| 1 | package moves |
| 2 | |
| 3 | import ( |
| 4 | "strconv" |
| 5 | |
| 6 | "github.com/carlosframework/platform/internal/provision" |
| 7 | ) |
| 8 | |
| 9 | // Transition is what one record write did to a move, as the move log names |
| 10 | // it (log.go): the move, the event, the identity that keys its log object, |
| 11 | // the fields it carries (the regions, the evidence's digests, timings, a |
| 12 | // stuck's role), and the instance incarnation the move's record carried, |
| 13 | // which binds a queued entry to that instance (the console's outbox). The |
| 14 | // box's writers and the console's move pass name their writes with it, so a |
| 15 | // transition has one identity whoever writes it. |
| 16 | type Transition struct { |
| 17 | Op, Event, Identity string |
| 18 | Incarnation string |
| 19 | Fields map[string]string |
| 20 | } |
| 21 | |
| 22 | // phaseOf is the phase a move's state is at: the cut's, the landing's, or |
| 23 | // (rolling back) the target's and the source's. |
| 24 | func phaseOf(m *provision.MoveState) (phase, target, source string) { |
| 25 | switch m.State { |
| 26 | case provision.MoveCutting: |
| 27 | return m.CutPhase, "", "" |
| 28 | case provision.MoveLanding: |
| 29 | return m.LandingPhase, "", "" |
| 30 | case provision.MoveRollingBack: |
| 31 | if m.Rollback != nil { |
| 32 | return "", m.Rollback.TargetPhase, m.Rollback.SourcePhase |
| 33 | } |
| 34 | } |
| 35 | return "", "", "" |
| 36 | } |
| 37 | |
| 38 | // transitionFields are a move's regions, the digests its evidence has |
| 39 | // recorded so far (the source's stop: final TXID, database, files, timers; |
| 40 | // the landing's installed database; the pinned inputs: release, env report) |
| 41 | // and its admitted cut budget. |
| 42 | func transitionFields(m *provision.MoveState) map[string]string { |
| 43 | f := map[string]string{"from": m.From, "to": m.To} |
| 44 | set := func(k, v string) { |
| 45 | if v != "" { |
| 46 | f[k] = v |
| 47 | } |
| 48 | } |
| 49 | if s := m.Source; s != nil { |
| 50 | if s.FinalTXID != 0 { |
| 51 | f["final_txid"] = strconv.FormatUint(s.FinalTXID, 10) |
| 52 | } |
| 53 | set("db_sha256", s.DBSHA256) |
| 54 | set("timers_sha256", s.TimersSHA256) |
| 55 | if s.Files != nil { |
| 56 | set("files_plain", s.Files.Plain) |
| 57 | } |
| 58 | } |
| 59 | if l := m.Landing; l != nil { |
| 60 | set("installed_db_sha256", l.InstalledDBSHA256) |
| 61 | } |
| 62 | if in := m.Inputs; in != nil { |
| 63 | set("release", in.Release) |
| 64 | set("env_report", in.EnvReport) |
| 65 | } |
| 66 | if m.CutBudgetS > 0 { |
| 67 | // The admitted cut's budget, which the member line for it states. |
| 68 | f["cut_budget_s"] = strconv.Itoa(m.CutBudgetS) |
| 69 | } |
| 70 | return f |
| 71 | } |
| 72 | |
| 73 | // seconds is b - a in whole seconds, "" unless both are known. |
| 74 | func seconds(a, b interface{ Unix() int64 }) string { |
| 75 | return strconv.FormatInt(b.Unix()-a.Unix(), 10) |
| 76 | } |
| 77 | |
| 78 | // DeclaredLostIdentity is the identity of a declared loss's entry: the |
| 79 | // rollback's target phase going to lost (TransitionOf), whoever logs it. |
| 80 | const DeclaredLostIdentity = "rolling_back-target-" + provision.RbTargetLost |
| 81 | |
| 82 | // DeclaredLost is the entry of a declared loss of m's target (§7.10), event |
| 83 | // declared_lost, named as TransitionOf names the rollback's target going to |
| 84 | // lost. The console that performs a declaration whose signed consequence is |
| 85 | // that loss names it from the record it read before (a landing, which the |
| 86 | // declaration rolls back, or a rollback whose target is releasing or |
| 87 | // returning), and a box whose pass sees the target lost names it from that |
| 88 | // record. The identity, DeclaredLostIdentity, is the same for both, so |
| 89 | // create-only storage keeps one (final review I4). A target loss is declared |
