add(row)
+    session.flush()
+    return _definition_from_row(row)
+
+
+def get_service_definition(
+    session: Session,
+    principal: object,
+    *,
+    service_id: str,
+    revision: str | None = None,
+) -> ServiceDefinition | None:
+    tenant_id = _principal_tenant(principal)
+    query = session.query(ServiceDefinitionRevision).filter(
+        ServiceDefinitionRevision.tenant_id == tenant_id,
+        ServiceDefinitionRevision.service_id == service_id,
+    )
+    if revision is None:
+        query = query.filter(ServiceDefinitionRevision.superseded_at.is_(None))
+    else:
+        query = query.filter(ServiceDefinitionRevision.revision == revision)
+    row = query.order_by(ServiceDefinitionRevision.recorded_at.desc()).first()
+    return _definition_from_row(row) if row is not None else None
+
+
+def list_service_definitions(
+    session: Session,
+    principal: object,
+    *,
+    query: str = "",
+    publication_states: Sequence[str] | None = None,
+    limit: int = 100,
+) -> tuple[ServiceDefinition, ...]:
+    tenant_id = _principal_tenant(principal)
+    if not 1 <= limit <= 200:
+        raise ServiceStoreError("Service list limit must be between 1 and 200.")
+    statement = session.query(ServiceDefinitionRevision).filter(
+        ServiceDefinitionRevision.tenant_id == tenant_id,
+        ServiceDefinitionRevision.superseded_at.is_(None),
+    )
+    if publication_states is not None:
+        statement = statement.filter(
+            ServiceDefinitionRevision.publication_state.in_(tuple(publication_states))
+        )
+    clean_query = query.strip().casefold()
+    if clean_query:
+        statement = statement.filter(
+            ServiceDefinitionRevision.search_text.contains(clean_query)
+        )
+    rows = statement.order_by(
+        ServiceDefinitionRevision.service_key.asc(),
+        ServiceDefinitionRevision.recorded_at.desc(),
+    ).limit(limit).all()
+    return tuple(_definition_from_row(row) for row in rows)
+
+
+class SqlServiceDefinitionProvider:
+    def get_service_definition(
+        self,
+        session: object,
+        principal: object,
+        *,
+        reference: InstitutionalReference,
+        effective_at: datetime | None = None,
+    ) -> ServiceDefinition | None:
+        tenant_id = _principal_tenant(principal)
+        if reference.kind != "service" or reference.tenant_id != tenant_id:
+            raise InstitutionalContextError(
+                "Service definition lookup requires a same-tenant Service reference."
+            )
+        item = get_service_definition(
+            _session(session),
+            principal,
+            service_id=reference.object_id,
+            revision=reference.version,
+        )
+        if item is None or (
+            effective_at is not None and not item.temporal.effective_at(effective_at)
+        ):
+            return None
+        return item
+
+    def list_service_definitions(
+        self,
+        session: object,
+        principal: object,
+        *,
+        tenant_id: str,
+        query: str = "",
+        limit: int = 100,
+    ) -> Sequence[ServiceDefinition]:
+        if tenant_id != _principal_tenant(principal):
+            raise InstitutionalContextError(
+                "Service catalogue lookup cannot cross tenants."
+            )
+        return list_service_definitions(
+            _session(session),
+            principal,
+            query=query,
+            publication_states=("published", "suspended"),
+            limit=limit,
+        )
+
+
+class RegistryServiceAvailabilityEvaluator:
+    def __init__(self, registry: object | None) -> None:
+        self._registry = registry
+
+    def evaluate_service_availability(
+        self,
+        session: object,
+        principal: object,
+        *,
+        definition: ServiceDefinition,
+        effective_at: datetime,
+    ) -> ServiceAvailabilityAssessment:
+        del session
+        tenant_id = _principal_tenant(principal)
+        if definition.reference.tenant_id != tenant_id:
+            raise InstitutionalContextError(
+                "Service availability cannot be evaluated across tenants."
