Files
app/backend/app/api/routes/observability.py
T
stroblme 857a5a57d8 Health: a flow that cannot run says so, and the brain marks which neurons
A dependency loop is flagged on the canvas and was invisible everywhere else:
/observability/summary answered "ok" with an empty problems list while the
published flow could not run at all. It now reports the flows validation
blocks, and the brain graph carries the reason on each neuron the issue names
so the view built to find broken wiring can show it.

Node errors stay counted once, as the nodes that failed to load, and an
advisory like an unauthenticated webhook marks nothing — it is worth saying,
but the flow still runs.
2026-08-17 14:39:07 +02:00

355 lines
11 KiB
Python

"""What the engine has been doing: health now, and history since.
The live state comes from the controller; everything older than the websocket's
memory comes from the rollups the metrics collector writes. Deliberately not
built on ``/utils/health/``: that endpoint answers 503 when something is wrong,
which the generated SDK turns into a thrown error — and a health page that
cannot render while the engine is degraded is the wrong way round.
"""
from datetime import datetime, timedelta, timezone
from typing import Any, Literal
from fastapi import APIRouter, Depends, Request
from fastapi.concurrency import run_in_threadpool
from pydantic import BaseModel
from sqlalchemy import func
from sqlmodel import col, select
from app.api.deps import FlowControllerDep, SessionDep, get_current_user
from app.flow.controller import ADVISORY_ISSUES, NodeStatus
from app.models import EngineEvent, FlowRun, MetricBucket
router = APIRouter(
prefix="/observability",
tags=["observability"],
dependencies=[Depends(get_current_user)],
)
#: How many slices a per-flow sparkline is folded into.
SPARK_SLICES = 60
class HealthSummary(BaseModel):
status: str
problems: list[str]
flows: dict[str, int]
nodes: dict[str, int]
queue: dict[str, Any]
loop_lag: dict[str, float]
failures_24h: int
class SeriesPoint(BaseModel):
ts: float
executions: int
errors: int
messages: int
avg_ms: float
max_ms: float
avg_lag_ms: float
class FlowRollup(BaseModel):
flow: str
executions: int
errors: int
messages: int
avg_ms: float
avg_lag_ms: float
spark: list[int]
last_error_ts: float | None = None
class RunRow(BaseModel):
id: str
flow: str
source: str
status: str
started_at: datetime
finished_at: datetime | None = None
nodes: int
errors: int
duration_ms: float
deliveries: int
class EventRow(BaseModel):
id: int
ts: datetime
type: str
flow: str
node: str
detail: str
actor: str
class DeadLetter(BaseModel):
id: str
ts: float
flow: str
node: str
cause: str
reason: str
def _since(hours: int) -> datetime:
return datetime.now(timezone.utc) - timedelta(hours=hours)
def _aware(when: datetime) -> datetime:
"""A bound as the columns store it. A naive one is read as UTC."""
return when if when.tzinfo else when.replace(tzinfo=timezone.utc)
@router.get("/summary", response_model=HealthSummary)
async def read_summary(
request: Request, controller: FlowControllerDep, session: SessionDep
) -> Any:
"""How the engine is doing right now. Always 200, degraded or not."""
watchdog = getattr(request.app.state, "watchdog", None)
problems: list[str] = []
if watchdog is not None and watchdog.degraded:
problems.append("event loop lagging")
queue = await run_in_threadpool(controller.queue_stats)
if queue.get("oldest_pending_s", 0) > 120:
problems.append("queue stalled")
if queue.get("error"):
problems.append("work queue unreachable")
names = await run_in_threadpool(controller.store.list_flows)
quarantined = controller.quarantined
paused = set(controller.paused_flows())
entries = list(controller.loaded.values())
errored = [e for e in entries if e.status is NodeStatus.ERROR]
if quarantined:
problems.append(f"{len(quarantined)} flow(s) quarantined")
if errored:
problems.append(f"{len(errored)} node(s) failed to load")
# What the canvas flags on a flow — a dependency loop, an input nothing
# feeds — stops that flow running just as surely as a node that will not
# load, and until now this screen was the one place it did not show.
# `node_error` is left out: those are the nodes already counted above.
invalid = sorted(
{
issue.flow
for issue in controller.issues
if issue.flow
and issue.code != "node_error"
and issue.code not in ADVISORY_ISSUES
}
)
if invalid:
problems.append(f"{len(invalid)} flow(s) cannot run: {', '.join(invalid)}")
statement = (
select(func.count())
.select_from(EngineEvent)
.where(col(EngineEvent.ts) >= _since(24), col(EngineEvent.type) != "audit")
)
# The health page polls this every ten seconds; the driver is synchronous.
failures = await run_in_threadpool(lambda: session.exec(statement).one())
return HealthSummary(
status="degraded" if problems else "ok",
problems=problems,
flows={
"total": len(names),
"running": len(
[n for n in names if controller.is_enabled(n) and n not in quarantined]
),
"paused": len(paused),
"quarantined": len(quarantined),
"invalid": len(invalid),
},
nodes={"total": len(entries), "error": len(errored)},
queue=queue,
loop_lag=(
watchdog.snapshot()
if watchdog is not None
else {"ewma": 0.0, "max_60s": 0.0}
),
failures_24h=int(failures),
)
@router.get("/timeseries", response_model=list[SeriesPoint])
