imapserver: Add CONDSTORE extension support

imapclient/client_test.go

@@ -102,6 +102,7 @@ func newMemClientServerPair(t *testing.T) (net.Conn, io.Closer) {
 		Caps: imap.CapSet{
 			imap.CapIMAP4rev1: {},
 			imap.CapIMAP4rev2: {},
+			imap.CapCondStore: {},
 		},
 	})
 

imapclient/condstore_test.go

@@ -0,0 +1,311 @@
+package imapclient_test
+
+import (
+	"testing"
+
+	"github.com/emersion/go-imap/v2"
+)
+
+func TestSelect_CondStore(t *testing.T) {
+	client, server := newClientServerPair(t, imap.ConnStateAuthenticated)
+	defer client.Close()
+	defer server.Close()
+
+	// Test SELECT with CONDSTORE parameter
+	options := &imap.SelectOptions{
+		CondStore: true,
+	}
+	data, err := client.Select("INBOX", options).Wait()
+	if err != nil {
+		t.Fatalf("Select() with CONDSTORE = %v", err)
+	}
+
+	// Verify that HighestModSeq is returned
+	if data.HighestModSeq == 0 {
+		t.Errorf("SelectData.HighestModSeq is 0, expected non-zero value when CONDSTORE is enabled")
+	}
+	t.Logf("Mailbox HIGHESTMODSEQ: %d", data.HighestModSeq)
+}
+
+func TestFetch_ModSeq(t *testing.T) {
+	client, server := newClientServerPair(t, imap.ConnStateSelected)
+	defer client.Close()
+	defer server.Close()
+
+	// Test FETCH with MODSEQ item
+	seqSet := imap.SeqSetNum(1)
+	fetchOptions := &imap.FetchOptions{
+		ModSeq: true,
+	}
+	messages, err := client.Fetch(seqSet, fetchOptions).Collect()
+	if err != nil {
+		t.Fatalf("Fetch() with MODSEQ = %v", err)
+	} else if len(messages) != 1 {
+		t.Fatalf("len(messages) = %v, want 1", len(messages))
+	}
+
+	msg := messages[0]
+	if msg.ModSeq == 0 {
+		t.Errorf("msg.ModSeq is 0, expected non-zero value")
+	}
+	t.Logf("Message MODSEQ: %d", msg.ModSeq)
+}
+
+func TestFetch_ChangedSince(t *testing.T) {
+	client, server := newClientServerPair(t, imap.ConnStateSelected)
+	defer client.Close()
+	defer server.Close()
+
+	// First, get current ModSeq
+	seqSet := imap.SeqSetNum(1)
+	firstFetch, err := client.Fetch(seqSet, &imap.FetchOptions{
+		ModSeq: true,
+	}).Collect()
+	if err != nil {
+		t.Fatalf("Initial Fetch() = %v", err)
+	}
+	currentModSeq := firstFetch[0].ModSeq
+	t.Logf("Initial ModSeq: %d", currentModSeq)
+
+	// Now fetch with CHANGEDSINCE using the current ModSeq
+	// This should return no messages since nothing has changed
+	fetchOptions := &imap.FetchOptions{
+		Flags:        true,
+		ChangedSince: currentModSeq,
+	}
+	messages, err := client.Fetch(seqSet, fetchOptions).Collect()
+	if err != nil {
+		t.Fatalf("Fetch() with CHANGEDSINCE = %v", err)
+	}
+
+	// No messages should be returned since nothing has changed
+	if len(messages) != 0 {
+		t.Errorf("Fetch() with CHANGEDSINCE returned %d messages, want 0", len(messages))
+	}
+
+	// Now modify the message
+	storeFlags := imap.StoreFlags{
+		Op:    imap.StoreFlagsAdd,
+		Flags: []imap.Flag{imap.FlagSeen},
+	}
+	storeCmd := client.Store(seqSet, &storeFlags, nil)
+	storeResults, err := storeCmd.Collect()
+	if err != nil {
+		t.Fatalf("Store() = %v", err)
+	}
+	t.Logf("Store results: %d messages", len(storeResults))
+
+	// Fetch the current ModSeq again to verify it changed
+	secondFetch, err := client.Fetch(seqSet, &imap.FetchOptions{
+		ModSeq: true,
+	}).Collect()
+	if err != nil {
+		t.Fatalf("Second Fetch() = %v", err)
+	}
+	newModSeq := secondFetch[0].ModSeq
+	t.Logf("New ModSeq after flag change: %d", newModSeq)
+
+	// Now fetch again with the old modseq - should return the message
+	messages, err = client.Fetch(seqSet, fetchOptions).Collect()
+	if err != nil {
+		t.Fatalf("Fetch() with CHANGEDSINCE after change = %v", err)
+	}
+	t.Logf("Messages returned after change: %d", len(messages))
+	if len(messages) != 1 {
+		t.Errorf("Fetch() with CHANGEDSINCE after change returned %d messages, want 1", len(messages))
+	}
+}
+
+func TestStore_UnchangedSince(t *testing.T) {
+	client, server := newClientServerPair(t, imap.ConnStateSelected)
+	defer client.Close()
+	defer server.Close()
+
+	// First, get current ModSeq
+	seqSet := imap.SeqSetNum(1)
+	firstFetch, err := client.Fetch(seqSet, &imap.FetchOptions{
+		ModSeq: true,
+	}).Collect()
+	if err != nil {
+		t.Fatalf("Initial Fetch() = %v", err)
+	}
+	currentModSeq := firstFetch[0].ModSeq
+
+	// Now modify the message using UNCHANGEDSINCE with the current ModSeq
+	// This should succeed because the message hasn't been modified
+	storeFlags := imap.StoreFlags{
+		Op:    imap.StoreFlagsAdd,
+		Flags: []imap.Flag{imap.FlagSeen},
+	}
+	storeOptions := &imap.StoreOptions{
+		UnchangedSince: currentModSeq,
+	}
+	messages, err := client.Store(seqSet, &storeFlags, storeOptions).Collect()
+	if err != nil {
+		t.Fatalf("Store() with UNCHANGEDSINCE = %v", err)
+	}
+	if len(messages) != 1 {
+		t.Errorf("Store() with UNCHANGEDSINCE returned %d messages, want 1", len(messages))
+	}
+
+	// Get the new ModSeq
