Add end-to-end tests for TLS RPT report ingestion and WebSocket event handling

- Implemented tests for ingesting TLS RPT reports from emails and ensuring they are stored correctly in the database.
- Added tests to verify that the same report can be ingested multiple times without duplication.
- Created tests for backfilling reports that were previously delivered to the inbox.
- Developed WebSocket event handling tests to ensure events are correctly routed to subscribers based on mailbox ownership.
- Included tests for the mail API to validate session handling, mailbox isolation, and error mapping.
- Ensured that the API rejects unauthorized requests and handles malformed JSON gracefully.

services/protocols/internal/application/usecase/backfill_reports.go

@@ -0,0 +1,89 @@
+package usecase
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"lambdamail/protocols/internal/application/port"
+)
+
+// BackfillReportsUseCase parses reports that were delivered before automatic
+// ingestion existed.
+//
+// Every report received until now was filed in the admin's inbox as an
+// attachment and never read, so the tables the admin console shows start
+// empty however long the server has been running. The messages are still
+// stored, so the backlog can be parsed after the fact and filed out of the
+// inbox at the same time.
+type BackfillReportsUseCase struct {
+	store    port.DeliveredReportStore
+	blobs    port.BlobReader
+	ingestor *IngestDeliveredReportsUseCase
+}
+
+func NewBackfillReportsUseCase(
+	store port.DeliveredReportStore,
+	blobs port.BlobReader,
+	ingestor *IngestDeliveredReportsUseCase,
+) *BackfillReportsUseCase {
+	return &BackfillReportsUseCase{store: store, blobs: blobs, ingestor: ingestor}
+}
+
+// BackfillSummary is what one run did, for the operator running it by hand.
+type BackfillSummary struct {
+	// Scanned is how many stored report messages were examined.
+	Scanned int
+	// Ingested is how many produced a report row.
+	Ingested int
+	// Failed is how many could not be read or parsed. They are left filed in
+	// Reports with their bytes intact, so a later run can retry them.
+	Failed int
+}
+
+// Run parses the backlog. limit caps how many messages are examined; 0 means
+// whatever the store considers a full pass.
+//
+// Only a failure to read the backlog itself stops the run. An individual
+// message that cannot be read or parsed is counted and skipped: one corrupt
+// attachment from years ago must not block every report behind it.
+func (uc *BackfillReportsUseCase) Run(ctx context.Context, limit int) (BackfillSummary, error) {
+	summary := BackfillSummary{}
+
+	pending, err := uc.store.ListUningestedReports(ctx, limit)
+	if err != nil {
+		return summary, fmt.Errorf("list the report backlog: %w", err)
+	}
+
+	for _, msg := range pending {
+		summary.Scanned++
+
+		raw, err := uc.blobs.ReadByID(ctx, msg.BlobID)
+		if err != nil {
+			summary.Failed++
+			log.Printf("backfill: could not read the message for %s: %v", msg.RecipientAddress, err)
+			continue
+		}
+
+		outcome, err := uc.ingestor.Ingest(ctx, []string{msg.RecipientAddress}, raw)
+		switch {
+		case err != nil:
+			summary.Failed++
+			log.Printf("backfill: could not ingest the message for %s: %v", msg.RecipientAddress, err)
+		case outcome.Stored:
+			summary.Ingested++
+		default:
+			// Recognised as a report but nothing parseable inside it.
+			summary.Failed++
+		}
+
+		// Filed either way. The inbox is being cleared, and a report this
+		// server cannot parse today is still a report - its bytes stay on
+		// disk, so a later run can try again once the parser is fixed.
+		if err := uc.store.MoveToReportsFolder(ctx, msg.MessageID); err != nil {
+			log.Printf("backfill: could not file %s into %s: %v", msg.MessageID, ReportsFolderName, err)
+		}
+	}
+
+	return summary, nil
+}

services/protocols/internal/application/usecase/backfill_reports_test.go

@@ -0,0 +1,172 @@
+package usecase
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/google/uuid"
+
+	"lambdamail/protocols/internal/application/port"
+)
+
+// Reports that arrived before ingestion existed are still sitting in the
+// admin's inbox. They are ordinary stored messages, so they can be read back
+// out and parsed after the fact.
