Fence and reconcile workflow runtime effects

This commit is contained in:
2026-08-03 06:37:45 +02:00
parent a1cea1d162
commit fed8fbe6c3
10 changed files with 1669 additions and 29 deletions
@@ -0,0 +1,535 @@
from __future__ import annotations
from dataclasses import dataclass
import hashlib
import json
from typing import Mapping
from sqlalchemy.orm import Session, sessionmaker
from govoplan_core.core.automation import ActionDefinition
from govoplan_core.core.recovery import (
RecoveryGuaranteeError,
RecoveryMode,
RecoveryOperation,
RecoveryPlan,
RecoveryStatus,
)
from govoplan_core.core.recovery_runtime import (
DurableRecoveryOperation,
RecoveryOperationBusy,
RecoveryOperationStateConflict,
begin_durable_recovery_operation,
claim_durable_recovery_operation,
)
from govoplan_core.core.runtime_coordination import (
LeaseClaim,
acquire_lease,
assert_lease_fence,
process_runtime_identity,
release_lease,
)
from govoplan_workflow_engine.backend.db.models import (
WorkflowDefinitionRevision,
WorkflowInstance,
WorkflowInstanceStep,
)
class WorkflowRecoveryError(RuntimeError):
pass
class WorkflowRecoveryBusy(WorkflowRecoveryError):
pass
class WorkflowRecoveryConflict(WorkflowRecoveryError):
def __init__(self, operation_id: str, status: str) -> None:
self.operation_id = operation_id
self.status = status
super().__init__(
f"Workflow action recovery is {status}; reconcile it first"
)
@dataclass(frozen=True, slots=True)
class WorkflowRecoveryDeclaration:
operation_type: str
mode: RecoveryMode | None
boundaries: tuple[Mapping[str, object], ...]
verification: tuple[str, ...]
WORKFLOW_RECOVERY_OPERATIONS = (
WorkflowRecoveryDeclaration(
operation_type="instance.state-transition",
mode=RecoveryMode.ATOMIC,
boundaries=(
{
"name": "worker-claim",
"classification": "fenced",
"resume": "a current process identity and distributed fence are required",
},
{
"name": "instance-transition",
"classification": "atomic",
"resume": "the pinned revision, step, event, and instance state commit together",
},
),
verification=(
"verify the pinned definition revision and current step",
"verify the process still owns the distributed fence before commit",
),
),
WorkflowRecoveryDeclaration(
operation_type="activity.external-effect",
mode=None,
boundaries=(
{
"name": "action-preview",
"classification": "recomputable",
"resume": "revalidate capability, authority, input, and preview",
},
{
"name": "provider-dispatch",
"classification": "outcome-unknown",
"resume": "verify by stable provider idempotency key before retry",
},
{
"name": "workflow-projection",
"classification": "verified",
"resume": "commit the local projection with terminal recovery evidence",
},
),
verification=(
"verify the pinned definition and canonical action request hashes",
"verify the provider result and every announced effect",
"reconcile an uncertain provider outcome before continuation",
),
),
)
def workflow_session_factory(session: Session) -> sessionmaker[Session]:
bind = session.get_bind()
if bind is None:
raise WorkflowRecoveryError("Workflow recovery requires a database bind")
return sessionmaker(bind=bind, expire_on_commit=False)
def canonical_sha256(value: object) -> str:
encoded = json.dumps(
value,
sort_keys=True,
separators=(",", ":"),
ensure_ascii=True,
default=str,
).encode("utf-8")
return hashlib.sha256(encoded).hexdigest()
@dataclass(slots=True)
class WorkflowActionRecovery:
operation: DurableRecoveryOperation | None
operation_id: str
mode: RecoveryMode
call_number: int
replayed: bool
def checkpoint_dispatch(
self,
session: Session,
*,
instance: WorkflowInstance,
step: WorkflowInstanceStep,
action_key: str,
capability_name: str,
) -> None:
if self.operation is None:
return
previous = dict(step.handoff or {})
step.handoff = {
**previous,
"kind": "module_action",
"state": "running",
"action_key": action_key,
"capability": capability_name,
"allowed_actions": ["cancel"],
"recovery": {
"operation_id": self.operation_id,
"mode": self.mode.value,
"status": RecoveryStatus.RUNNING.value,
"call_number": self.call_number,
"boundary": "provider-dispatch",
"requires_attention": False,
},
}
step.status = "running"
instance.status = "running"
try:
session.commit()
self.operation.checkpoint(
kind="provider-dispatch",
summary="Provider dispatch crossed the recoverable effect boundary",
evidence={
"effect_started": self.mode != RecoveryMode.ATOMIC,
"action_key": action_key,
"capability": capability_name,
"call_number": self.call_number,
},
)
except Exception as exc:
session.rollback()
raise WorkflowRecoveryError(
"Workflow action dispatch evidence could not be persisted"
