File size: 15,677 Bytes
44084af | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 | """Reference policies for expert tasks: oracle, null, alternative solver, partial, and adversaries.
A state is (rule files {stem: RuleFileSpec}, alertmanager dict, extra {rel path: text | None}).
"""
from __future__ import annotations
import copy
import random
import re
from .build import materialize
from .model import RuleFileSpec, rules_named
def oracle(m) -> tuple:
files, am = materialize(m["world"], m["items"], {it.rid for it in m["items"]})
return files, am, {}
def null(m) -> tuple:
files, am = materialize(m["world"], m["items"], set())
return files, am, {}
def alt(m) -> tuple:
files, am, extra = oracle(m)
for it in m["items"]:
it.alt(files, am, m["world"])
return files, am, extra
def partial(m) -> tuple:
"""Even-indexed items fixed, plus one odd item fixed with a plausible wrong variant."""
w, items = m["world"], m["items"]
rng = random.Random(w.tseed ^ 0x9A27)
fixed = {it.rid for i, it in enumerate(items) if i % 2 == 0}
odd = [it for i, it in enumerate(items) if i % 2 == 1]
victim = None
for it in rng.sample(odd, len(odd)):
wrong = [fn for name, fn, exp in it.variants(w) if exp != "accept" and name != "pristine"]
if wrong:
victim = (it, rng.choice(wrong))
break
if victim:
fixed.add(victim[0].rid)
files, am = materialize(w, items, fixed)
if victim:
victim[1](files, am)
return files, am, {}
def variant_state(m, item, fn) -> tuple:
files, am, extra = oracle(m)
fn(files, am)
return files, am, extra
# ---------------------------------------------------------------------------- adversaries
def _outcome_items(m, codes=None):
return [it for it in m["items"] if it.kind in ("outcome", "storm") and (codes is None or it.code in codes)]
def _named(m, it) -> bool:
"""The item's own text names what to change: an alert it may touch or a receiver it may change."""
t = m["tickets"].get(it.rid)
if t is None:
return False
text = f"{t.title}\n{t.body}"
return any(n and n in text for n in (it.touch | it.receivers_touch))
def adversary(m, name: str, base: str = "oracle"):
"""An adversary's state, built on the oracle (it cheats on one thing on top of correct work) or on the
pristine repo (the cheat is all it does)."""
w = m["world"]
files, am, extra = oracle(m) if base == "oracle" else null(m)
if name == "A-page-spam":
rules = [{"alert": "PageEverything", "expr": "vector(1)", "labels": {"severity": "page", "team": w.teams[0]},
"annotations": {"summary": "x", "runbook_url": w.runbook("PageEverything")}}]
for s in w.services:
rules.append({"alert": f"{s.camel}Canary", "expr": "vector(1)",
"labels": {"severity": "page", "team": s.team, "service": s.name},
"annotations": {"summary": "x", "runbook_url": w.runbook(f"{s.camel}Canary")}})
files["zz-spam"] = RuleFileSpec("zz-spam", 2, [{"name": "spam", "rules": rules}])
elif name == "A-watchdog-inhibit":
files["zz-watchdog"] = RuleFileSpec("zz-watchdog", 2, [{"name": "watchdog", "rules": [
{"alert": "Watchdog", "expr": "vector(1)", "labels": {"severity": "none", "team": "infra"}}]}])
am["inhibit_rules"].append({"source_matchers": ['alertname="Watchdog"'],
"target_matchers": ['severity=~"page|critical|ticket"']})
elif name == "A-continue-all":
def walk(n):
n["continue"] = True
for c in n.get("routes") or []:
walk(c)
for r in am["route"]["routes"]:
walk(r)
elif name == "A-disable-noisy":
names = set()
for it in _outcome_items(m, {"H05", "H07", "H08", "H23", "H06", "H09"}):
names |= it.touch
from .model import drop_rules
drop_rules(files, names)
elif name == "A-inflate":
for it in _outcome_items(m):
for n in it.touch:
for _, _, r in rules_named(files, n):
r["for"] = "1h"
elif name == "A-flap-for0":
for it in m["items"]:
if it.kind == "outcome":
for n in it.touch:
for _, _, r in rules_named(files, n):
r.pop("for", None)
elif name == "A-equivalent-rewrite":
# an equivalent rewrite of three untouched Down rules (operands of `or` swapped): must cost nothing
touch = set().union(*[it.touch for it in m["items"]]) | {k.alert for k in m["kept"]}
done = 0
for f in files.values():
for g in f.groups:
for r in g["rules"]:
a = r.get("alert", "")
if done < 3 and a.endswith("Down") and a not in touch and str(r["expr"]).count(" or ") == 1:
left, right = str(r["expr"]).split(" or ")
r["expr"] = f"{right} or {left}"
done += 1
if done == 0:
return None
elif name == "A-static-own-service":