| 90 | // only on that path, so ok is false for a move in any other state (a |
| 91 | // committed move's destroyed-local-only declaration changes no move state: |
| 92 | // final re-review 1, N1) and for a move with no id. |
| 93 | func DeclaredLost(m *provision.MoveState) (Transition, bool) { |
| 94 | if m == nil || m.ID == "" || (m.State != provision.MoveLanding && m.State != provision.MoveRollingBack) { |
| 95 | return Transition{}, false |
| 96 | } |
| 97 | var rb provision.MoveRollback |
| 98 | if m.Rollback != nil { |
| 99 | rb = *m.Rollback |
| 100 | } |
| 101 | before, after := *m, *m |
| 102 | before.State, after.State = provision.MoveRollingBack, provision.MoveRollingBack |
| 103 | brb, arb := rb, rb |
| 104 | brb.TargetPhase, arb.TargetPhase = "", provision.RbTargetLost |
| 105 | before.Rollback, after.Rollback = &brb, &arb |
| 106 | return TransitionOf(provision.Record{Move: &before}, provision.Record{Move: &after}) |
| 107 | } |
| 108 | |
| 109 | // TransitionOf names the transition from before to after, one record write: |
| 110 | // before as the write found it, after as written. ok is false when the |
| 111 | // write changed nothing the log records (a pin, recovery inputs, a replay). |
| 112 | // |
| 113 | // Identities: <state>-<phase> for a phase step (a rollback names the half |
| 114 | // that moved, rolling_back-target-<p> or rolling_back-source-<p>), the |
| 115 | // flip as cutting-flipped, committed-opened and committed-source_parked, |
| 116 | // reverting-opened, probe_attempt-<n> for the landing's n-th probe, |
| 117 | // stuck-<epoch> keyed by the record's recovery retry epoch, the new state |
| 118 | // itself (requested for preparing, cutting-requested, ready, aborting, |
| 119 | // reverting, relocating, rolling_back), and the terminal outcome (done, |
| 120 | // rolled_back, aborted). A done or rolled_back outcome carries the move's |
| 121 | // timings (Timings) over the journal as the close found it. |
| 122 | func TransitionOf(before, after provision.Record) (Transition, bool) { |
| 123 | bm, am := before.Move, after.Move |
| 124 | if am == nil { |
| 125 | // A close clears the move and leaves its outcome (D11). |
| 126 | if bm == nil || after.LastMove == nil || after.LastMove.ID != bm.ID || bm.ID == "" { |
| 127 | return Transition{}, false |
| 128 | } |
| 129 | f := transitionFields(bm) |
| 130 | if out := after.LastMove.Outcome; out == "done" || out == "rolled_back" { |
| 131 | // The timings (Plan 6 Task 4), from the journal the close |
| 132 | // found: the same for every writer of the entry. |
| 133 | for k, v := range Timings(bm) { |
| 134 | f[k] = timingText(v) |
| 135 | } |
| 136 | } |
| 137 | f["offline_s"] = timingText(after.LastMove.OfflineS) |
| 138 | return Transition{Op: bm.ID, Event: after.LastMove.Outcome, Identity: after.LastMove.Outcome, Incarnation: bm.Incarnation, Fields: f}, true |
| 139 | } |
| 140 | if am.ID == "" || (bm != nil && bm.ID != am.ID) { |
| 141 | return Transition{}, false |
| 142 | } |
| 143 | e := Transition{Op: am.ID, Incarnation: am.Incarnation, Fields: transitionFields(am)} |
| 144 | if bm == nil { |
| 145 | bm = &provision.MoveState{} |
| 146 | } |
| 147 | switch { |
| 148 | case am.State == provision.MoveStuck: |
| 149 | if bm.State == provision.MoveStuck { |
| 150 | return Transition{}, false |
| 151 | } |
| 152 | e.Event, e.Identity = "stuck", "stuck-"+strconv.FormatUint(am.RecoveryRetryEpoch, 10) |
| 153 | // A rollback's target stops for an operator at its return |
| 154 | // (returning) and at its release (releasing, whose files cannot be |
| 155 | // archived: final review M1); every other stuck is the source's. |
| 156 | e.Fields["role"] = "source" |
| 157 | if rb := am.Rollback; rb != nil && (rb.TargetPhase == provision.RbTargetReturning || |
| 158 | rb.TargetPhase == provision.RbTargetReleasing && am.StuckReason == provision.StuckReleaseTargetFiles) { |
| 159 | e.Fields["role"] = "target" |
| 160 | } |
| 161 | if am.StuckReason != "" { |