) from exc
def commit_conclusive_result(
self,
session: Session,
*,
provider_state: str,
result_sha256: str,
observed_effects_sha256: str,
) -> None:
if self.operation is None:
return
evidence = {
"verified": True,
"checks": {
"provider_state": provider_state,
"result_sha256": result_sha256,
"observed_effects_sha256": observed_effects_sha256,
"call_number": self.call_number,
},
}
if self.mode == RecoveryMode.ATOMIC:
self.operation.commit_atomic_success(session, evidence=evidence)
else:
self.operation.commit_verified_success(session, evidence=evidence)
def commit_unknown(
self,
session: Session,
*,
error_type: str,
message: str,
) -> None:
if self.operation is None:
raise WorkflowRecoveryError(
"A replayed action cannot acquire an unknown outcome"
)
try:
session.commit()
self.operation.unresolved(
status=RecoveryStatus.OUTCOME_UNKNOWN,
summary="The provider acknowledgement was not conclusive",
evidence={
"effect_started": self.mode != RecoveryMode.ATOMIC,
"error_type": error_type,
"call_number": self.call_number,
},
failure_summary=message,
)
except Exception as exc:
session.rollback()
raise WorkflowRecoveryError(
"Workflow action uncertainty could not be recorded"
) from exc
def commit_definitive_failure(
self,
session: Session,
*,
summary: str,
error_type: str,
) -> None:
if self.operation is None:
return
evidence = {
"verified": True,
"checks": {
"effect_started": False,
"error_type": error_type,
"call_number": self.call_number,
},
}
if self.mode == RecoveryMode.ATOMIC:
self.operation.commit_atomic_failure(
session,
summary=summary,
evidence=evidence,
)
else:
self.operation.fail(summary=summary, evidence=evidence)
session.commit()
def begin_workflow_action_recovery(
session: Session,
*,
instance: WorkflowInstance,
step: WorkflowInstanceStep,
revision: WorkflowDefinitionRevision,
definition: ActionDefinition,
capability_name: str,
request_idempotency_key: str,
action_input: Mapping[str, object],
preview_payload: Mapping[str, object],
backup_reference: str | None = None,
approval_reference: str | None = None,
) -> WorkflowActionRecovery:
previous_recovery = (
step.handoff.get("recovery")
if isinstance(step.handoff, Mapping)
else None
)
call_number = 1
if isinstance(previous_recovery, Mapping):
call_number = max(
1,
int(
previous_recovery.get("next_call_number")
or previous_recovery.get("call_number")
or 1
),
)
mode = RecoveryMode(definition.recovery_mode)
plan = _action_recovery_plan(
definition,
mode=mode,
backup_reference=backup_reference,
approval_reference=approval_reference,
)
request_sha256 = canonical_sha256(dict(action_input))
preview_sha256 = canonical_sha256(dict(preview_payload))
access_context_sha256 = canonical_sha256(instance.authorization_)
action_contract_sha256 = canonical_sha256(
{
"action_key": definition.action_key,
"owner_module": definition.owner_module,
"contract_version": definition.contract_version,
"recovery_mode": definition.recovery_mode,
"recovery_verification": list(definition.recovery_verification),
"expected_effect_keys": list(definition.expected_effect_keys),
}
)
session.commit()
try:
started = begin_durable_recovery_operation(
workflow_session_factory(session),
identity=process_runtime_identity(),
module_id="workflow_engine",
operation_type="activity.external-effect",
idempotency_key=(
f"workflow-step:{step.id}:action-call:{call_number}"
),
request={
"tenant_id": instance.tenant_id,
"instance_id": instance.id,
"step_id": step.id,
"node_id": step.node_id,
"definition_revision_id": revision.id,
"definition_hash": revision.content_hash,
"action_key": definition.action_key,
"capability": capability_name,
"action_contract_sha256": action_contract_sha256,
"action_input_sha256": request_sha256,
"preview_sha256": preview_sha256,
"provider_idempotency_sha256": canonical_sha256(
request_idempotency_key
),
"call_number": call_number,
},
recovery_plan=plan,
precondition_evidence={
"definition_hash": revision.content_hash,
"action_contract_sha256": action_contract_sha256,
"action_input_sha256": request_sha256,
"preview_sha256": preview_sha256,
"access_context_sha256": access_context_sha256,
"call_number": call_number,
},
lease_resource_key=f"workflow:step:{step.id}",
lease_ttl_seconds=300,
resource_type="workflow_instance_step",
resource_id=step.id,
metadata={
"resources": ["postgresql", "module-provider"],
"workflow_instance_id": instance.id,
"action_key": definition.action_key,
"capability": capability_name,
},
)
except RecoveryOperationBusy as exc:
raise WorkflowRecoveryBusy(
"Another runtime owns this Workflow action step"
) from exc