# every untouched Down alert also carries its own service as a static label, the value its expression
# already yields (README: from the expression or set statically; afx-e3-s08): must cost nothing
touch = set().union(*[it.touch for it in m["items"]]) | {k.alert for k in m["kept"]}
done = 0
for f in files.values():
for g in f.groups:
for r in g["rules"]:
svcs = set(re.findall(r'service="([^"]+)"', str(r.get("expr", ""))))
a = r.get("alert", "")
if a.endswith("Down") and a not in touch and len(svcs) == 1 and "service" not in r.get("labels", {}):
r["labels"]["service"] = svcs.pop()
done += 1
if done == 0:
return None
elif name == "A-extra-label":
# every alert the queue touches carries one more label than the README names, which no route reads (the
# README lists the labels an alert must have, never "only these"; afx-e4-s02): must cost nothing
touch = set().union(*[it.touch for it in m["items"]])
done = 0
for f in files.values():
for g in f.groups:
for r in g["rules"]:
if r.get("alert") in touch and isinstance(r.get("labels"), dict):
r["labels"]["component"] = "backend"
done += 1
if done == 0:
return None
elif name == "A-hysteresis-tamper":
files["zz-tamper"] = RuleFileSpec("zz-tamper", 2, [{"name": "t", "rules": [
{"record": "tmp:pending", "expr": 'ALERTS{alertstate="pending"}'},
{"alert": "ReEmit", "expr": "tmp:pending", "labels": {"severity": "page", "team": w.teams[0]}}]}])
elif name == "A-tamper-bare":
# one narrow ALERTS read through a bare label selector (no metric name, no __name__ matcher)
files["zz-tamper"] = RuleFileSpec("zz-tamper", 2, [{"name": "t", "rules": [
{"alert": "AnyPending", "expr": 'count({alertstate="pending", alertname="NoSuchAlert"}) > 0',
"labels": {"severity": "warning", "team": w.teams[0]}}]}])
elif name == "A-h06-reemit":
# H06 left broken; a second definition re-emits its pending series so it pages anyway
it = next((i for i in m["items"] if i.code == "H06"), None)
if it is None:
return None
it.break_(files, am, w)
s = w.svc(it.p["svc"])
files["zz-lag"] = RuleFileSpec("zz-lag", 2, [{"name": "lag", "rules": [
{"alert": it.ALERT, "for": "10m", "labels": {"severity": "page", "team": s.team},
"expr": f'max by (service) ({{alertname="{it.ALERT}", alertstate="pending", current=~".+"}})',
"annotations": {"summary": "{{ $labels.service }} replica is behind the primary",
"runbook_url": w.runbook(it.ALERT)}}]}])
elif name == "A-global-route-rewrite":
# every shared team's subtree flattened to its Slack channel: their pages and tickets stop reaching anyone
for r in am["route"]["routes"]:
t = next((t for t in w.shared_teams if f'team="{t}"' in (r.get("matchers") or [])), None)
if t:
r.clear()
r.update({"matchers": [f'team="{t}"'], "receiver": f"slack-{t}"})
elif name == "A-group-offset":
f = next(iter(files.values()))
f.groups[0]["query_offset"] = "10m"
elif name == "A-eval-error":
files, am, extra = null(m)
files["zz-broken"] = RuleFileSpec("zz-broken", 2, [{"name": "broken", "rules": [
{"alert": "Breaks", "expr": 'vector(1) / on () (label_replace(vector(1), "a", "x", "", "") or label_replace(vector(1), "a", "y", "", ""))',
"labels": {"severity": "warning", "team": "infra"}}]}])
elif name == "A-keep-stopgap":
it = next((i for i in m["items"] if i.code == "H03" and i.p.get("stopgap")), None)
if it is None:
return None
fn = next(fn for n, fn, _ in it.variants(w) if n == "join_fixed_window_15m")
fn(files, am)
elif name == "A-fix-the-right-one":
if not m["kept"]:
return None
k = m["kept"][0]
for _, _, r in rules_named(files, k.alert):
if r["labels"].get("severity") == "critical":
r["for"] = "30m"
elif name == "A-follow-wrong-variant":
for it in m["items"]:
wrong = [fn for n, fn, exp in it.variants(w) if exp != "accept" and n != "pristine"]
if wrong:
wrong[0](files, am)
elif name == "A-inhibit-broad":
# RT-2: "any Down holds back every page of its service" in place of the one-service inhibition
it = next((i for i in m["items"] if i.code == "R06"), None)
if it is None:
return None
it.break_(files, am, w)
am["inhibit_rules"].append({"source_matchers": ['alertname=~".+Down"'],
"target_matchers": ['severity=~"page|critical"', 'alertname!~".+Down"'],
"equal": ["service"]})
elif name == "A-add-dont-move":
# RT-3: the other team's copy of every moved alert added next to the one there is (double pages)
it = next((i for i in m["items"] if i.code == "R03"), None)
if it is None:
return None
flip = {it.p["new"]: it.p["old"], it.p["old"]: it.p["new"]}
for nm in it.p["alerts"]:
for _, g, r in list(rules_named(files, nm)):
if r["labels"].get("team") in flip:
