Persist channel DRED settings

PROGRESS.md

@@ -1,6 +1,6 @@
 # VoiceCat status
 
-Updated: 2026-09-20
+Updated: 2026-09-22
 
 ## Current state
 
@@ -25,6 +25,9 @@ verified on an iPhone 16 Pro Max with a two-channel AVAudioEngine input and dist
 samples; the managed Apple binding requires native use of its otherwise-unmapped stereo polar
 pattern constant.
 
+SQLite schema v3 persists channel DRED settings and migrates existing v1/v2 databases with DRED
+disabled until explicitly enabled.
+
 ## Release gates
 
 - Run real multi-person calls on Windows, macOS, and physical iOS hardware, including adaptive

docs/api-dotnet.md

@@ -228,7 +228,8 @@ moves members to Lobby (even if full), clearing their streams. Edits stop existi
 so clients must negotiate the updated audio configuration. Channel names/topics/passwords
 are limited to 128/4096/1024 UTF-8 bytes. Audio requires Opus, 48 kHz, mono/stereo,
 500–512000 bps, integral 5/10/20/40/60 ms frames and valid application/loss/complexity.
-Database v2 has no DRED column; CRUD rejects DRED rather than silently losing it on restart.
+Database v3 persists DRED with the rest of the channel audio configuration. Opening a v1 or v2
+database adds the DRED column with a disabled default before accepting channel updates.
 
 Session permissions gate kick/ban/move/mute and account operations. Only administrators
 can grant permissions; account-administration permission cannot grant administrator status.
@@ -283,7 +284,7 @@ The reaper sends a fatal disconnect, removes presence/routing and broadcasts one
 event. Valid UDP activity keeps a TCP-idle client alive. Shutdown cancels and awaits
 the accept, reaper, control and media loops before disposing credentials/storage.
 
-`AccountStore(path)` uses schema version 2 and accepts version 1 migration,
+`AccountStore(path)` uses schema version 3 and accepts version 1 and 2 migrations,
 and rejects unknown revisions. Opening an existing channel table does not reseed it.
 Account creation/authentication uses parameterized SQL; two password workers bound
 per-store Argon2 work. Failed authentication leaves `last_login` unchanged. Dispose

src/VoiceCat.Server/ChannelManagement.cs

@@ -65,9 +65,9 @@ public sealed partial class VoiceServer
             Encoding.UTF8.GetByteCount(channel.Topic) > 4096 || Encoding.UTF8.GetByteCount(password) > 1024 || !Enum.IsDefined(channel.Type) ||
             channel.MaxUsers > int.MaxValue || a is null || a.Codec != 0 || !Enum.IsDefined(a.Mode) || !Enum.IsDefined(a.Application) ||
             a.SampleRate != 48000 || a.BitrateBps is < 500 or > 512000 || a.FrameMs is not (5 or 10 or 20 or 40 or 60) ||
-            a.Complexity > 10 || a.ExpectedPacketLoss > 100 || a.Dred ||
+            a.Complexity > 10 || a.ExpectedPacketLoss > 100 ||
             !create && !channels.Any(c => c.Id == channel.Id) || channel.ParentId != 0 && !channels.Any(c => c.Id == channel.ParentId))
-            throw new ArgumentException("Invalid channel or audio configuration (database v2 cannot persist DRED).");
+            throw new ArgumentException("Invalid channel or audio configuration.");
         if (channel.Id == 1 && !create && (password.Length != 0 || channel.ParentId != 0)) throw new ArgumentException("Lobby must remain an unprotected root channel.");
         uint parent = channel.ParentId;
         var visited = new HashSet<uint>();

