feat: mail service

2026-04-17 18:39:16 +02:00
parent 23ffcb7535
commit 5b7593e6f6
183 changed files with 31215 additions and 248 deletions
@@ -0,0 +1,366 @@
+// Package resenddelivery implements trusted operator resend by clone creation.
+package resenddelivery
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log/slog"
+	"time"
+
+	"galaxy/mail/internal/domain/attempt"
+	"galaxy/mail/internal/domain/common"
+	deliverydomain "galaxy/mail/internal/domain/delivery"
+	"galaxy/mail/internal/logging"
+	"galaxy/mail/internal/service/acceptgenericdelivery"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	oteltrace "go.opentelemetry.io/otel/trace"
+)
+
+var (
+	// ErrNotFound reports that the requested original delivery does not exist.
+	ErrNotFound = errors.New("resend delivery not found")
+
+	// ErrNotAllowed reports that the original delivery is not in a terminal
+	// state and therefore cannot be cloned for resend.
+	ErrNotAllowed = errors.New("resend delivery not allowed")
+
+	// ErrServiceUnavailable reports that clone creation could not load or
+	// persist durable state safely.
+	ErrServiceUnavailable = errors.New("resend delivery service unavailable")
+)
+
+const tracerName = "galaxy/mail/resenddelivery"
+
+// Input stores one trusted resend request by original delivery identifier.
+type Input struct {
+	// DeliveryID stores the original accepted delivery identifier to clone.
+	DeliveryID common.DeliveryID
+}
+
+// Validate reports whether input contains a complete resend target.
+func (input Input) Validate() error {
+	if err := input.DeliveryID.Validate(); err != nil {
+		return fmt.Errorf("delivery id: %w", err)
+	}
+
+	return nil
+}
+
+// Result stores the new clone delivery identifier created by resend.
+type Result struct {
+	// DeliveryID stores the identifier of the newly created clone delivery.
+	DeliveryID common.DeliveryID
+}
+
+// Validate reports whether result contains a usable clone delivery identifier.
+func (result Result) Validate() error {
+	if err := result.DeliveryID.Validate(); err != nil {
+		return fmt.Errorf("delivery id: %w", err)
+	}
+
+	return nil
+}
+
+// CreateResendInput stores the durable write set required for one clone-only
+// resend operation.
+type CreateResendInput struct {
+	// Delivery stores the new cloned delivery record.
+	Delivery deliverydomain.Delivery
+
+	// FirstAttempt stores the initial scheduled attempt of the clone.
+	FirstAttempt attempt.Attempt
+
+	// DeliveryPayload stores the optional cloned raw attachment payload bundle.
+	DeliveryPayload *acceptgenericdelivery.DeliveryPayload
+}
+
+// Validate reports whether input contains a complete resend write set.
+func (input CreateResendInput) Validate() error {
+	if err := input.Delivery.Validate(); err != nil {
+		return fmt.Errorf("delivery: %w", err)
+	}
+	if input.Delivery.Source != deliverydomain.SourceOperatorResend {
+		return fmt.Errorf("delivery source must be %q", deliverydomain.SourceOperatorResend)
+	}
+	if input.Delivery.Status != deliverydomain.StatusQueued {
+		return fmt.Errorf("delivery status must be %q", deliverydomain.StatusQueued)
+	}
+	if input.Delivery.AttemptCount != 1 {
+		return errors.New("delivery attempt count must equal 1")
+	}
+	if input.Delivery.LastAttemptStatus != "" {
+		return errors.New("delivery last attempt status must be empty")
+	}
+	if input.Delivery.ProviderSummary != "" {
+		return errors.New("delivery provider summary must be empty")
+	}
+	if input.Delivery.SentAt != nil || input.Delivery.SuppressedAt != nil || input.Delivery.FailedAt != nil || input.Delivery.DeadLetteredAt != nil {
+		return errors.New("delivery terminal timestamps must be empty")
+	}
+	if err := input.FirstAttempt.Validate(); err != nil {
+		return fmt.Errorf("first attempt: %w", err)
+	}
+	if input.FirstAttempt.DeliveryID != input.Delivery.DeliveryID {
+		return errors.New("first attempt delivery id must match delivery id")
+	}
+	if input.FirstAttempt.AttemptNo != 1 {
+		return errors.New("first attempt number must equal 1")
+	}
+	if input.FirstAttempt.Status != attempt.StatusScheduled {
+		return fmt.Errorf("first attempt status must be %q", attempt.StatusScheduled)
+	}
+	if input.DeliveryPayload != nil {
+		if err := input.DeliveryPayload.Validate(); err != nil {
+			return fmt.Errorf("delivery payload: %w", err)
+		}
+		if input.DeliveryPayload.DeliveryID != input.Delivery.DeliveryID {
+			return errors.New("delivery payload delivery id must match delivery id")
+		}
+	}
+
+	return nil
+}
+
+// Store provides the durable delivery state required by clone-only resend.