+
+type stubDeliveredReportStore struct {
+	pending []port.StoredReportMessage
+	filed   []uuid.UUID
+	blobs   map[uuid.UUID][]byte
+	listErr error
+	fileErr error
+	blobErr error
+}
+
+func (s *stubDeliveredReportStore) ListUningestedReports(
+	_ context.Context, limit int,
+) ([]port.StoredReportMessage, error) {
+	if s.listErr != nil {
+		return nil, s.listErr
+	}
+	if limit > 0 && len(s.pending) > limit {
+		return s.pending[:limit], nil
+	}
+	return s.pending, nil
+}
+
+func (s *stubDeliveredReportStore) MoveToReportsFolder(_ context.Context, messageID uuid.UUID) error {
+	if s.fileErr != nil {
+		return s.fileErr
+	}
+	s.filed = append(s.filed, messageID)
+	return nil
+}
+
+func (s *stubDeliveredReportStore) ReadByID(_ context.Context, blobID uuid.UUID) ([]byte, error) {
+	if s.blobErr != nil {
+		return nil, s.blobErr
+	}
+	body, ok := s.blobs[blobID]
+	if !ok {
+		return nil, errors.New("blob not found")
+	}
+	return body, nil
+}
+
+func newBackfill(store *stubDeliveredReportStore, repo *recordingReportRepo) *BackfillReportsUseCase {
+	return NewBackfillReportsUseCase(
+		store, store, NewIngestDeliveredReportsUseCase(NewIngestReportsUseCase(repo)))
+}
+
+func TestBackfillIngestsAReportAlreadyInTheMailbox(t *testing.T) {
+	blobID := uuid.New()
+	messageID := uuid.New()
+	payload := messageWithAttachment(googleTlsRptFilename, "application/gzip", gzipped(t, tlsRptJSON))
+
+	store := &stubDeliveredReportStore{
+		pending: []port.StoredReportMessage{
+			{MessageID: messageID, BlobID: blobID, RecipientAddress: "tlsrpt@example.test"},
+		},
+		blobs: map[uuid.UUID][]byte{blobID: payload},
+	}
+	repo := &recordingReportRepo{}
+
+	summary, err := newBackfill(store, repo).Run(context.Background(), 0)
+	if err != nil {
+		t.Fatalf("run: %v", err)
+	}
+
+	if len(repo.tlsRpt) != 1 {
+		t.Fatalf("the stored report was not ingested: %d", len(repo.tlsRpt))
+	}
+	if repo.tlsRpt[0].Domain != "example.test" {
+		t.Errorf("ingested domain is %q", repo.tlsRpt[0].Domain)
+	}
+	if summary.Ingested != 1 {
+		t.Errorf("summary reports %d ingested, want 1", summary.Ingested)
+	}
+	// Filed out of the inbox, which is the point of running this at all.
+	if len(store.filed) != 1 || store.filed[0] != messageID {
+		t.Errorf("the message was not moved to Reports: %v", store.filed)
+	}
+}
+
+// Running it twice must be safe: the second pass has nothing left to do, and
+// storage is idempotent anyway.
+func TestBackfillOverAnEmptyBacklogDoesNothing(t *testing.T) {
+	store := &stubDeliveredReportStore{}
+	repo := &recordingReportRepo{}
+
+	summary, err := newBackfill(store, repo).Run(context.Background(), 0)
+	if err != nil {
+		t.Fatalf("run: %v", err)
+	}
+	if summary.Ingested != 0 || summary.Failed != 0 {
+		t.Errorf("an empty backlog produced %+v", summary)
+	}
+}
+
+// One unreadable report must not stop the rest of the backlog: a single
+// corrupted attachment from years ago would otherwise block every report
+// behind it forever.
+func TestBackfillContinuesPastAnUnreadableReport(t *testing.T) {
+	goodBlob, badBlob := uuid.New(), uuid.New()
+	goodMsg, badMsg := uuid.New(), uuid.New()
+
+	store := &stubDeliveredReportStore{
+		pending: []port.StoredReportMessage{
+			{MessageID: badMsg, BlobID: badBlob, RecipientAddress: "tlsrpt@example.test"},
+			{MessageID: goodMsg, BlobID: goodBlob, RecipientAddress: "tlsrpt@example.test"},
+		},
+		blobs: map[uuid.UUID][]byte{
+			badBlob:  messageWithAttachment("broken.json.gz", "application/gzip", []byte("rubbish")),
+			goodBlob: messageWithAttachment(googleTlsRptFilename, "application/gzip", gzipped(t, tlsRptJSON)),
+		},
+	}
+	repo := &recordingReportRepo{}
+
+	summary, err := newBackfill(store, repo).Run(context.Background(), 0)
+	if err != nil {
+		t.Fatalf("run: %v", err)
+	}
+	if summary.Ingested != 1 {
+		t.Errorf("the readable report was not ingested: %+v", summary)
+	}
+	if summary.Failed != 1 {
+		t.Errorf("the unreadable one was not reported: %+v", summary)
+	}
+	// Both are filed either way - the inbox is being cleared, and a report
+	// this server cannot parse is still a report.