+	secondFetch, err := client.Fetch(seqSet, &imap.FetchOptions{
+		ModSeq: true,
+	}).Collect()
+	if err != nil {
+		t.Fatalf("Second Fetch() = %v", err)
+	}
+	newModSeq := secondFetch[0].ModSeq
+
+	// The ModSeq should have increased
+	if newModSeq <= currentModSeq {
+		t.Errorf("ModSeq after update = %d, want > %d", newModSeq, currentModSeq)
+	}
+
+	// Try to modify again with the old ModSeq
+	// This should not modify the message because it has changed since
+	storeFlags = imap.StoreFlags{
+		Op:    imap.StoreFlagsAdd,
+		Flags: []imap.Flag{imap.FlagDeleted},
+	}
+	storeOptions = &imap.StoreOptions{
+		UnchangedSince: currentModSeq, // Use the old ModSeq
+	}
+	messages, err = client.Store(seqSet, &storeFlags, storeOptions).Collect()
+	if err != nil {
+		t.Fatalf("Second Store() with UNCHANGEDSINCE = %v", err)
+	}
+
+	// The operation should not have modified any messages
+	if len(messages) != 0 {
+		t.Errorf("Second Store() with UNCHANGEDSINCE returned %d messages, should be 0", len(messages))
+	}
+}
+func TestStatus_HighestModSeq(t *testing.T) {
+	client, server := newClientServerPair(t, imap.ConnStateAuthenticated)
+	defer client.Close()
+	defer server.Close()
+
+	// Test STATUS with HIGHESTMODSEQ parameter
+	options := &imap.StatusOptions{
+		HighestModSeq: true,
+	}
+	data, err := client.Status("INBOX", options).Wait()
+	if err != nil {
+		t.Fatalf("Status() with HIGHESTMODSEQ = %v", err)
+	}
+
+	// Verify that HighestModSeq is returned
+	if data.HighestModSeq == 0 {
+		t.Errorf("StatusData.HighestModSeq is 0, expected non-zero value")
+	}
+	t.Logf("Mailbox HIGHESTMODSEQ from STATUS: %d", data.HighestModSeq)
+}
+
+func TestSearch_ModSeq(t *testing.T) {
+	client, server := newClientServerPair(t, imap.ConnStateSelected)
+	defer client.Close()
+	defer server.Close()
+
+	// First, get current ModSeq for our message
+	seqSet := imap.SeqSetNum(1)
+	firstFetch, err := client.Fetch(seqSet, &imap.FetchOptions{
+		ModSeq: true,
+	}).Collect()
+	if err != nil {
+		t.Fatalf("Initial Fetch() = %v", err)
+	}
+	currentModSeq := firstFetch[0].ModSeq
+	t.Logf("Initial ModSeq: %d", currentModSeq)
+
+	// Now search with MODSEQ criterion using a value lower than current
+	// This should find the message
+	searchCriteria := &imap.SearchCriteria{
+		ModSeq: &imap.SearchCriteriaModSeq{
+			ModSeq: currentModSeq - 1,
+		},
+	}
+	searchOptions := &imap.SearchOptions{
+		ReturnCount: true,
+	}
+	results, err := client.Search(searchCriteria, searchOptions).Wait()
+	if err != nil {
+		t.Fatalf("Search with MODSEQ = %v", err)
+	}
+
+	// There should be one message that matches
+	if results.Count != 1 {
+		t.Errorf("Search with MODSEQ < current returned %d messages, want 1", results.Count)
+	}
+
+	// Now search with MODSEQ criterion using current value
+	// This should find the message (since MODSEQ criterion is >= not >)
+	searchCriteria = &imap.SearchCriteria{
+		ModSeq: &imap.SearchCriteriaModSeq{
+			ModSeq: currentModSeq,
+		},
+	}
+	results, err = client.Search(searchCriteria, searchOptions).Wait()
+	if err != nil {
+		t.Fatalf("Search with MODSEQ = %v", err)
+	}
+
+	// There should be one message that matches
+	if results.Count != 1 {
+		t.Errorf("Search with MODSEQ = current returned %d messages, want 1", results.Count)
+	}
+
+	// Now search with MODSEQ criterion using a higher value
+	// This should NOT find the message
+	searchCriteria = &imap.SearchCriteria{
+		ModSeq: &imap.SearchCriteriaModSeq{
+			ModSeq: currentModSeq + 1,
+		},
+	}
+	results, err = client.Search(searchCriteria, searchOptions).Wait()
+	if err != nil {
+		t.Fatalf("Search with MODSEQ = %v", err)
+	}
+
+	// There should be no messages that match
+	if results.Count != 0 {
+		t.Errorf("Search with MODSEQ > current returned %d messages, want 0", results.Count)
+	}
+}
+
+func TestCapability_CondStore(t *testing.T) {
+	client, server := newClientServerPair(t, imap.ConnStateNotAuthenticated)
+	defer client.Close()
+	defer server.Close()
+
+	// Check capabilities after connecting
+	capCmd := client.Capability()
+	caps, err := capCmd.Wait()
+	if err != nil {
+		t.Fatalf("Capability() = %v", err)
+	}
+
+	_, hasCondStore := caps[imap.CapCondStore]
+	if hasCondStore {
+		t.Errorf("CapCondStore should not be available before authentication")
+	}
+
+	// Login
+	if err := client.Login(testUsername, testPassword).Wait(); err != nil {
+		t.Fatalf("Login() = %v", err)
+	}
+
+	// Check capabilities after login
+	capCmd = client.Capability()
+	caps, err = capCmd.Wait()
+	if err != nil {
+		t.Fatalf("Capability() after login = %v", err)
+	}
+
+	_, hasCondStore = caps[imap.CapCondStore]
+	if !hasCondStore {
+		t.Errorf("CapCondStore should be available after authentication")
+	} else {
+		t.Logf("CONDSTORE capability correctly announced after authentication")
+	}
+}