+type Store interface {
+	// GetDelivery loads one accepted delivery by its identifier.
+	GetDelivery(context.Context, common.DeliveryID) (deliverydomain.Delivery, bool, error)
+
+	// GetDeliveryPayload loads the raw attachment payload bundle of deliveryID
+	// when one exists.
+	GetDeliveryPayload(context.Context, common.DeliveryID) (acceptgenericdelivery.DeliveryPayload, bool, error)
+
+	// CreateResend atomically creates the cloned delivery, its first attempt,
+	// the optional cloned delivery payload, and the related delivery indexes.
+	CreateResend(context.Context, CreateResendInput) error
+}
+
+// DeliveryIDGenerator describes the source of new internal delivery
+// identifiers.
+type DeliveryIDGenerator interface {
+	// NewDeliveryID returns one new internal delivery identifier.
+	NewDeliveryID() (common.DeliveryID, error)
+}
+
+// Clock provides the current wall-clock time.
+type Clock interface {
+	// Now returns the current time.
+	Now() time.Time
+}
+
+// Telemetry records low-cardinality resend metrics.
+type Telemetry interface {
+	// RecordDeliveryStatusTransition records one durable delivery status
+	// transition.
+	RecordDeliveryStatusTransition(context.Context, string, string)
+}
+
+// Config stores the dependencies used by Service.
+type Config struct {
+	// Store owns durable resend state.
+	Store Store
+
+	// DeliveryIDGenerator builds internal clone identifiers.
+	DeliveryIDGenerator DeliveryIDGenerator
+
+	// Clock provides wall-clock timestamps.
+	Clock Clock
+
+	// Telemetry records low-cardinality resend metrics.
+	Telemetry Telemetry
+
+	// TracerProvider constructs the application span recorder used by resend.
+	TracerProvider oteltrace.TracerProvider
+
+	// Logger writes structured resend logs.
+	Logger *slog.Logger
+}
+
+// Service executes clone-only trusted resend requests.
+type Service struct {
+	store               Store
+	deliveryIDGenerator DeliveryIDGenerator
+	clock               Clock
+	telemetry           Telemetry
+	tracerProvider      oteltrace.TracerProvider
+	logger              *slog.Logger
+}
+
+// New constructs Service from cfg.
+func New(cfg Config) (*Service, error) {
+	switch {
+	case cfg.Store == nil:
+		return nil, errors.New("new resend delivery service: nil store")
+	case cfg.DeliveryIDGenerator == nil:
+		return nil, errors.New("new resend delivery service: nil delivery id generator")
+	case cfg.Clock == nil:
+		return nil, errors.New("new resend delivery service: nil clock")
+	default:
+		tracerProvider := cfg.TracerProvider
+		if tracerProvider == nil {
+			tracerProvider = otel.GetTracerProvider()
+		}
+		logger := cfg.Logger
+		if logger == nil {
+			logger = slog.Default()
+		}
+
+		return &Service{
+			store:               cfg.Store,
+			deliveryIDGenerator: cfg.DeliveryIDGenerator,
+			clock:               cfg.Clock,
+			telemetry:           cfg.Telemetry,
+			tracerProvider:      tracerProvider,
+			logger:              logger.With("component", "resend_delivery"),
+		}, nil
+	}
+}
+
+// Execute clones one terminal delivery into a new queued delivery with a
+// fresh first attempt.
