Files
huskies/server/src/pipeline_state/transition.rs
T
2026-05-14 09:38:15 +00:00

476 lines
18 KiB
Rust

//! Pure state transition functions for pipeline and execution state machines.
use chrono::Utc;
use serde::{Deserialize, Serialize};
use super::{
AgentName, ArchiveReason, BranchName, ExecutionState, GitSha, MergeFailureKind, PlanState,
Stage, StoryId, TransitionError, stage_label,
};
// ── Pipeline events ─────────────────────────────────────────────────────────
/// Events that drive Stage transitions. Each variant carries the data needed
/// to construct the destination state, so the transition function can never
/// accidentally land in an underspecified state.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum PipelineEvent {
/// Dependencies met; promote from backlog.
DepsMet,
/// Coder starting gates.
GatesStarted,
/// Gates passed — ready to merge.
GatesPassed {
feature_branch: BranchName,
commits_ahead: std::num::NonZeroU32,
},
/// Gates failed; retry.
GatesFailed { reason: String },
/// QA mode is "server" — skip QA, go straight to merge.
QaSkipped {
feature_branch: BranchName,
commits_ahead: std::num::NonZeroU32,
},
/// Mergemaster squash succeeded.
MergeSucceeded { merge_commit: GitSha },
/// Merge pipeline failed (conflicts or gate failures); story moves to
/// `Stage::MergeFailure` awaiting human intervention or retry.
MergeFailed { kind: MergeFailureKind },
/// Mergemaster gave up after retry budget.
MergeFailedFinal { reason: String },
/// Story accepted (Done → Archived).
Accepted,
/// User blocked the story.
Block { reason: String },
/// User unblocked.
Unblock,
/// User abandoned.
Abandon,
/// Story superseded by another.
Supersede { by: StoryId },
/// Story put on review hold.
ReviewHold { reason: String },
/// Story rejected by QA or reviewer.
Reject { reason: String },
/// Story triaged from upcoming to backlog.
Triage,
/// Direct completion — item closed without going through the full pipeline
/// (e.g. spike auto-merge, bug closure, manual acceptance).
Close,
/// Manual demotion back to backlog from an active stage.
Demote,
/// Story 945: freeze a story at its current stage.
Freeze,
/// Story 945: unfreeze a frozen story, returning to `resume_to`.
Unfreeze,
/// Story 945: clear a `ReviewHold`, returning to `resume_to`.
ReviewHoldCleared,
/// Story 945: mergemaster has been auto-spawned and gave up; transitions
/// `Stage::MergeFailure` → `Stage::MergeFailureFinal`.
MergemasterAttempted,
/// Story 971: user sends a MergeFailure story back to Coding for coder fixup.
FixupRequested,
/// Story 972: user sends a MergeFailure story back to Qa for re-review.
ReQueuedForQa,
/// Story 973: user aborts an in-flight merge, sending the story back to Coding.
MergeAborted,
/// Story 974: user re-opens a Done story for a post-merge hotfix, sending it back to Coding.
HotfixRequested,
}
// ── Per-node execution events ───────────────────────────────────────────────
/// Events that drive per-node [`ExecutionState`] transitions (agent lifecycle).
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum ExecutionEvent {
SpawnRequested { agent: AgentName },
SpawnedSuccessfully,
Heartbeat,
HitRateLimit { resume_at: chrono::DateTime<Utc> },
Exited { exit_code: i32 },
Stopped,
Reset,
}
// ── Label helper ────────────────────────────────────────────────────────────
/// Human-readable label for a `PipelineEvent` variant.