src/VoiceCat.Server/Data/AccountStore.cs

@@ -27,13 +27,21 @@ public sealed partial class AccountStore : IDisposable
         version.Transaction = transaction;
         version.CommandText = "SELECT value FROM server_meta WHERE key='schema_version'";
         object? stored = version.ExecuteScalar();
-        if (stored is not null && (!int.TryParse((string)stored, NumberStyles.None, CultureInfo.InvariantCulture, out int revision) || revision is < 1 or > 2))
+        int revision = 0;
+        if (stored is not null && (!int.TryParse((string)stored, NumberStyles.None, CultureInfo.InvariantCulture, out revision) || revision is < 1 or > 3))
             throw new InvalidDataException("Unsupported server database schema version.");
         using var resource = typeof(AccountStore).Assembly.GetManifestResourceStream("VoiceCat.Server.Data.schema.sql")!;
         using var reader = new StreamReader(resource);
         using var migrate = connection.CreateCommand();
         migrate.Transaction = transaction;
-        migrate.CommandText = reader.ReadToEnd() + "INSERT INTO server_meta (key,value) VALUES ('schema_version','2') ON CONFLICT(key) DO UPDATE SET value='2';";
+        migrate.CommandText = reader.ReadToEnd();
+        migrate.ExecuteNonQuery();
+        if (stored is not null && revision < 3)
+        {
+            migrate.CommandText = "ALTER TABLE channels ADD COLUMN audio_dred INTEGER NOT NULL DEFAULT 0;";
+            migrate.ExecuteNonQuery();
+        }
+        migrate.CommandText = "INSERT INTO server_meta (key,value) VALUES ('schema_version','3') ON CONFLICT(key) DO UPDATE SET value='3';";
         migrate.ExecuteNonQuery();
         transaction.Commit();
     }
@@ -121,7 +129,7 @@ public sealed partial class AccountStore : IDisposable
         command.CommandText = """
             SELECT id,parent_id,name,topic,password_hash,max_users,type,sort_order,
             audio_codec,audio_mode,audio_sample_rate,audio_bitrate_bps,audio_frame_ms,
-            audio_application,audio_fec,audio_expected_packet_loss,audio_dtx,audio_complexity
+            audio_application,audio_fec,audio_expected_packet_loss,audio_dtx,audio_complexity,audio_dred
             FROM channels ORDER BY sort_order,id
             """;
         using var reader = command.ExecuteReader();
@@ -139,7 +147,7 @@ public sealed partial class AccountStore : IDisposable
                     SampleRate = checked((uint)reader.GetInt64(10)), BitrateBps = checked((uint)reader.GetInt64(11)),
                     FrameMs = checked((uint)reader.GetInt64(12)), Application = (Voicecat.V1.OpusApplication)reader.GetInt32(13),
                     Fec = reader.GetInt32(14) != 0, ExpectedPacketLoss = checked((uint)reader.GetInt64(15)),
-                    Dtx = reader.GetInt32(16) != 0, Complexity = checked((uint)reader.GetInt64(17))
+                    Dtx = reader.GetInt32(16) != 0, Complexity = checked((uint)reader.GetInt64(17)), Dred = reader.GetInt32(18) != 0
                 }
             });
         }

src/VoiceCat.Server/Data/ChannelStore.cs

@@ -43,9 +43,9 @@ public sealed partial class AccountStore
             byte[] salt = RandomNumberGenerator.GetBytes(16);
             hash = Convert.ToHexString(salt).ToLowerInvariant() + ":" + Convert.ToHexString(ChannelDigest(password, salt)).ToLowerInvariant();
         }
-        string[] columns = ["parent_id", "name", "topic", "max_users", "type", "sort_order", "audio_codec", "audio_mode", "audio_sample_rate", "audio_bitrate_bps", "audio_frame_ms", "audio_application", "audio_fec", "audio_expected_packet_loss", "audio_dtx", "audio_complexity"];
+        string[] columns = ["parent_id", "name", "topic", "max_users", "type", "sort_order", "audio_codec", "audio_mode", "audio_sample_rate", "audio_bitrate_bps", "audio_frame_ms", "audio_application", "audio_fec", "audio_expected_packet_loss", "audio_dtx", "audio_complexity", "audio_dred"];
         var a = channel.Audio;
-        object[] values = [channel.ParentId, channel.Name, channel.Topic, channel.MaxUsers, (int)channel.Type, channel.Order, a.Codec, (int)a.Mode, a.SampleRate, a.BitrateBps, a.FrameMs, (int)a.Application, a.Fec, a.ExpectedPacketLoss, a.Dtx, a.Complexity];
+        object[] values = [channel.ParentId, channel.Name, channel.Topic, channel.MaxUsers, (int)channel.Type, channel.Order, a.Codec, (int)a.Mode, a.SampleRate, a.BitrateBps, a.FrameMs, (int)a.Application, a.Fec, a.ExpectedPacketLoss, a.Dtx, a.Complexity, a.Dred];
         for (int i = 0; i < columns.Length; i++) command.Parameters.AddWithValue("$" + columns[i], values[i]);
         command.Parameters.AddWithValue("$hash", hash);
         command.Parameters.AddWithValue("$id", channel.Id);

src/VoiceCat.Server/Data/schema.sql

@@ -25,6 +25,7 @@ CREATE TABLE IF NOT EXISTS channels (
     audio_expected_packet_loss INTEGER NOT NULL DEFAULT 10,
     audio_dtx INTEGER NOT NULL DEFAULT 1,
     audio_complexity INTEGER NOT NULL DEFAULT 5,
+    audio_dred INTEGER NOT NULL DEFAULT 0,
     sort_order INTEGER NOT NULL DEFAULT 0
 );
 CREATE TABLE IF NOT EXISTS bans (