+	if len(store.filed) != 2 {
+		t.Errorf("filed %d messages, want both", len(store.filed))
+	}
+}
+
+// A blob that cannot be read at all is counted and skipped, never fatal.
+func TestBackfillSurvivesAMissingBlob(t *testing.T) {
+	store := &stubDeliveredReportStore{
+		pending: []port.StoredReportMessage{
+			{MessageID: uuid.New(), BlobID: uuid.New(), RecipientAddress: "dmarc@example.test"},
+		},
+		blobs: map[uuid.UUID][]byte{},
+	}
+	repo := &recordingReportRepo{}
+
+	summary, err := newBackfill(store, repo).Run(context.Background(), 0)
+	if err != nil {
+		t.Fatalf("a missing blob must not fail the run: %v", err)
+	}
+	if summary.Failed != 1 {
+		t.Errorf("the missing blob was not counted: %+v", summary)
+	}
+}
+
+// A failure listing the backlog is the one thing worth stopping for: it means
+// the database is unreachable, and every message would be counted as failed.
+func TestBackfillStopsIfItCannotReadTheBacklog(t *testing.T) {
+	store := &stubDeliveredReportStore{listErr: errors.New("database is down")}
+	if _, err := newBackfill(store, &recordingReportRepo{}).Run(context.Background(), 0); err == nil {
+		t.Error("a backlog that cannot be listed should be reported as an error")
+	}
+}

services/protocols/internal/application/usecase/ingest_delivered_reports.go

@@ -0,0 +1,188 @@
+package usecase
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"log"
+	"strings"
+
+	"github.com/emersion/go-message"
+)
+
+// ReportKind says what a delivered message is, decided by the address it was
+// sent to.
+type ReportKind string
+
+const (
+	// ReportKindNone is ordinary mail, which this use case leaves alone.
+	ReportKindNone   ReportKind = ""
+	ReportKindDmarc  ReportKind = "dmarc"
+	ReportKindTlsRpt ReportKind = "tlsrpt"
+)
+
+// reportLocalParts maps the mailbox a report is addressed to onto what it
+// contains.
+//
+// The address is the only trustworthy signal. The subject and the attachment
+// filename are both chosen by the sender, so keying on either would let anyone
+// who can send this server a message write rows into the report tables. These
+// local parts exist because EnsureSystemAliases creates them for every domain.
+var reportLocalParts = map[string]ReportKind{
+	"dmarc":  ReportKindDmarc,
+	"tlsrpt": ReportKindTlsRpt,
+}
+
+// ReportsFolderName is where an ingested report is filed.
+//
+// Not the inbox: these are machine-to-machine documents that arrive daily from
+// every large receiver, and nobody reads the attachment by hand. Not discarded
+// either - keeping the original bytes is what makes a parser fix re-appliable
+// to reports already received.
+const ReportsFolderName = "Reports"
+
+// IngestDeliveredReportsUseCase reads DMARC and TLS-RPT reports out of the
+// mail that carries them.
+//
+// The parsers, the tables and the HTTP ingest endpoints all existed already,
+// but nothing connected inbound mail to them: reports were filed in the
+// admin's inbox as attachments nobody could read, and the report tables stayed
+// empty however many arrived.
+type IngestDeliveredReportsUseCase struct {
+	reports *IngestReportsUseCase
+}
+
+func NewIngestDeliveredReportsUseCase(reports *IngestReportsUseCase) *IngestDeliveredReportsUseCase {
+	return &IngestDeliveredReportsUseCase{reports: reports}
+}
+
+// Ingest parses any report the message carries and reports what kind of
+// message it was, so the caller can file it somewhere other than the inbox.
+//
+// It never returns an error for a bad report. A malformed payload is the
+// reporter's mistake and a storage failure is this server's, and neither is a
+// reason to answer the SMTP transaction with a failure: the reporter would
+// retry the same message on a schedule, forever, and no retry would ever help.