pub fn event_label(e: &PipelineEvent) -> &'static str {
match e {
PipelineEvent::DepsMet => "DepsMet",
PipelineEvent::GatesStarted => "GatesStarted",
PipelineEvent::GatesPassed { .. } => "GatesPassed",
PipelineEvent::GatesFailed { .. } => "GatesFailed",
PipelineEvent::QaSkipped { .. } => "QaSkipped",
PipelineEvent::MergeSucceeded { .. } => "MergeSucceeded",
PipelineEvent::MergeFailed { .. } => "MergeFailed",
PipelineEvent::MergeFailedFinal { .. } => "MergeFailedFinal",
PipelineEvent::Accepted => "Accepted",
PipelineEvent::Block { .. } => "Block",
PipelineEvent::Unblock => "Unblock",
PipelineEvent::Abandon => "Abandon",
PipelineEvent::Supersede { .. } => "Supersede",
PipelineEvent::ReviewHold { .. } => "ReviewHold",
PipelineEvent::Reject { .. } => "Reject",
PipelineEvent::Triage => "Triage",
PipelineEvent::Close => "Close",
PipelineEvent::Demote => "Demote",
PipelineEvent::Freeze => "Freeze",
PipelineEvent::Unfreeze => "Unfreeze",
PipelineEvent::ReviewHoldCleared => "ReviewHoldCleared",
PipelineEvent::MergemasterAttempted => "MergemasterAttempted",
PipelineEvent::FixupRequested => "FixupRequested",
PipelineEvent::ReQueuedForQa => "ReQueuedForQa",
PipelineEvent::MergeAborted => "MergeAborted",
PipelineEvent::HotfixRequested => "HotfixRequested",
}
}
// ── The pipeline transition function ────────────────────────────────────────
/// Pure state transition. Takes the current Stage and an event, returns the
/// new Stage or a TransitionError. Side effects are dispatched separately
/// via the event bus.
pub fn transition(state: Stage, event: PipelineEvent) -> Result<Stage, TransitionError> {
use PipelineEvent::*;
use Stage::*;
let sl = stage_label(&state);
let el = event_label(&event);
let invalid = || TransitionError::InvalidTransition {
from_stage: sl.to_string(),
event: el.to_string(),
};
let now = Utc::now();
match (state, event) {
// ── Triage: upcoming → backlog ──────────────────────────────────
(Upcoming, Triage) => Ok(Backlog),
// ── Forward path ────────────────────────────────────────────────
(Backlog, DepsMet) => Ok(Coding {
claim: None,
plan: PlanState::Missing,
}),
(Coding { .. }, GatesStarted) => Ok(Qa),
(
Coding { .. },
QaSkipped {
feature_branch,
commits_ahead,
},
) => Ok(Merge {
feature_branch,
commits_ahead,
claim: None,
}),
(
Qa,
GatesPassed {
feature_branch,
commits_ahead,
},
) => Ok(Merge {
feature_branch,
commits_ahead,
claim: None,
}),
(Qa, GatesFailed { .. }) => Ok(Coding {
claim: None,
plan: PlanState::Missing,
}),
(Merge { .. }, MergeSucceeded { merge_commit }) => Ok(Done {
merged_at: now,
merge_commit,
}),
// ── Done → Archived(Completed) ──────────────────────────────────
(Done { .. }, Accepted) => Ok(Archived {
archived_at: now,
reason: ArchiveReason::Completed,
}),
// ── MergeFailure → Done (manual recovery) ───────────────────────
// Allows a human operator to accept a story whose merge permanently
// failed, marking it Done without going through the normal merge path.
(MergeFailure { .. }, Accepted) => Ok(Done {
merged_at: now,
merge_commit: GitSha("manual".to_string()),
}),
// ── Block: any active → Blocked ──────────────────────────────
(Backlog, Block { reason })
| (Coding { .. }, Block { reason })
| (Qa, Block { reason })
| (Merge { .. }, Block { reason })
| (MergeFailure { .. }, Block { reason })
| (MergeFailureFinal { .. }, Block { reason }) => Ok(Blocked { reason }),
// Story 945: ReviewHold no longer auto-archives. It transitions the
// story to `Stage::ReviewHold { resume_to, reason }`, preserving the
// current stage as the resume target so a reviewer can clear the
// hold and continue.
(
s @ (Backlog | Coding { .. } | Qa | Merge { .. }),
PipelineEvent::ReviewHold { reason },
) => Ok(Stage::ReviewHold {
resume_to: Box::new(s),
reason,
}),
// ── MergeFailed: Merge → MergeFailure (recoverable intermediate) ──
(
Merge {
feature_branch,
commits_ahead,
..