tests/VoiceCat.Tests/AccountStoreTests.cs

@@ -54,4 +54,33 @@ public sealed class AccountStoreTests
         }
         finally { Directory.Delete(directory, true); }
     }
+
+    [Fact]
+    public void VersionTwoDatabaseMigratesDredAsDisabled()
+    {
+        string directory = Path.Combine(Path.GetTempPath(), "voicecat-v2-" + Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(directory);
+        string path = Path.Combine(directory, "voicecat.db");
+        try
+        {
+            using (var store = new AccountStore(path)) store.LoadChannels();
+            using (var connection = new SqliteConnection(new SqliteConnectionStringBuilder { DataSource = path, Pooling = false }.ToString()))
+            {
+                connection.Open();
+                using var command = connection.CreateCommand();
+                command.CommandText = "ALTER TABLE channels DROP COLUMN audio_dred; UPDATE server_meta SET value='2' WHERE key='schema_version';";
+                command.ExecuteNonQuery();
+            }
+
+            using (var migrated = new AccountStore(path))
+                Assert.All(migrated.LoadChannels(), channel => Assert.False(channel.Audio.Dred));
+
+            using var verify = new SqliteConnection(new SqliteConnectionStringBuilder { DataSource = path, Pooling = false }.ToString());
+            verify.Open();
+            using var query = verify.CreateCommand();
+            query.CommandText = "SELECT value FROM server_meta WHERE key='schema_version'";
+            Assert.Equal("3", query.ExecuteScalar());
+        }
+        finally { Directory.Delete(directory, true); }
+    }
 }

tests/VoiceCat.Tests/ChannelManagementTests.cs

@@ -99,4 +99,33 @@ public class ChannelManagementTests
         Assert.True(await ResultAsync(admin, new() { DeleteChannel = new() { ChannelId = child.Id } }));
         Assert.True(await ResultAsync(admin, new() { DeleteChannel = new() { ChannelId = parent.Id } }));
     }
+
+    [Fact]
+    public async Task DredAudioSettingsRoundTripThroughEditAndDatabaseRestart()
+    {
+        await using var fixture = new ServerFixture();
+        await using var admin = await AdminAsync(fixture);
+        using (var store = new AccountStore(Path.Combine(fixture.Directory, "voicecat.db")))
+        {
+            Channel music = store.LoadChannels().Single(c => c.Name == "Music Room");
+            music.Audio.SampleRate = 48_000;
+            music.Audio.BitrateBps = 128_000;
+            music.Audio.ExpectedPacketLoss = 15;
+            music.Audio.Dtx = true;
+            music.Audio.Fec = true;
+            music.Audio.Dred = true;
+            music.Audio.Complexity = 10;
+            Assert.True(await ResultAsync(admin, new() { EditChannel = new() { Channel = music } }));
+        }
+
+        using var reopened = new AccountStore(Path.Combine(fixture.Directory, "voicecat.db"));
+        AudioConfig audio = reopened.LoadChannels().Single(c => c.Name == "Music Room").Audio;
+        Assert.Equal(48_000U, audio.SampleRate);
+        Assert.Equal(128_000U, audio.BitrateBps);
+        Assert.Equal(15U, audio.ExpectedPacketLoss);
+        Assert.True(audio.Dtx);
+        Assert.True(audio.Fec);
+        Assert.True(audio.Dred);
+        Assert.Equal(10U, audio.Complexity);
+    }
 }

tests/VoiceCat.Tests/WindowsManagedClientTests.cs

@@ -78,6 +78,25 @@ public class WindowsManagedClientTests
         Assert.Empty(alice.ManagedClient.LocalStreams);
     }
 
+    [Fact]
+    public async Task WindowsChannelEditorSettingsRoundTripFromServer()
+    {
+        await using var fixture = new ServerFixture();
+        using (var accounts = new AccountStore(Path.Combine(fixture.Directory, "voicecat.db")))
+            await accounts.CreateAccountAsync("Admin", "secret", true);
+        using var client = new Client("Admin", "test", tofuStorePath: Path.Combine(fixture.Directory, "admin.pins"));
+        await Login(client, fixture, true);
+        ChannelInfo music = client.ListChannels().Single(c => c.Name == "Music Room");
+        var expected = new AudioConfigInfo(0, true, 48_000, 128_000, 20, 1, true, 15, true, 10, true);
+        var edit = new ChannelEditInfo(music.Id, music.ParentId, music.Name, music.Topic,
+            music.PasswordProtected, null, music.MaxUsers, music.SortOrder, expected);
+
+        Assert.Equal(VcResult.Ok, client.EditChannel(edit));
+        await Until(client, () => client.ListChannels().Single(c => c.Id == music.Id).Audio.Dred);
+
+        Assert.Equal(expected, client.ListChannels().Single(c => c.Id == music.Id).Audio);
+    }
+
     [Fact]
     public async Task WindowsScreenAudioPreservesDistinctStereoChannels()
     {