feat(server): lossy avatar thumbnails, gzip upload and separate avatar endpoints

server/src/WebDrop.Storage/SqliteAccountProfiles.cs

@@ -9,24 +9,27 @@ public sealed partial class SqliteAccountStore
         lock (_gate)
         {
             using var cmd = _connection.CreateCommand();
-            cmd.CommandText = "SELECT display_name,avatar,modified_at FROM account_profiles WHERE username=$u";
+            cmd.CommandText = "SELECT display_name,avatar,modified_at,avatar_thumb FROM account_profiles WHERE username=$u";
             cmd.Parameters.AddWithValue("$u", username);
             using var reader = cmd.ExecuteReader();
-            return reader.Read() ? new AccountProfile { Username = username, DisplayName = reader.GetString(0), Avatar = reader.IsDBNull(1) ? null : reader.GetString(1), ModifiedAt = reader.GetInt64(2) }
+            return reader.Read() ? new AccountProfile { Username = username, DisplayName = reader.GetString(0), Avatar = reader.IsDBNull(1) ? null : reader.GetString(1), HasAvatar = !reader.IsDBNull(1), ModifiedAt = reader.GetInt64(2), AvatarThumb = reader.IsDBNull(3) ? null : reader.GetString(3) }
                 : new AccountProfile { Username = username, DisplayName = username, ModifiedAt = 0 };
         }
     }
-    public AccountProfile UpdateProfile(string username, string displayName, string? avatar)
+    public AccountProfile UpdateProfile(string username, string displayName, string? avatar, string? avatarThumb = null, bool keepAvatar = false)
     {
         if (displayName is null || displayName.Trim().Length > 48 || displayName.Any(char.IsControl)) throw new WebDropException(ErrorCode.BadRequest);
-        if (avatar is not null) AvatarData.Validate(avatar, AvatarData.MaxAccountGifChars);
+        if (keepAvatar) { var current = Profile(username); avatar = current.Avatar; avatarThumb = current.AvatarThumb; }
+        else if (avatar is not null) AvatarData.Validate(avatar, AvatarData.MaxAccountGifChars);
+        if (!keepAvatar && avatarThumb is not null) { if (avatar is null) throw new WebDropException(ErrorCode.BadRequest); AvatarData.ValidateThumb(avatarThumb); }
         lock (_gate)
         {
             using var cmd = _connection.CreateCommand();
-            cmd.CommandText = "INSERT INTO account_profiles(username,display_name,avatar,modified_at) VALUES($u,$n,$a,$t) ON CONFLICT(username) DO UPDATE SET display_name=excluded.display_name,avatar=excluded.avatar,modified_at=MAX(account_profiles.modified_at+1,excluded.modified_at)";
+            cmd.CommandText = "INSERT INTO account_profiles(username,display_name,avatar,avatar_thumb,modified_at) VALUES($u,$n,$a,$b,$t) ON CONFLICT(username) DO UPDATE SET display_name=excluded.display_name,avatar=excluded.avatar,avatar_thumb=excluded.avatar_thumb,modified_at=MAX(account_profiles.modified_at+1,excluded.modified_at)";
             cmd.Parameters.AddWithValue("$u", username);
             cmd.Parameters.AddWithValue("$n", displayName.Trim());
             cmd.Parameters.AddWithValue("$a", (object?)avatar ?? DBNull.Value);
+            cmd.Parameters.AddWithValue("$b", (object?)avatarThumb ?? DBNull.Value);
             cmd.Parameters.AddWithValue("$t", DateTimeOffset.UtcNow.ToUnixTimeMilliseconds());
             cmd.ExecuteNonQuery();
             return Profile(username);