},
MergeFailed { kind },
) => Ok(MergeFailure {
kind,
feature_branch,
commits_ahead,
}),
// ── MergeFailure self-loop: repeated failure is a no-op ─────────────
// When the mergemaster retries and fails again while the story is already
// in MergeFailure, treat it as a silent self-transition so callers can
// detect the no-op via `fired.before == MergeFailure` and skip re-notifying.
(
MergeFailure {
feature_branch,
commits_ahead,
..
},
MergeFailed { kind },
) => Ok(MergeFailure {
kind,
feature_branch,
commits_ahead,
}),
(Merge { .. }, MergeFailedFinal { reason }) => Ok(Archived {
archived_at: now,
reason: ArchiveReason::MergeFailed { reason },
}),
// ── Abandon / supersede from any active or done stage ───────────
(Upcoming, Abandon)
| (Backlog, Abandon)
| (Coding { .. }, Abandon)
| (Qa, Abandon)
| (Merge { .. }, Abandon)
| (Done { .. }, Abandon) => Ok(Abandoned { ts: now }),
(Upcoming, Supersede { by })
| (Backlog, Supersede { by })
| (Coding { .. }, Supersede { by })
| (Qa, Supersede { by })
| (Merge { .. }, Supersede { by })
| (Done { .. }, Supersede { by }) => Ok(Superseded {
ts: now,
superseded_by: by,
}),
// ── Reject from any active stage or QA ──────────────────────────
(Backlog, Reject { reason })
| (Coding { .. }, Reject { reason })
| (Qa, Reject { reason })
| (Merge { .. }, Reject { reason }) => Ok(Rejected { ts: now, reason }),
// ── Demote: send an active item back to backlog ────────────────
// `Blocked + Demote → Backlog` lets operators park a stuck story in
// the backlog while waiting on dependent fixes, without losing it to
// Archived. Unlike `Unblock` (Blocked → Coding), this does not
// re-enter the active flow.
(Coding { .. }, Demote)
| (Qa, Demote)
| (Merge { .. }, Demote)
| (Blocked { .. }, Demote) => Ok(Backlog),
// ── Close: direct completion from any active stage ─────────────
(Backlog, Close) | (Coding { .. }, Close) | (Qa, Close) | (Merge { .. }, Close) => {
Ok(Done {
merged_at: now,
merge_commit: GitSha("closed".to_string()),
})
}
// ── Freeze: any non-terminal stage → Frozen { resume_to } ──────
(
s @ (Upcoming
| Backlog
| Coding { .. }
| Qa
| Merge { .. }
| Blocked { .. }
| MergeFailure { .. }
| MergeFailureFinal { .. }
| Stage::ReviewHold { .. }),
Freeze,
) => Ok(Frozen {
resume_to: Box::new(s),
}),
// ── Unfreeze: Frozen → resume_to ───────────────────────────────
(Frozen { resume_to }, Unfreeze) => Ok(*resume_to),
// ── ReviewHoldCleared: ReviewHold → resume_to ──────────────────
(Stage::ReviewHold { resume_to, .. }, ReviewHoldCleared) => Ok(*resume_to),
// ── FixupRequested: MergeFailure → Coding (coder fixup) ────────
(MergeFailure { .. }, FixupRequested) => Ok(Coding {
claim: None,
plan: PlanState::Missing,
}),
// ── FixupRequested: MergeFailureFinal → Coding (operator override)
//
// The exhausted-respawn-budget terminal state is not actually
// terminal as far as the operator is concerned; a human can decide
// the gate failure is fixable and send the story back for another
// coder attempt. The budget counter is a mergemaster bookkeeping
// detail, not a hard ceiling.