+// Failures are logged and the message is still delivered, which also leaves
+// the original bytes on disk to re-ingest once the cause is fixed.
+func (uc *IngestDeliveredReportsUseCase) Ingest(
+	ctx context.Context, recipients []string, payload []byte,
+) (ReportOutcome, error) {
+	kind := ReportKindNone
+	for _, address := range recipients {
+		if found := reportKindForAddress(address); found != ReportKindNone {
+			kind = found
+			break
+		}
+	}
+	if kind == ReportKindNone || uc.reports == nil {
+		return ReportOutcome{}, nil
+	}
+
+	// Every part is tried in turn, so the covering note a reporter puts in
+	// front of the attachment is simply one that does not parse. Only the
+	// last failure is kept, and only reported if no part worked at all:
+	// logging each one would file an error for the human-readable part of
+	// every report that ingests perfectly well.
+	var lastErr error
+	for _, candidate := range reportPayloads(payload) {
+		var err error
+		switch kind {
+		case ReportKindDmarc:
+			_, err = uc.reports.IngestDmarc(ctx, candidate)
+		case ReportKindTlsRpt:
+			_, err = uc.reports.IngestTlsRpt(ctx, candidate)
+		}
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		// One report per message, so there is nothing to gain from reading
+		// the remaining parts once one has been stored.
+		return ReportOutcome{Kind: kind, Stored: true}, nil
+	}
+
+	if lastErr != nil {
+		// Logged rather than returned: see the note above on why a bad report
+		// must not fail the delivery.
+		log.Printf("reports: no readable %s report in a message to %v: %v", kind, recipients, lastErr)
+	}
+	// Recognised by its address but nothing could be parsed out of it. Still a
+	// report, so the caller files it with the others rather than leaving it in
+	// the inbox.
+	return ReportOutcome{Kind: kind}, nil
+}
+
+// ReportOutcome says what a message turned out to be and whether anything was
+// actually stored from it.
+//
+// The two are separate because they drive different decisions: Kind decides
+// where the message is filed, and Stored is how a caller tells a report it
+// parsed from one it merely recognised - which Ingest deliberately does not
+// report as an error.
+type ReportOutcome struct {
+	Kind   ReportKind
+	Stored bool
+}
+
+// reportKindForAddress classifies one recipient address by its local part.
+func reportKindForAddress(address string) ReportKind {
+	local, _, found := strings.Cut(address, "@")
+	if !found {
+		return ReportKindNone
+	}
+	return reportLocalParts[strings.ToLower(strings.TrimSpace(local))]
+}
+
+// reportPayloads returns every part of the message that could be a report,
+// decoded.
+//
+// Every attachment is offered rather than the one whose name looks right:
+// filenames vary between reporters and the parsers already reject anything
+// that is not a report, so matching on the name would only add a way to miss
+// one. The whole body is offered last, for the reporters that send the
+// document as the message itself rather than as an attachment.
+func reportPayloads(payload []byte) [][]byte {
+	entity, err := message.Read(bytes.NewReader(payload))
+	if err != nil {
+		return [][]byte{payload}
+	}
+
+	candidates := collectReportParts(entity, 0)
+	return append(candidates, payload)
+}
+
+// maxReportParts bounds the walk: a report has one attachment, and a message
+// with hundreds of nested parts is not one this server needs to read.
+const maxReportParts = 16
+
+// maxReportPartBytes bounds each part. Aggregate reports are XML or JSON in
+// the tens of kilobytes even before compression.
+const maxReportPartBytes = 32 << 20
+
+func collectReportParts(entity *message.Entity, depth int) [][]byte {
+	// Bounded so a deliberately deep MIME tree cannot drive this into a
+	// pathological walk.
+	if depth > 8 {
+		return nil
+	}
+	if multipart := entity.MultipartReader(); multipart != nil {
+		out := [][]byte{}
+		for len(out) < maxReportParts {
+			part, err := multipart.NextPart()
+			if err != nil {
+				break
+			}
+			out = append(out, collectReportParts(part, depth+1)...)
+		}
+		return out
+	}
+
+	// go-message decodes the transfer encoding as the body is read, so what
+	// comes back here is the attachment's real bytes rather than its base64.