| 162 | e.Fields["reason"] = am.StuckReason |
| 163 | } |
| 164 | return e, true |
| 165 | case am.State == provision.MoveLanding && am.Landing != nil && am.Landing.Attempts > 0 && (bm.Landing == nil || am.Landing.Attempts > bm.Landing.Attempts): |
| 166 | e.Event, e.Identity = "probe_attempt", "probe_attempt-"+strconv.Itoa(am.Landing.Attempts) |
| 167 | return e, true |
| 168 | case bm.State == provision.MoveCutting && am.State == provision.MoveLanding: |
| 169 | e.Event, e.Identity = "flipped", "cutting-flipped" |
| 170 | return e, true |
| 171 | case am.State == provision.MoveCommitted && bm.State == provision.MoveCommitted: |
| 172 | switch { |
| 173 | case am.SourceParkedAt != nil && bm.SourceParkedAt == nil: |
| 174 | e.Event, e.Identity = "source_parked", "committed-source_parked" |
| 175 | case am.OpenedAt != nil && bm.OpenedAt == nil: |
| 176 | e.Event, e.Identity = "opened", "committed-opened" |
| 177 | if am.CutAt != nil { |
| 178 | e.Fields["offline_s"] = seconds(*am.CutAt, *am.OpenedAt) |
| 179 | } |
| 180 | default: |
| 181 | return Transition{}, false |
| 182 | } |
| 183 | return e, true |
| 184 | case am.State == provision.MoveReverting && bm.State == provision.MoveReverting: |
| 185 | if am.ReopenedAt == nil || bm.ReopenedAt != nil { |
| 186 | return Transition{}, false |
| 187 | } |
| 188 | e.Event, e.Identity = "rev_opened", "reverting-opened" |
| 189 | if am.CutAt != nil { |
| 190 | e.Fields["offline_s"] = seconds(*am.CutAt, *am.ReopenedAt) |
| 191 | } |
| 192 | return e, true |
| 193 | } |
| 194 | phase, target, source := phaseOf(am) |
| 195 | bphase, btarget, bsource := phaseOf(bm) |
| 196 | if am.State == bm.State { |
| 197 | switch { |
| 198 | case am.State == provision.MoveRollingBack && target != btarget: |
| 199 | e.Event, e.Identity = target, "rolling_back-target-"+target |
| 200 | if target == provision.RbTargetLost { |
| 201 | e.Event = "declared_lost" |
| 202 | } |
| 203 | case am.State == provision.MoveRollingBack && source != bsource: |
| 204 | e.Event, e.Identity = source, "rolling_back-source-"+source |
| 205 | rb := am.Rollback |
| 206 | switch source { |
| 207 | case provision.RbSourceRecovered: |
| 208 | if rb.RecoveredAt != nil { |
| 209 | if rb.RequestedAt != nil { |
| 210 | e.Fields["recovery_s"] = seconds(*rb.RequestedAt, *rb.RecoveredAt) |
| 211 | } |
| 212 | if am.CutAt != nil { |
| 213 | e.Fields["offline_s"] = seconds(*am.CutAt, *rb.RecoveredAt) |
| 214 | } |
| 215 | } |
| 216 | case provision.RbSourceOpened: |
| 217 | if rb.OpenedAt != nil && am.CutAt != nil { |
| 218 | e.Fields["offline_s"] = seconds(*am.CutAt, *rb.OpenedAt) |
| 219 | } |
| 220 | } |
| 221 | case phase != bphase && phase != "": |
| 222 | e.Event, e.Identity = phase, am.State+"-"+phase |
| 223 | if am.State == provision.MoveCutting && phase == provision.CutRequested { |
| 224 | e.Event = "cut_requested" |
| 225 | } |
| 226 | default: |
| 227 | return Transition{}, false |
| 228 | } |
| 229 | return e, true |
| 230 | } |
| 231 | // A new state. |
| 232 | switch am.State { |
| 233 | case provision.MovePreparing: |
| 234 | e.Event, e.Identity = "requested", "requested" |
| 235 | case provision.MoveCutting: |
| 236 | e.Event, e.Identity = phase, "cutting-"+phase |
| 237 | if phase == provision.CutRequested || phase == "" { |
| 238 | e.Event, e.Identity = "cut_requested", "cutting-requested" |
| 239 | } |
| 240 | case provision.MoveLanding: |
| 241 | e.Event, e.Identity = phase, "landing-"+phase |
| 242 | case provision.MoveRollingBack: |
| 243 | e.Event, e.Identity = "rolling_back", "rolling_back" |
| 244 | if am.Rollback != nil && am.Rollback.Reason != "" { |
| 245 | e.Fields["reason"] = am.Rollback.Reason |
| 246 | } |
| 247 | default: |
| 248 | // ready, committed, aborting, reverting, relocating: the state is the |
| 249 | // event. |
| 250 | e.Event, e.Identity = am.State, am.State |
| 251 | } |
| 252 | return e, true |
| 253 | } |
| 254 | |
amadan