(MergeFailureFinal { .. }, FixupRequested) => Ok(Coding {
claim: None,
plan: PlanState::Missing,
}),
// ── ReQueuedForQa: MergeFailure → Qa (re-review) ────────────────
(MergeFailure { .. }, ReQueuedForQa) => Ok(Qa),
// ── MergeAborted: Merge → Coding (abort in-flight merge) ─────────
(Merge { .. }, MergeAborted) => Ok(Coding {
claim: None,
plan: PlanState::Missing,
}),
// ── HotfixRequested: Done → Coding (post-merge hotfix) ───────────
// Allows reopening a completed story so a coder can apply a hotfix.
// A fresh feature branch is forked from master when auto-assign spawns
// the coder.
(Done { .. }, HotfixRequested) => Ok(Coding {
claim: None,
plan: PlanState::Missing,
}),
// ── MergemasterAttempted: MergeFailure → MergeFailureFinal ─────
(MergeFailure { kind, .. }, MergemasterAttempted) => Ok(MergeFailureFinal { kind }),
(MergeFailureFinal { kind }, MergemasterAttempted) => Ok(MergeFailureFinal { kind }),
// ── Unblock: from Frozen/ReviewHold → resume_to ────────────────
(Frozen { resume_to }, Unblock) => Ok(*resume_to),
(Stage::ReviewHold { resume_to, .. }, Unblock) => Ok(*resume_to),
// ── Unblock: Blocked → Coding ─────────────────────────────────
(Blocked { .. }, Unblock) => Ok(Coding {
claim: None,
plan: PlanState::Missing,
}),
// ── Unblock MergeFailure → Merge (re-attempt) ────────────────────
// `unblock_story` on a failed merge re-queues it for merge, restoring
// the exact `Merge { feature_branch, commits_ahead }` that was in place
// before the failure so the mergemaster can retry immediately.
(
MergeFailure {
feature_branch,
commits_ahead,
..
},
Unblock,
) => Ok(Merge {
feature_branch,
commits_ahead,
claim: None,
}),
// ── Demote MergeFailure → Backlog (manual parking) ───────────────
// Lets operators park a failed-merge story in the backlog without an
// agent retry. Complements `Unblock` (→ Coding) which triggers an
// immediate retry by a coder agent.
(MergeFailure { .. }, Demote) => Ok(Backlog),
// ── Legacy unblock: Archived(Blocked|MergeFailed) → Backlog ──
(
Archived {
reason: ArchiveReason::Blocked { .. },
..
},
Unblock,
)
| (
Archived {
reason: ArchiveReason::MergeFailed { .. },
..
},
Unblock,
) => Ok(Backlog),
// ── Everything else is invalid ──────────────────────────────────
_ => Err(invalid()),
}
}
// ── The execution state transition function ─────────────────────────────────
/// Pure execution-state transition. Takes the current ExecutionState and an
/// ExecutionEvent, returns the new ExecutionState or a TransitionError.
pub fn execution_transition(
state: ExecutionState,
event: ExecutionEvent,
) -> Result<ExecutionState, TransitionError> {
use ExecutionEvent::*;
use ExecutionState::*;
let now = Utc::now();
match (state, event) {
(Idle, SpawnRequested { agent }) => Ok(Pending { agent, since: now }),
(Pending { agent, .. }, SpawnedSuccessfully) => Ok(Running {
agent,
started_at: now,
last_heartbeat: now,
}),
(
Running {
agent, started_at, ..
},
Heartbeat,
) => Ok(Running {
agent,
started_at,
last_heartbeat: now,
}),
(Running { agent, .. }, HitRateLimit { resume_at })
| (Pending { agent, .. }, HitRateLimit { resume_at }) => {
Ok(RateLimited { agent, resume_at })
}
(RateLimited { agent, .. }, SpawnedSuccessfully) => Ok(Running {
agent,
started_at: now,
last_heartbeat: now,
}),
(Running { agent, .. }, Exited { exit_code })
| (Pending { agent, .. }, Exited { exit_code })
| (RateLimited { agent, .. }, Exited { exit_code }) => Ok(Completed {
agent,
exit_code,
completed_at: now,
}),
(_, Stopped) | (_, Reset) => Ok(Idle),
_ => Err(TransitionError::InvalidTransition {
from_stage: "ExecutionState".to_string(),
event: "<exec event>".to_string(),
}),
}
}