+	body, err := io.ReadAll(io.LimitReader(entity.Body, maxReportPartBytes))
+	if err != nil || len(body) == 0 {
+		return nil
+	}
+	return [][]byte{body}
+}

services/protocols/internal/application/usecase/ingest_delivered_reports_test.go

@@ -0,0 +1,318 @@
+package usecase
+
+import (
+	"bytes"
+	"compress/gzip"
+	"context"
+	"encoding/base64"
+	"errors"
+	"testing"
+
+	"github.com/google/uuid"
+
+	"lambdamail/protocols/internal/application/port"
+	"lambdamail/protocols/internal/domain/entity"
+)
+
+// Reports arrive as ordinary mail to the addresses the system aliases
+// guarantee exist. Nothing read them: they were filed in the admin's inbox as
+// attachments and the parsed tables stayed empty.
+
+type recordingReportRepo struct {
+	dmarc  []*entity.DmarcReport
+	tlsRpt []*entity.TlsRptReport
+	err    error
+}
+
+func (r *recordingReportRepo) SaveDmarcReport(_ context.Context, report *entity.DmarcReport) error {
+	if r.err != nil {
+		return r.err
+	}
+	r.dmarc = append(r.dmarc, report)
+	return nil
+}
+
+func (r *recordingReportRepo) SaveTlsRptReport(_ context.Context, report *entity.TlsRptReport) error {
+	if r.err != nil {
+		return r.err
+	}
+	r.tlsRpt = append(r.tlsRpt, report)
+	return nil
+}
+
+// gzipped compresses a payload the way a reporter does before attaching it.
+func gzipped(t *testing.T, payload string) []byte {
+	t.Helper()
+	var buf bytes.Buffer
+	gz := gzip.NewWriter(&buf)
+	if _, err := gz.Write([]byte(payload)); err != nil {
+		t.Fatal(err)
+	}
+	if err := gz.Close(); err != nil {
+		t.Fatal(err)
+	}
+	return buf.Bytes()
+}
+
+// messageWithAttachment builds the shape a reporter actually sends: a short
+// human-readable part plus the report as a base64 attachment.
+func messageWithAttachment(filename, contentType string, content []byte) []byte {
+	encoded := base64.StdEncoding.EncodeToString(content)
+	var b bytes.Buffer
+	b.WriteString("From: noreply-dmarc-support@google.com\r\n")
+	b.WriteString("Subject: Report Domain: example.test\r\n")
+	b.WriteString("MIME-Version: 1.0\r\n")
+	b.WriteString("Content-Type: multipart/mixed; boundary=\"sep\"\r\n\r\n")
+	b.WriteString("--sep\r\n")
+	b.WriteString("Content-Type: text/plain; charset=utf-8\r\n\r\n")
+	b.WriteString("This is an aggregate report.\r\n")
+	b.WriteString("--sep\r\n")
+	b.WriteString("Content-Type: " + contentType + "; name=\"" + filename + "\"\r\n")
+	b.WriteString("Content-Disposition: attachment; filename=\"" + filename + "\"\r\n")
+	b.WriteString("Content-Transfer-Encoding: base64\r\n\r\n")
+	for len(encoded) > 76 {
+		b.WriteString(encoded[:76] + "\r\n")
+		encoded = encoded[76:]
+	}
+	b.WriteString(encoded + "\r\n")
+	b.WriteString("--sep--\r\n")
+	return b.Bytes()
+}
+
+const tlsRptJSON = `{"organization-name":"Google Inc.",` +
+	`"date-range":{"start-datetime":"2026-08-19T00:00:00Z","end-datetime":"2026-08-19T23:59:59Z"},` +
+	`"report-id":"2026-08-19T00:00:00Z_example.test",` +
+	`"policies":[{"policy":{"policy-type":"no-policy-found","policy-domain":"example.test"},` +
+	`"summary":{"total-successful-session-count":2,"total-failure-session-count":0}}]}`
+
+// The exact filename Google uses, which is what arrives in the inbox today.