+func (service *Service) Execute(ctx context.Context, input Input) (Result, error) {
+	if ctx == nil {
+		return Result{}, errors.New("execute resend delivery: nil context")
+	}
+	if service == nil {
+		return Result{}, errors.New("execute resend delivery: nil service")
+	}
+	if err := input.Validate(); err != nil {
+		return Result{}, fmt.Errorf("execute resend delivery: %w", err)
+	}
+
+	ctx, span := service.tracerProvider.Tracer(tracerName).Start(
+		ctx,
+		"mail.resend_delivery",
+		oteltrace.WithAttributes(attribute.String("mail.parent_delivery_id", input.DeliveryID.String())),
+	)
+	defer span.End()
+
+	original, found, err := service.store.GetDelivery(ctx, input.DeliveryID)
+	switch {
+	case err != nil:
+		return Result{}, fmt.Errorf("%w: load original delivery: %v", ErrServiceUnavailable, err)
+	case !found:
+		return Result{}, ErrNotFound
+	case !original.Status.AllowsResend():
+		return Result{}, ErrNotAllowed
+	}
+
+	now := service.clock.Now().UTC().Truncate(time.Millisecond)
+	cloneID, err := service.deliveryIDGenerator.NewDeliveryID()
+	if err != nil {
+		return Result{}, fmt.Errorf("%w: generate delivery id: %v", ErrServiceUnavailable, err)
+	}
+
+	clone := buildClonedDelivery(original, cloneID, now)
+	firstAttempt := attempt.Attempt{
+		DeliveryID:   cloneID,
+		AttemptNo:    1,
+		ScheduledFor: now,
+		Status:       attempt.StatusScheduled,
+	}
+
+	var clonedPayload *acceptgenericdelivery.DeliveryPayload
+	if len(original.Attachments) > 0 {
+		payload, found, err := service.store.GetDeliveryPayload(ctx, original.DeliveryID)
+		switch {
+		case err != nil:
+			return Result{}, fmt.Errorf("%w: load original delivery payload: %v", ErrServiceUnavailable, err)
+		case !found:
+			return Result{}, fmt.Errorf("%w: missing original delivery payload for %q", ErrServiceUnavailable, original.DeliveryID)
+		default:
+			cloned := cloneDeliveryPayload(payload, cloneID)
+			clonedPayload = &cloned
+		}
+	}
+
+	createInput := CreateResendInput{
+		Delivery:        clone,
+		FirstAttempt:    firstAttempt,
+		DeliveryPayload: clonedPayload,
+	}
+	if err := createInput.Validate(); err != nil {
+		return Result{}, fmt.Errorf("%w: build resend input: %v", ErrServiceUnavailable, err)
+	}
+	if err := service.store.CreateResend(ctx, createInput); err != nil {
+		return Result{}, fmt.Errorf("%w: create resend clone: %v", ErrServiceUnavailable, err)
+	}
+	service.recordStatusTransition(ctx, createInput.Delivery)
+
+	result := Result{DeliveryID: cloneID}
+	if err := result.Validate(); err != nil {
+		return Result{}, fmt.Errorf("%w: invalid result: %v", ErrServiceUnavailable, err)
+	}
+	span.SetAttributes(
+		attribute.String("mail.delivery_id", cloneID.String()),
+		attribute.String("mail.source", string(createInput.Delivery.Source)),
+	)
+	logArgs := logging.DeliveryAttrs(createInput.Delivery)
+	logArgs = append(logArgs,
+		"parent_delivery_id", original.DeliveryID.String(),
+		"status", string(createInput.Delivery.Status),
+	)
+	logArgs = append(logArgs, logging.TraceAttrsFromContext(ctx)...)
+	service.logger.Info("resend clone created", logArgs...)
+
+	return result, nil
+}
+
+func (service *Service) recordStatusTransition(ctx context.Context, record deliverydomain.Delivery) {
+	if service == nil || service.telemetry == nil {
+		return
+	}
+
+	service.telemetry.RecordDeliveryStatusTransition(ctx, string(record.Status), string(record.Source))
+}
+
+func buildClonedDelivery(original deliverydomain.Delivery, cloneID common.DeliveryID, now time.Time) deliverydomain.Delivery {
+	return deliverydomain.Delivery{
+		DeliveryID:             cloneID,
+		ResendParentDeliveryID: original.DeliveryID,
+		Source:                 deliverydomain.SourceOperatorResend,
+		PayloadMode:            original.PayloadMode,
+		TemplateID:             original.TemplateID,
+		Envelope: deliverydomain.Envelope{
+			To:      append([]common.Email(nil), original.Envelope.To...),
+			Cc:      append([]common.Email(nil), original.Envelope.Cc...),
+			Bcc:     append([]common.Email(nil), original.Envelope.Bcc...),
+			ReplyTo: append([]common.Email(nil), original.Envelope.ReplyTo...),
+		},
+		Content:            original.Content,
+		Attachments:        append([]common.AttachmentMetadata(nil), original.Attachments...),
+		Locale:             original.Locale,
+		LocaleFallbackUsed: original.LocaleFallbackUsed,
+		TemplateVariables:  cloneJSONObject(original.TemplateVariables),
+		IdempotencyKey:     common.IdempotencyKey("operator:resend:" + original.DeliveryID.String()),
+		Status:             deliverydomain.StatusQueued,
+		AttemptCount:       1,
+		CreatedAt:          now,
+		UpdatedAt:          now,
+	}
+}
+
+func cloneDeliveryPayload(payload acceptgenericdelivery.DeliveryPayload, cloneID common.DeliveryID) acceptgenericdelivery.DeliveryPayload {
+	cloned := acceptgenericdelivery.DeliveryPayload{
+		DeliveryID:  cloneID,
+		Attachments: make([]acceptgenericdelivery.AttachmentPayload, len(payload.Attachments)),
+	}
+	copy(cloned.Attachments, payload.Attachments)
+	return cloned
+}
+
+func cloneJSONObject(value map[string]any) map[string]any {
+	if value == nil {
+		return nil
+	}
+
+	cloned := make(map[string]any, len(value))
+	for key, entry := range value {
+		cloned[key] = entry
+	}
+
+	return cloned
+}