| 1 | package hostresolve |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "encoding/json" |
| 6 | |
| 7 | "github.com/carlosframework/platform/internal/hostclaim" |
| 8 | "github.com/carlosframework/platform/internal/hostfence" |
| 9 | ) |
| 10 | |
| 11 | // OperationOwner supplies operation policy. The service owns challenge signing, |
| 12 | // acceptance, quarantine and the durable prepared/committed loss sequence. |
| 13 | // InspectLoss and LossWriteSources are read-only. PrepareLoss journals the |
| 14 | // operation's decision before claim revocation; FinishLoss releases only what |
| 15 | // the committed declaration permits. Both hooks must be idempotent. Retry |
| 16 | // dispatch uses the accepted loss's kind, even after the current kind changes. |
| 17 | // Callbacks receive detached values and must guard every external write. |
| 18 | // PrepareLoss can arrive after a concurrent FinishLoss or after the loss is |
| 19 | // conflicted. Its conditional record write must never regress a later state; |
| 20 | // it must not write the claim or treat its journal as execution authority. |
| 21 | // A prepared record is inert until both the claim loss reference and committed |
| 22 | // loss record exist. FinishLoss can observe a successor holder or operation: |
| 23 | // it derives effects from the signed loss, refuses mismatched identities, and |
| 24 | // treats its own durable completion as success without touching the successor. |
| 25 | type OperationOwner interface { |
| 26 | InspectLoss(context.Context, hostclaim.Observed, hostfence.RecordObservation, string) (hostfence.Consequences, hostclaim.LossConsequences, error) |
| 27 | LossWriteSources(context.Context, hostclaim.Observed, hostclaim.LossConsequences) ([]hostclaim.WriteSource, error) |
| 28 | hostclaim.LossOperationOwner |
| 29 | PrepareLoss(context.Context, hostclaim.Observed, hostclaim.LossRecord) error |
| 30 | FinishLoss(context.Context, hostclaim.Observed, hostclaim.LossRecord) error |
| 31 | } |
| 32 | |
| 33 | func (s Service) operationOwner(kind string) (OperationOwner, error) { |
| 34 | switch kind { |
| 35 | case hostclaim.KindServing, hostclaim.KindParking, hostclaim.KindDeleting: |
| 36 | return builtinOwner{}, nil |
| 37 | case hostclaim.KindMoving, hostclaim.KindLanding, hostclaim.KindReverting, hostclaim.KindRestoring: |
| 38 | if owner := s.Owners[kind]; owner != nil { |
| 39 | return owner, nil |
| 40 | } |
| 41 | } |
| 42 | return nil, ErrResolve |
| 43 | } |
| 44 | |
| 45 | type builtinOwner struct{ owner } |
| 46 | |
| 47 | func (builtinOwner) InspectLoss(_ context.Context, o hostclaim.Observed, _ hostfence.RecordObservation, box string) (hostfence.Consequences, hostclaim.LossConsequences, error) { |
| 48 | return effects(o.Claim, box) |
| 49 | } |
| 50 | func (builtinOwner) LossWriteSources(context.Context, hostclaim.Observed, hostclaim.LossConsequences) ([]hostclaim.WriteSource, error) { |
| 51 | return nil, nil |
| 52 | } |
| 53 | func (builtinOwner) PrepareLoss(context.Context, hostclaim.Observed, hostclaim.LossRecord) error { |
| 54 | return nil |
| 55 | } |
| 56 | func (builtinOwner) FinishLoss(context.Context, hostclaim.Observed, hostclaim.LossRecord) error { |
| 57 | return nil |
| 58 | } |
| 59 | |
| 60 | func detached[T any](v T) (T, error) { |
| 61 | var out T |
| 62 | wire, err := json.Marshal(v) |
| 63 | if err == nil { |
| 64 | err = json.Unmarshal(wire, &out) |
| 65 | } |
| 66 | return out, err |
| 67 | } |
| 68 | |
| 69 | func inspectOwner(ctx context.Context, owner OperationOwner, o hostclaim.Observed, record hostfence.RecordObservation, box string) (hostfence.Consequences, hostclaim.LossConsequences, error) { |
| 70 | copy, err := detached(o) |
| 71 | if err != nil { |
| 72 | return hostfence.Consequences{}, hostclaim.LossConsequences{}, err |
| 73 | } |
| 74 | shown, actual, err := owner.InspectLoss(ctx, copy, record, box) |
| 75 | if err != nil { |
| 76 | return shown, actual, err |
| 77 | } |
| 78 | shown, err = detached(shown) |
| 79 | if err != nil { |
| 80 | return shown, actual, err |
| 81 | } |
| 82 | actual, err = detached(actual) |
| 83 | return shown, actual, err |
| 84 | } |
| 85 | |
| 86 | func ownerSources(ctx context.Context, owner OperationOwner, o hostclaim.Observed, actual hostclaim.LossConsequences) ([]hostclaim.WriteSource, error) { |
| 87 | copy, err := detached(o) |
| 88 | if err != nil { |
| 89 | return nil, err |
| 90 | } |
| 91 | effects, err := detached(actual) |
| 92 | if err != nil { |
| 93 | return nil, err |
| 94 | } |
| 95 | sources, err := owner.LossWriteSources(ctx, copy, effects) |
| 96 | if err != nil { |
| 97 | return nil, err |
| 98 | } |
| 99 | return detached(sources) |
| 100 | } |
| 101 | |
| 102 | func ownerHook(ctx context.Context, owner OperationOwner, o hostclaim.Observed, loss hostclaim.LossRecord, finish bool) error { |
| 103 | copy, err := detached(o) |
| 104 | if err != nil { |
| 105 | return err |
| 106 | } |
| 107 | record, err := detached(loss) |
| 108 | if err != nil { |
| 109 | return err |
| 110 | } |
| 111 | if finish { |
| 112 | return owner.FinishLoss(ctx, copy, record) |
| 113 | } |
| 114 | return owner.PrepareLoss(ctx, copy, record) |
| 115 | } |
| 116 | |
amadan