+const googleTlsRptFilename = "google.com!example.test!1787097600!1787183999!001.json.gz"
+
+func newReportIngestor(repo *recordingReportRepo) *IngestDeliveredReportsUseCase {
+	return NewIngestDeliveredReportsUseCase(NewIngestReportsUseCase(repo))
+}
+
+func TestTlsRptReportAddressedToTlsRptIsIngested(t *testing.T) {
+	repo := &recordingReportRepo{}
+	uc := newReportIngestor(repo)
+
+	payload := messageWithAttachment(googleTlsRptFilename, "application/gzip", gzipped(t, tlsRptJSON))
+
+	outcome, err := uc.Ingest(context.Background(), []string{"tlsrpt@example.test"}, payload)
+	if err != nil {
+		t.Fatalf("ingest: %v", err)
+	}
+	if outcome.Kind != ReportKindTlsRpt {
+		t.Errorf("kind is %q, want tlsrpt", outcome.Kind)
+	}
+	if len(repo.tlsRpt) != 1 {
+		t.Fatalf("want 1 stored report, got %d", len(repo.tlsRpt))
+	}
+	if repo.tlsRpt[0].Domain != "example.test" {
+		t.Errorf("stored domain is %q", repo.tlsRpt[0].Domain)
+	}
+}
+
+func TestDmarcReportAddressedToDmarcIsIngested(t *testing.T) {
+	repo := &recordingReportRepo{}
+	uc := newReportIngestor(repo)
+
+	payload := messageWithAttachment(
+		"google.com!example.test!1787097600!1787183999.xml.gz",
+		"application/gzip", gzipped(t, dmarcAggregateXMLFixture))
+
+	outcome, err := uc.Ingest(context.Background(), []string{"dmarc@example.test"}, payload)
+	if err != nil {
+		t.Fatalf("ingest: %v", err)
+	}
+	if outcome.Kind != ReportKindDmarc {
+		t.Errorf("kind is %q, want dmarc", outcome.Kind)
+	}
+	if len(repo.dmarc) != 1 {
+		t.Fatalf("want 1 stored report, got %d", len(repo.dmarc))
+	}
+}
+
+// The address decides, not the subject or the filename - both of which the
+// sender chooses freely. Ordinary mail must pass through untouched.
+func TestOrdinaryMailIsNotTreatedAsAReport(t *testing.T) {
+	repo := &recordingReportRepo{}
+	uc := newReportIngestor(repo)
+
+	payload := messageWithAttachment(googleTlsRptFilename, "application/gzip", gzipped(t, tlsRptJSON))
+
+	outcome, err := uc.Ingest(context.Background(), []string{"lucas@example.test"}, payload)
+	if err != nil {
+		t.Fatalf("ingest: %v", err)
+	}
+	if outcome.Kind != ReportKindNone {
+		t.Errorf("ordinary mail was classified as %q", outcome.Kind)
+	}
+	if len(repo.tlsRpt) != 0 || len(repo.dmarc) != 0 {
+		t.Error("a report was stored from mail addressed to a person")
+	}
+}
+
+// A report this server cannot parse is still a report: it must be recognised,
+// so it files with the others, and it must never fail the delivery. Returning
+// an error here would have the reporter retry the same broken payload forever.
+func TestUnparseableReportIsRecognisedButNeverFailsDelivery(t *testing.T) {
+	repo := &recordingReportRepo{}
+	uc := newReportIngestor(repo)
+
+	payload := messageWithAttachment("broken.json.gz", "application/gzip", []byte("not a report at all"))
+
+	outcome, err := uc.Ingest(context.Background(), []string{"tlsrpt@example.test"}, payload)
+	if err != nil {
+		t.Fatalf("a malformed report must not fail the delivery: %v", err)
+	}
+	if outcome.Kind != ReportKindTlsRpt {
+		t.Errorf("kind is %q; the address still says what this message is", outcome.Kind)
+	}
+	if len(repo.tlsRpt) != 0 {
+		t.Error("an unparseable payload was stored")
+	}
+}
+
+// A storage failure is this server's problem, not the reporter's, and must not
+// turn into an SMTP error either.
+func TestStorageFailureDoesNotFailDelivery(t *testing.T) {
+	repo := &recordingReportRepo{err: errors.New("database is down")}
+	uc := newReportIngestor(repo)
+
+	payload := messageWithAttachment(googleTlsRptFilename, "application/gzip", gzipped(t, tlsRptJSON))
+
+	if _, err := uc.Ingest(context.Background(), []string{"tlsrpt@example.test"}, payload); err != nil {
+		t.Errorf("a storage failure must not fail the delivery: %v", err)
+	}
+}
+
+// Reporters vary the local part: dmarc-reports@, tlsrpt@, and the aliases this
+// server creates. Matching is on the local part, case-insensitively.