except RecoveryOperationStateConflict as exc:
raise WorkflowRecoveryConflict(exc.operation_id, exc.status) from exc
except (RecoveryGuaranteeError, RuntimeError, ValueError) as exc:
raise WorkflowRecoveryError(
"The recovery ledger is unavailable; the module action did not start"
) from exc
return WorkflowActionRecovery(
operation=started.operation,
operation_id=started.operation_id,
mode=mode,
call_number=call_number,
replayed=started.replayed,
)
def claim_workflow_action_recovery(
session: Session,
*,
operation_id: str,
) -> DurableRecoveryOperation:
try:
return claim_durable_recovery_operation(
workflow_session_factory(session),
identity=process_runtime_identity(),
operation_id=operation_id,
lease_ttl_seconds=300,
)
except (RecoveryGuaranteeError, RuntimeError) as exc:
raise WorkflowRecoveryError(
"The Workflow action outcome cannot currently be reconciled"
) from exc
def reconcile_stale_workflow_action_recovery(
session: Session,
*,
operation_id: str,
) -> str:
try:
handle = claim_durable_recovery_operation(
workflow_session_factory(session),
identity=process_runtime_identity(),
operation_id=operation_id,
lease_ttl_seconds=300,
)
except RecoveryOperationBusy as exc:
raise WorkflowRecoveryBusy(
"Another runtime still owns this Workflow action step"
) from exc
except RecoveryOperationStateConflict as exc:
return exc.status
except (RecoveryGuaranteeError, RuntimeError) as exc:
raise WorkflowRecoveryError(
"The stale Workflow action fence could not be reconciled"
) from exc
handle.release_unresolved()
session.expire_all()
operation = session.get(RecoveryOperation, operation_id)
if operation is None:
raise WorkflowRecoveryError(
"The reconciled Workflow recovery operation is unavailable"
)
return str(operation.status)
def workflow_action_recovery_state(
session: Session,
*,
operation_id: str,
) -> dict[str, object] | None:
operation = session.get(RecoveryOperation, operation_id)
if operation is None or operation.module_id != "workflow_engine":
return None
return {
"operation_id": operation.id,
"mode": operation.mode,
"status": operation.status,
"requires_attention": operation.status
in {
RecoveryStatus.OUTCOME_UNKNOWN.value,
RecoveryStatus.RECOVERY_REQUIRED.value,
RecoveryStatus.MANUAL_INTERVENTION.value,
},
"failure_summary": operation.failure_summary,
}
def acquire_workflow_state_fence(
session: Session,
*,
resource_key: str,
ttl_seconds: int = 120,
) -> LeaseClaim | None:
identity = process_runtime_identity()
return acquire_lease(
session,
installation_id=identity.installation_id,
resource_key=resource_key,
holder_node_id=identity.node_id,
holder_incarnation=identity.incarnation,
ttl_seconds=ttl_seconds,
metadata={"module_id": "workflow_engine", "kind": "state-transition"},
)
def release_workflow_state_fence(session: Session, claim: LeaseClaim) -> None:
assert_lease_fence(session, claim)
release_lease(session, claim)
def _action_recovery_plan(
definition: ActionDefinition,
*,
mode: RecoveryMode,
backup_reference: str | None,
approval_reference: str | None,
) -> RecoveryPlan:
if mode == RecoveryMode.SNAPSHOT_RESTORE and not backup_reference:
raise WorkflowRecoveryError(
"Snapshot-restore actions require a pinned recovery backup reference"
)
if mode == RecoveryMode.IRREVERSIBLE and not approval_reference:
raise WorkflowRecoveryError(
"Irreversible actions require a pinned approval reference"
)
return RecoveryPlan(
mode=mode,
preconditions=(
"the pinned Workflow revision and action contract hashes are present",
"the current authority and provider capability were revalidated",
"the action step owns a distributed execution fence",
),
compensation_steps=(
"invoke the provider-declared compensation action",
"verify the domain invariant after compensation",
)
if mode == RecoveryMode.COMPENSATION
else (),
forward_recovery_steps=(
"inspect the provider by stable idempotency key",
"record whether the announced effect occurred",
"continue or retry only after the outcome is proven",
)
if mode == RecoveryMode.FORWARD_RECOVERY
else (),
verification_steps=tuple(definition.recovery_verification),
backup_reference=backup_reference,
approval_reference=approval_reference,
)
__all__ = [
"WORKFLOW_RECOVERY_OPERATIONS",
"WorkflowActionRecovery",
"WorkflowRecoveryDeclaration",
"WorkflowRecoveryBusy",
"WorkflowRecoveryConflict",
"WorkflowRecoveryError",
"acquire_workflow_state_fence",
"begin_workflow_action_recovery",
"canonical_sha256",
"claim_workflow_action_recovery",
"release_workflow_state_fence",
"reconcile_stale_workflow_action_recovery",
"workflow_action_recovery_state",
"workflow_session_factory",
]