+            )
+        states: dict[str, bool] = {}
+        reasons: list[str] = []
+        if not definition.temporal.effective_at(effective_at):
+            reasons.append("service.outside_effective_interval")
+        if definition.publication_state != "published":
+            reasons.append(f"service.publication.{definition.publication_state}")
+        for requirement in definition.availability_requirements:
+            if requirement.kind == "module":
+                states[requirement.key] = _registry_has(self._registry, requirement.reference)
+            elif requirement.kind == "capability":
+                states[requirement.key] = _registry_has_capability(
+                    self._registry,
+                    requirement.reference,
+                )
+        return ServiceAvailabilityAssessment(
+            requirement_states=states,
+            reason_codes=tuple(reasons),
+        )
+
+
+def definition_from_mapping(value: Mapping[str, object]) -> ServiceDefinition:
+    try:
+        return ServiceDefinition.from_mapping(value)
+    except InstitutionalContextError as exc:
+        raise ServiceStoreError(str(exc)) from exc
+
+
+def _current_row(
+    session: Session,
+    *,
+    tenant_id: str,
+    service_id: str,
+    lock: bool,
+) -> ServiceDefinitionRevision | None:
+    query = session.query(ServiceDefinitionRevision).filter(
+        ServiceDefinitionRevision.tenant_id == tenant_id,
+        ServiceDefinitionRevision.service_id == service_id,
+        ServiceDefinitionRevision.superseded_at.is_(None),
+    )
+    if lock:
+        query = query.with_for_update()
+    return query.one_or_none()
+
+
+def _definition_from_row(row: ServiceDefinitionRevision) -> ServiceDefinition:
+    payload: dict[str, Any] = dict(row.payload)
+    temporal = dict(payload.get("temporal") or {})
+    temporal["superseded_at"] = _datetime_text(row.superseded_at)
+    payload["temporal"] = temporal
+    return ServiceDefinition.from_mapping(payload)
+
+
+def _validate_definition(definition: ServiceDefinition, *, tenant_id: str) -> None:
+    if definition.reference.owner_module != "services":
+        raise ServiceStoreError("Service definitions must be owned by Services.")
+    if definition.reference.tenant_id != tenant_id:
+        raise ServiceStoreError("Service definitions cannot cross tenants.")
+    if definition.reference.version != definition.temporal.revision:
+        raise ServiceStoreError(
+            "Service reference version must match its temporal revision."
+        )
+    if definition.temporal.superseded_at is not None:
+        raise ServiceStoreError("Clients cannot set Service superseded_at.")
+
+
+def _validate_temporal(temporal: TemporalRevision) -> None:
+    _recorded_at(temporal)
+    if not str(temporal.change_reason or "").strip():
+        raise ServiceStoreError(
+            "A Service revision requires recorded_at and change_reason."
+        )
+
+
+def _recorded_at(temporal: TemporalRevision) -> datetime:
+    if temporal.recorded_at is None:
+        raise ServiceStoreError("A Service revision requires recorded_at.")
+    return temporal.recorded_at
+
+
+def _principal_tenant(principal: object) -> str:
+    tenant_id = str(getattr(principal, "tenant_id", "") or "").strip()
+    if not tenant_id:
+        raise InstitutionalContextError(
+            "Service operations require a tenant-bound principal."
+        )
+    return tenant_id
+
+
+def _principal_actor(principal: object) -> str | None:
+    for name in ("account_id", "identity_id", "membership_id"):
+        value = str(getattr(principal, name, "") or "").strip()
+        if value:
+            return value
+    return None
+
+
+def _session(value: object) -> Session:
+    if not hasattr(value, "query"):
+        raise InstitutionalContextError("Service provider requires a database session.")
+    return value  # type: ignore[return-value]
+
+
+def _registry_has(registry: object | None, module_id: str) -> bool:
+    return bool(registry is not None and hasattr(registry, "has") and registry.has(module_id))
+
+
+def _registry_has_capability(registry: object | None, capability: str) -> bool:
+    return bool(
+        registry is not None
+        and hasattr(registry, "has_capability")
+        and registry.has_capability(capability)
+    )
+
+
+def _datetime_text(value: datetime | None) -> str | None:
+    if value is None:
+        return None
+    if value.tzinfo is None:
+        value = value.replace(tzinfo=UTC)
+    return value.isoformat()
+
+
+__all__ = [
+    "RegistryServiceAvailabilityEvaluator",
+    "ServiceStoreError",
+    "SqlServiceDefinitionProvider",
+    "definition_from_mapping",
+    "get_service_definition",
+    "list_service_definitions",
+    "record_service_definition",
+]