+func TestReportAddressMatchingIsCaseInsensitive(t *testing.T) {
+	for _, address := range []string{"TLSRPT@example.test", "TlsRpt@Example.Test"} {
+		if got := reportKindForAddress(address); got != ReportKindTlsRpt {
+			t.Errorf("%s classified as %q, want tlsrpt", address, got)
+		}
+	}
+	if got := reportKindForAddress("DMARC@example.test"); got != ReportKindDmarc {
+		t.Errorf("DMARC@ classified as %q", got)
+	}
+}
+
+// A report with no attachment at all - some reporters inline small ones - must
+// still not fail, and must still be recognised by its address.
+func TestReportWithNoAttachmentDoesNotFail(t *testing.T) {
+	repo := &recordingReportRepo{}
+	uc := newReportIngestor(repo)
+
+	payload := []byte("From: a@b.test\r\nSubject: hi\r\n\r\nno attachment here\r\n")
+	outcome, err := uc.Ingest(context.Background(), []string{"tlsrpt@example.test"}, payload)
+	if err != nil {
+		t.Fatalf("ingest: %v", err)
+	}
+	if outcome.Kind != ReportKindTlsRpt {
+		t.Errorf("kind is %q", outcome.Kind)
+	}
+}
+
+// A DMARC aggregate report, trimmed to the fields the parser reads.
+const dmarcAggregateXMLFixture = `<?xml version="1.0" encoding="UTF-8" ?>
+<feedback>
+  <report_metadata>
+    <org_name>google.com</org_name>
+    <report_id>987654321</report_id>
+    <date_range><begin>1787097600</begin><end>1787183999</end></date_range>
+  </report_metadata>
+  <policy_published><domain>example.test</domain><p>quarantine</p></policy_published>
+  <record>
+    <row>
+      <source_ip>203.0.113.10</source_ip>
+      <count>1</count>
+      <policy_evaluated><disposition>none</disposition><dkim>pass</dkim><spf>pass</spf></policy_evaluated>
+    </row>
+    <identifiers><header_from>example.test</header_from></identifiers>
+  </record>
+</feedback>`
+
+// --- the delivery path ---------------------------------------------------
+
+// A report must be ingested and filed out of the way in one delivery, without
+// the address ever having to be a real mailbox the user reads.
+func TestDeliveredReportIsIngestedAndFiledInReports(t *testing.T) {
+	repo := &recordingReportRepo{}
+	messages := &recordingMessageRepository{}
+	uc := NewProcessInboundEmailUseCase(nil, &capturingBlobStorage{}, messages)
+	uc.SetReportIngestor(newReportIngestor(repo))
+
+	payload := messageWithAttachment(googleTlsRptFilename, "application/gzip", gzipped(t, tlsRptJSON))
+	if err := uc.Handle(context.Background(), ProcessInboundEmailInput{
+		Sender:             "smtp-tls-reporting@google.com",
+		Recipients:         []port.MailboxRecord{{ID: uuid.New()}},
+		RecipientAddresses: []string{"tlsrpt@example.test"},
+		Body:               bytes.NewReader(payload),
+	}); err != nil {
+		t.Fatalf("Handle: %v", err)
+	}
+
+	if len(repo.tlsRpt) != 1 {
+		t.Fatalf("the report was not ingested: %d stored", len(repo.tlsRpt))
+	}
+	if len(messages.persisted) != 1 {
+		t.Fatalf("want the message filed once, got %d", len(messages.persisted))
+	}
+	filed := messages.persisted[0]
+	if filed.TargetFolderName != ReportsFolderName {
+		t.Errorf("the report was filed in %q, want %q", filed.TargetFolderName, ReportsFolderName)
+	}
+	// It is machine-read mail; raising an unread badge for it would recreate
+	// the inbox noise this exists to remove.
+	if !filed.AlreadySeen {
+		t.Error("the filed report was counted as unread mail")
+	}
+}
+
+// Ordinary mail must reach the inbox exactly as before.
