| 1 | package abono |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "errors" |
| 6 | "fmt" |
| 7 | |
| 8 | "gorm.io/gorm" |
| 9 | |
| 10 | "amadan.net/rastrillo/abono/internal/stripeapi" |
| 11 | ) |
| 12 | |
| 13 | // Report is what a Reconcile looked at. When Reconcile also returns an |
| 14 | // error, the Report says what was done all the same: the subscriptions |
| 15 | // that synced (Subscriptions - Failed of them) are committed, so a page |
| 16 | // must not say that nothing was synced when that is more than none. |
| 17 | type Report struct { |
| 18 | // Subscriptions is how many Stripe subscriptions were listed and |
| 19 | // synced, or tried. |
| 20 | Subscriptions int |
| 21 | // Failed is how many of them could not be synced. |
| 22 | Failed int |
| 23 | // Subjects is how many subjects OnChange was run for. |
| 24 | Subjects int |
| 25 | } |
| 26 | |
| 27 | // Reconcile is the daily tick's work. It lists every subscription on the |
| 28 | // Stripe account and, for each, takes its lock, fetches it again and syncs |
| 29 | // it (ruling R35: a listed snapshot was read outside the lock, and a |
| 30 | // webhook may have written a newer one since), with what the subscription |
| 31 | // itself says of |
| 32 | // its buyer (Checkout's abono_subject metadata, then the customer's |
| 33 | // address, as a subscription event does), which makes up for a webhook |
| 34 | // Stripe gave up on (a subscription that fails to sync is reported, by id, |
| 35 | // and the rest carry on; only the listing itself failing stops the walk); it refreshes every price's interval, amount and |
| 36 | // currency; and it runs OnChange for every distinct subject that holds any |
| 37 | // subscription row or comp, each in its own transaction. That last step is |
| 38 | // how a comp or a paid period that ran out is told to the app, which no |
| 39 | // event announces. |
| 40 | // |
| 41 | // OnChange must therefore be idempotent: Reconcile calls it for subjects |
| 42 | // whose answer has not moved, a deliberate superset of the ones whose has. |
| 43 | // |
| 44 | // The three steps run independently, so a Stripe outage does not stop the |
| 45 | // sweep for comps that need no Stripe. Their errors are joined. Off (no |
| 46 | // key), only the sweep runs. |
| 47 | func (s *Service) Reconcile(ctx context.Context) (Report, error) { |
| 48 | var rep Report |
| 49 | var errs []error |
| 50 | if s.On() { |
| 51 | err := s.stripe.ListSubscriptions(ctx, func(listed stripeapi.Subscription) error { |
| 52 | rep.Subscriptions++ |
| 53 | // One subscription failing (the app's Holder or OnChange, say) |
| 54 | // must not stop the rest being refreshed on every tick after. |
| 55 | if err := s.reconcileOne(ctx, listed.ID); err != nil { |
| 56 | rep.Failed++ |
| 57 | s.noteRefusedKey(err) |
| 58 | errs = append(errs, fmt.Errorf("abono: reconcile: subscription %s: %w", listed.ID, err)) |
| 59 | } |
| 60 | return nil |
| 61 | }) |
| 62 | if err != nil { |
| 63 | s.noteRefusedKey(err) |
| 64 | errs = append(errs, fmt.Errorf("abono: reconcile subscriptions: %w", err)) |
| 65 | } |
| 66 | errs = append(errs, s.refreshPrices(ctx)...) |
| 67 | } |
| 68 | |
| 69 | var subjects []string |
| 70 | if err := s.cfg.DB.WithContext(ctx).Raw(`SELECT subject FROM abono_subscriptions WHERE subject <> '' |
| 71 | UNION SELECT subject FROM abono_comps WHERE subject <> '' ORDER BY subject`).Scan(&subjects).Error; err != nil { |
| 72 | return rep, errors.Join(append(errs, fmt.Errorf("abono: reconcile subjects: %w", err))...) |
| 73 | } |
| 74 | for _, subject := range subjects { |
| 75 | err := s.tx(ctx, func(tx *gorm.DB) error { return s.changed(ctx, tx, subject) }) |
| 76 | if err != nil { |
| 77 | errs = append(errs, fmt.Errorf("abono: reconcile: telling %q: %w", subject, err)) |
| 78 | continue |
| 79 | } |
| 80 | rep.Subjects++ |
| 81 | } |
| 82 | return rep, errors.Join(errs...) |
| 83 | } |
| 84 | |
| 85 | // reconcileOne fetches subscription id again, inside its lock, and syncs |
| 86 | // it. One deleted since the listing is skipped. |
| 87 | func (s *Service) reconcileOne(ctx context.Context, id string) error { |
| 88 | unlock, err := s.subs.lock(ctx, id) |
| 89 | if err != nil { |
| 90 | return err |
| 91 | } |
| 92 | defer unlock() |
| 93 | sub, err := s.stripe.GetSubscription(ctx, id) |
| 94 | switch { |
| 95 | case stripeapi.NotFound(err): |
| 96 | return nil |
| 97 | case err != nil: |
| 98 | return err |
| 99 | } |
| 100 | return s.sync(ctx, sub, subscriptionHint(sub)) |
| 101 | } |
| 102 | |
| 103 | // refreshPrices reads every known price again. A price that cannot be read |
| 104 | // is reported and the rest carry on. |
| 105 | func (s *Service) refreshPrices(ctx context.Context) []error { |
| 106 | var ids []string |
| 107 | if err := s.cfg.DB.WithContext(ctx).Raw(`SELECT stripe_price_id FROM abono_prices ORDER BY stripe_price_id`).Scan(&ids).Error; err != nil { |
| 108 | return []error{fmt.Errorf("abono: reconcile prices: %w", err)} |
| 109 | } |
| 110 | var errs []error |
| 111 | for _, id := range ids { |
| 112 | if err := s.refreshPrice(ctx, id); err != nil { |
| 113 | s.noteRefusedKey(err) |
| 114 | errs = append(errs, err) |
| 115 | } |
| 116 | } |
| 117 | return errs |
| 118 | } |
| 119 | |
amadan