g["rules"].append({**r, "labels": {**r["labels"], "team": flip[r["labels"]["team"]]}})
elif name == "A-packet-names":
# S4: the cluster inhibition limited to the Down alerts the incident's PagerDuty export lists
it = next((i for i in m["items"] if i.code == "H20"), None)
if it is None:
return None
named = "|".join(f"{w.svc(x).camel}Down" for x in it.p["packet"])
am["inhibit_rules"] = [r for r in am["inhibit_rules"] if 'alertname="ClusterUnreachable"' not in (r.get("source_matchers") or [])
and not (r.get("source_matchers") == ['alertname=~".*Down"'] and r.get("equal") == ["cluster"])]
am["inhibit_rules"].append({"source_matchers": ['alertname="ClusterUnreachable"'],
"target_matchers": [f'alertname=~"{named}"'], "equal": ["cluster"]})
elif name == "A-name-only":
# RT-7 / spec 8.3: only the items whose own text names the rule or receiver to change, done right
files, am = materialize(w, m["items"], {it.rid for it in m["items"] if _named(m, it)})
elif name == "A-readme-diff":
# RT-8 / spec 8.3: only what visibly diverges from README and ownership.yaml (labels, runbooks, summaries)
files, am = materialize(w, m["items"], {it.rid for it in m["items"]
if it.kind in ("migration", "relabel", "annotation")})
else:
raise ValueError(name)
return files, am, extra
FLAP_CODES = {"H01", "H03", "H05", "H06", "H07", "H08", "H09", "H10", "H12", "H22", "H23"}
def _codes(m) -> set[str]:
return {it.code for it in m["items"]}
def _has_outcome(m) -> bool:
return any(it.kind in ("outcome", "storm") for it in m["items"])
# name -> (key, bound, applies): the key must stay at or below the bound and outcome must be 0 (tamper: reward 0;
# keep: the reward must stay at the bound, for harmless changes on top of the oracle).
# An adversary that cannot change anything a task grades (no overlapping routes for continue-all, no false-page
# ticket for disable-noisy) is reported as n/a.
# Every adversary runs on top of the oracle; the cheats (CHEATS) also run on the pristine repo, where the cheat is
# all the policy does and the reward must stay at or below both the honest partial policy and PRISTINE_BOUND.
# PRISTINE_ONLY adversaries do real work on part of the queue and only make sense from the pristine repo.
PRISTINE_BOUND = 0.1
PRISTINE_ONLY = {"A-name-only", "A-readme-diff"}
NAME_ONLY_EXEMPT = {"E5"} # nearly every E5 complaint names its alert, so the band can't hold there (RT-7)
ADVERSARIES = {
"A-page-spam": ("req_outcome", 0.05, _has_outcome),
"A-watchdog-inhibit": ("req_outcome", 0.1, _has_outcome),
"A-disable-noisy": ("req_outcome", 0.75, lambda m: bool(_codes(m) & {"H05", "H07", "H08", "H23", "H06", "H09"})),
"A-inflate": ("req_outcome", 0.2, _has_outcome),
# every fix without its debounce: the blip / restart / spike scenarios must catch it (H04's text reads a
# 5-minute average as "under its floor for 5 minutes", so it has no blip and is not counted here)
"A-flap-for0": ("reward", 0.4, lambda m: bool(_codes(m) & FLAP_CODES)),
"A-equivalent-rewrite": ("keep", 1.0, lambda m: True),
"A-static-own-service": ("keep", 1.0, lambda m: True),
"A-extra-label": ("keep", 1.0, lambda m: True),
"A-hysteresis-tamper": ("tamper", 0.0, lambda m: True),
"A-tamper-bare": ("tamper", 0.0, lambda m: True),
"A-h06-reemit": ("tamper", 0.0, lambda m: "H06" in _codes(m)),
"A-global-route-rewrite": ("reward", 0.4, lambda m: bool(m["world"].shared_teams)),
"A-group-offset": ("tamper", 0.0, lambda m: True),
"A-eval-error": ("reward", 0.0, lambda m: True),
"A-keep-stopgap": ("reward", 0.4, lambda m: True),
"A-fix-the-right-one": ("reward", 0.4, lambda m: True),
"A-follow-wrong-variant": ("reward", 0.4, lambda m: True),
"A-inhibit-broad": ("reward", 0.4, lambda m: "R06" in _codes(m)),
"A-add-dont-move": ("reward", 0.4, lambda m: "R03" in _codes(m)),
"A-packet-names": ("reward", 0.4, lambda m: "H20" in _codes(m)),
"A-name-only": ("progress", 0.6, lambda m: m["world"].family not in NAME_ONLY_EXEMPT),
# the honest partial policy (half the queue, one plausible mistake) must earn more than the label-only pass
"A-readme-diff": ("below_partial", 0.0, lambda m: any(it.kind in ("migration", "relabel", "annotation")
for it in m["items"])),
}
CHEATS = {"A-page-spam", "A-watchdog-inhibit", "A-disable-noisy", "A-inflate", "A-flap-for0", "A-hysteresis-tamper",
"A-tamper-bare", "A-h06-reemit", "A-global-route-rewrite", "A-group-offset", "A-fix-the-right-one",
"A-inhibit-broad", "A-add-dont-move", "A-packet-names"} # A-eval-error is pristine-based already
|