+func TestOrdinaryMailStillReachesTheInbox(t *testing.T) {
+	repo := &recordingReportRepo{}
+	messages := &recordingMessageRepository{}
+	uc := NewProcessInboundEmailUseCase(nil, &capturingBlobStorage{}, messages)
+	uc.SetReportIngestor(newReportIngestor(repo))
+
+	if err := uc.Handle(context.Background(), ProcessInboundEmailInput{
+		Sender:             "friend@example.test",
+		Recipients:         []port.MailboxRecord{{ID: uuid.New()}},
+		RecipientAddresses: []string{"lucas@example.test"},
+		Body:               bytes.NewBufferString("Subject: hello\r\n\r\nhi"),
+	}); err != nil {
+		t.Fatalf("Handle: %v", err)
+	}
+
+	filed := messages.persisted[0]
+	if filed.TargetFolderName == ReportsFolderName {
+		t.Error("ordinary mail was filed as a report")
+	}
+	if filed.AlreadySeen {
+		t.Error("ordinary mail was filed as already read")
+	}
+}
+
+// With no ingestor configured, delivery must behave exactly as it did before
+// this existed - reports included.
+func TestDeliveryIsUnchangedWithoutAnIngestor(t *testing.T) {
+	messages := &recordingMessageRepository{}
+	uc := NewProcessInboundEmailUseCase(nil, &capturingBlobStorage{}, messages)
+
+	payload := messageWithAttachment(googleTlsRptFilename, "application/gzip", gzipped(t, tlsRptJSON))
+	if err := uc.Handle(context.Background(), ProcessInboundEmailInput{
+		Sender:             "smtp-tls-reporting@google.com",
+		Recipients:         []port.MailboxRecord{{ID: uuid.New()}},
+		RecipientAddresses: []string{"tlsrpt@example.test"},
+		Body:               bytes.NewReader(payload),
+	}); err != nil {
+		t.Fatalf("Handle: %v", err)
+	}
+	if messages.persisted[0].TargetFolderName == ReportsFolderName {
+		t.Error("a report was routed with no ingestor configured")
+	}
+}

services/protocols/internal/application/usecase/process_inbound_email.go

@@ -65,12 +65,20 @@ type ProcessInboundEmailUseCase struct {
 	messages       port.InboundMessageRepository
 	folders        port.ImapFolderRepository
 	trackerManager *MailboxTrackerManager
+	reportIngestor *IngestDeliveredReportsUseCase
 }
 
 func NewProcessInboundEmailUseCase(mailboxes port.MailboxRepository, blobs port.BlobStorage, messages port.InboundMessageRepository) *ProcessInboundEmailUseCase {
 	return &ProcessInboundEmailUseCase{mailboxes: mailboxes, blobs: blobs, messages: messages}
 }
 
+// SetReportIngestor enables reading DMARC and TLS-RPT reports out of the mail
+// that carries them. Optional: with no ingestor a report is delivered like any
+// other message, which is what happened before this existed.
+func (uc *ProcessInboundEmailUseCase) SetReportIngestor(ingestor *IngestDeliveredReportsUseCase) {
+	uc.reportIngestor = ingestor
+}
+
 func (uc *ProcessInboundEmailUseCase) SetScanner(scanner port.ContentScanner) {
 	uc.scanner = scanner
 }
@@ -234,6 +242,26 @@ func (uc *ProcessInboundEmailUseCase) Handle(ctx context.Context, input ProcessI
 		}
 	}
 
+	// Reports are read here, after the scan has had its say and before the
+	// message is filed, because this is where the recipient list and the
+	// finished payload are both in hand.
+	//
+	// A report that fails to parse is still routed to Reports: the address it
+	// was sent to is what makes it one, and leaving a broken report in the
+	// inbox instead would put back exactly the noise this removes. The bytes
+	// are kept either way, so it can be re-ingested once the cause is fixed.
+	alreadySeen := false
+	if uc.reportIngestor != nil {
+		outcome, err := uc.reportIngestor.Ingest(ctx, input.RecipientAddresses, payload)
+		if err != nil {
+			return err
+		}
+		if outcome.Kind != ReportKindNone {
+			targetFolder = ReportsFolderName
+			alreadySeen = true
+		}
+	}
+
 	blob, err := uc.blobs.Store(ctx, bytes.NewReader(payload))
 	if err != nil {
 		return err
@@ -261,6 +289,7 @@ func (uc *ProcessInboundEmailUseCase) Handle(ctx context.Context, input ProcessI
 			FromDisplayName:  headers.FromDisplayName,
 			MessageIDHeader:  headers.MessageID,
 			HasAttachments:   headers.HasAttachments,
+			AlreadySeen:      alreadySeen,
 			SPFResult:        authResult.SPF,
 			DKIMResult:       authResult.DKIM,
 			DMARCResult:      authResult.DMARC,