def read_timeseries(
session: SessionDep,
flow: str | None = None,
node: str | None = None,
hours: int = 24,
bucket_s: int = 60,
) -> Any:
"""Executions, errors and timings over time, summed across nodes."""
# ponytail: the fold is in Python — a day is at most 1440 rows per node.
# date_bin() if the window ever grows past that.
statement = select(MetricBucket).where(col(MetricBucket.bucket) >= _since(hours))
if flow:
statement = statement.where(col(MetricBucket.flow) == flow)
if node:
statement = statement.where(col(MetricBucket.node) == node)
slices: dict[float, dict[str, float]] = {}
for row in session.exec(statement.order_by(col(MetricBucket.bucket))):
stamp = row.bucket.timestamp()
key = stamp - stamp % max(60, bucket_s)
point = slices.setdefault(
key,
{
"executions": 0.0,
"errors": 0.0,
"messages": 0.0,
"duration_sum_ms": 0.0,
"max_ms": 0.0,
"lag_sum_ms": 0.0,
"items": 0.0,
},
)
point["executions"] += row.executions
point["errors"] += row.errors
point["messages"] += row.messages
point["duration_sum_ms"] += row.duration_sum_ms
point["max_ms"] = max(point["max_ms"], row.duration_max_ms)
point["lag_sum_ms"] += row.lag_sum_ms
point["items"] += row.items
return [
SeriesPoint(
ts=ts,
executions=int(point["executions"]),
errors=int(point["errors"]),
messages=int(point["messages"]),
avg_ms=round(point["duration_sum_ms"] / (point["executions"] or 1), 2),
max_ms=round(point["max_ms"], 2),
avg_lag_ms=round(point["lag_sum_ms"] / (point["items"] or 1), 2),
)
for ts, point in sorted(slices.items())
]
@router.get("/flows", response_model=list[FlowRollup])
def read_flow_rollups(session: SessionDep, hours: int = 24) -> Any:
"""One row per flow, with a coarse trend of how much it ran."""
since = _since(hours)
window = hours * 3600
start = since.timestamp()
rollups: dict[str, dict[str, Any]] = {}
for row in session.exec(
select(MetricBucket).where(col(MetricBucket.bucket) >= since)
):
entry = rollups.setdefault(
row.flow,
{
"executions": 0,
"errors": 0,
"messages": 0,
"duration_sum_ms": 0.0,
"lag_sum_ms": 0.0,
"items": 0,
"spark": [0] * SPARK_SLICES,
},
)
entry["executions"] += row.executions
entry["errors"] += row.errors
entry["messages"] += row.messages
entry["duration_sum_ms"] += row.duration_sum_ms
entry["lag_sum_ms"] += row.lag_sum_ms
entry["items"] += row.items
slot = min(
SPARK_SLICES - 1,
max(0, int((row.bucket.timestamp() - start) / window * SPARK_SLICES)),
)
entry["spark"][slot] += row.executions
# `.all()` first: a Result has `keys()`, so dict() would read it as a
# mapping and subscript it.
last_errors = dict(
session.exec(
select(col(EngineEvent.flow), func.max(col(EngineEvent.ts)))
.where(col(EngineEvent.type) == "node_error", col(EngineEvent.ts) >= since)
.group_by(col(EngineEvent.flow))
).all()
)
return [
FlowRollup(
flow=flow,
executions=entry["executions"],
errors=entry["errors"],
messages=entry["messages"],
avg_ms=round(entry["duration_sum_ms"] / (entry["executions"] or 1), 2),
avg_lag_ms=round(entry["lag_sum_ms"] / (entry["items"] or 1), 2),
spark=entry["spark"],
last_error_ts=(
last_errors[flow].timestamp() if flow in last_errors else None
),
)
for flow, entry in sorted(rollups.items())
]
@router.get("/runs", response_model=list[RunRow])
def read_runs(
session: SessionDep,
flow: str | None = None,
status: str | None = None,
since: datetime | None = None,
until: datetime | None = None,
limit: int = 50,
) -> Any:
"""Recent cascades, newest first.
``since`` is inclusive and ``until`` exclusive, so a window of one minute
holds exactly the runs of the minute bucket the charts are drawn from.
"""
statement = select(FlowRun).order_by(col(FlowRun.started_at).desc())
if flow:
statement = statement.where(col(FlowRun.flow) == flow)
if status:
statement = statement.where(col(FlowRun.status) == status)
if since:
statement = statement.where(col(FlowRun.started_at) >= _aware(since))
if until:
statement = statement.where(col(FlowRun.started_at) < _aware(until))
return list(session.exec(statement.limit(min(limit, 200))))
@router.get("/events", response_model=list[EventRow])
def read_events(
session: SessionDep,
kind: Literal["failure", "audit"] = "failure",
flow: str | None = None,
since: datetime | None = None,
until: datetime | None = None,
limit: int = 100,
) -> Any:
"""What went wrong, or who changed what. Newest first.
``since`` is inclusive and ``until`` exclusive, the same window ``/runs``
takes, so a list can cover the span the charts beside it are drawn from.
"""
statement = select(EngineEvent).order_by(col(EngineEvent.ts).desc())
if kind == "audit":
statement = statement.where(col(EngineEvent.type) == "audit")
else:
statement = statement.where(col(EngineEvent.type) != "audit")
if flow:
statement = statement.where(col(EngineEvent.flow) == flow)
if since:
statement = statement.where(col(EngineEvent.ts) >= _aware(since))
if until:
statement = statement.where(col(EngineEvent.ts) < _aware(until))
return list(session.exec(statement.limit(min(limit, 500))))
@router.get("/dead-letter", response_model=list[DeadLetter])
async def read_dead_letters(controller: FlowControllerDep, limit: int = 50) -> Any:
"""Work the engine gave up on, which nothing else surfaces."""
if controller.execution is None:
return []
return await run_in_threadpool(controller.execution.queue.dead_letters, limit)