imapserver/capability.go

@@ -91,6 +91,7 @@ func (c *Conn) availableCaps() []imap.Cap {
 			imap.CapCreateSpecialUse,
 			imap.CapLiteralPlus,
 			imap.CapUnauthenticate,
+			imap.CapCondStore,
 		})
 	}
 	return caps

imapserver/fetch.go

@@ -75,6 +75,26 @@ func (c *Conn) handleFetch(dec *imapwire.Decoder, numKind NumKind) error {
 		}
 	}
 
+	if dec.SP() && dec.Special('(') {
+		var param string
+		if !dec.ExpectAtom(&param) {
+			return dec.Err()
+		}
+
+		if strings.ToUpper(param) == "CHANGEDSINCE" {
+			if !dec.ExpectSP() || !dec.ExpectModSeq(&options.ChangedSince) {
+				return dec.Err()
+			}
+			options.ModSeq = true
+		} else {
+			return fmt.Errorf("unknown FETCH modifier: %v", param)
+		}
+
+		if !dec.ExpectSpecial(')') {
+			return dec.Err()
+		}
+	}
+
 	if !dec.ExpectCRLF() {
 		return dec.Err()
 	}
@@ -108,6 +128,8 @@ func handleFetchAtt(dec *imapwire.Decoder, attName string, options *imap.FetchOp
 		options.RFC822Size = true
 	case "UID":
 		options.UID = true
+	case "MODSEQ":
+		options.ModSeq = true
 	case "RFC822": // equivalent to BODY[]
 		bs := &imap.FetchItemBodySection{}
 		writerOptions.obsolete[bs] = attName
@@ -456,6 +478,12 @@ func (w *FetchResponseWriter) WriteEnvelope(envelope *imap.Envelope) {
 	writeEnvelope(enc, envelope)
 }
 
+// WriteModSeq writes the message's MODSEQ.
+func (w *FetchResponseWriter) WriteModSeq(modSeq uint64) {
+	w.writeItemSep()
+	w.enc.Atom("MODSEQ").SP().Special('(').ModSeq(modSeq).Special(')')
+}
+
 // WriteBodyStructure writes the message's body structure (either BODYSTRUCTURE
 // or BODY).
 func (w *FetchResponseWriter) WriteBodyStructure(bs imap.BodyStructure) {