server/src/WebDrop.Storage/SqliteAccountStore.cs

@@ -27,6 +27,19 @@ public sealed partial class SqliteAccountStore : IDisposable
         cmd.ExecuteNonQuery();
         using (var columns = _connection.CreateCommand())
         {
+            columns.CommandText = "PRAGMA table_info(account_profiles)";
+            using (var profileColumns = columns.ExecuteReader())
+            {
+                bool hasThumb = false;
+                while (profileColumns.Read()) if (profileColumns.GetString(1) == "avatar_thumb") hasThumb = true;
+                profileColumns.Close();
+                if (!hasThumb)
+                {
+                    using var alterProfiles = _connection.CreateCommand();
+                    alterProfiles.CommandText = "ALTER TABLE account_profiles ADD COLUMN avatar_thumb TEXT";
+                    alterProfiles.ExecuteNonQuery();
+                }
+            }
             columns.CommandText = "PRAGMA table_info(accounts)";
             using var reader = columns.ExecuteReader();
             bool hasSigningKey = false;

server/src/WebDrop.Storage/SqliteChannelStore.cs

@@ -37,6 +37,7 @@ public sealed class SqliteChannelStore : IResourceStore, IDisposable
         Exec(_writeConn, "DELETE FROM channel_join_denials WHERE target LIKE 'endpoint:%';");
         // v7: 设置里的成员人数上限由 seats 改名为 max_members,迁移已有频道的设置 JSON(幂等)
         Exec(_writeConn, "UPDATE channels SET settings = json_remove(json_set(settings, '$.max_members', json_extract(settings, '$.seats')), '$.seats') WHERE json_extract(settings, '$.seats') IS NOT NULL AND json_extract(settings, '$.max_members') IS NULL;");
+        try { Exec(_writeConn, "ALTER TABLE channel_avatars ADD COLUMN thumb TEXT;"); } catch (SqliteException) { /* 新建的表或已经迁移过 */ }
         // Additive table: retain the running v2 database and its existing channel data.
         Exec(_writeConn, """
             CREATE TABLE IF NOT EXISTS channel_key_packages (
@@ -46,7 +47,7 @@ public sealed class SqliteChannelStore : IResourceStore, IDisposable
             CREATE INDEX IF NOT EXISTS ix_channel_keys_username ON channel_key_packages(username);
             CREATE TABLE IF NOT EXISTS workspace_structures (space_id BLOB PRIMARY KEY, state TEXT NOT NULL) WITHOUT ROWID;
             CREATE TABLE IF NOT EXISTS workspace_crypto (space_id BLOB PRIMARY KEY, state TEXT NOT NULL) WITHOUT ROWID;
-            CREATE TABLE IF NOT EXISTS channel_avatars (space_id BLOB PRIMARY KEY, avatar TEXT NOT NULL) WITHOUT ROWID;
+            CREATE TABLE IF NOT EXISTS channel_avatars (space_id BLOB PRIMARY KEY, avatar TEXT NOT NULL, thumb TEXT) WITHOUT ROWID;
             """);
     }
 
@@ -508,12 +509,13 @@ public sealed class SqliteChannelStore : IResourceStore, IDisposable
             Run("DELETE FROM channel_join_denials WHERE channel_id=@c", ("@c", key));
         }
 
-        public string? GetChannelAvatar(Id16 id) => Scalar("SELECT avatar FROM channel_avatars WHERE space_id=@c", ("@c", id.ToArray())) as string;
+        public string? GetChannelAvatar(Id16 id, bool thumb) =>
+            Scalar(thumb ? "SELECT COALESCE(thumb, avatar) FROM channel_avatars WHERE space_id=@c" : "SELECT avatar FROM channel_avatars WHERE space_id=@c", ("@c", id.ToArray())) as string;
 
-        public void SetChannelAvatar(Id16 id, string? avatar)
+        public void SetChannelAvatar(Id16 id, string? avatar, string? thumb)
         {
             if (avatar is null) Run("DELETE FROM channel_avatars WHERE space_id=@c", ("@c", id.ToArray()));
-            else Run("INSERT INTO channel_avatars (space_id, avatar) VALUES (@c,@a) ON CONFLICT(space_id) DO UPDATE SET avatar=excluded.avatar", ("@c", id.ToArray()), ("@a", avatar));
+            else Run("INSERT INTO channel_avatars (space_id, avatar, thumb) VALUES (@c,@a,@t) ON CONFLICT(space_id) DO UPDATE SET avatar=excluded.avatar, thumb=excluded.thumb", ("@c", id.ToArray()), ("@a", avatar), ("@t", (object?)thumb ?? DBNull.Value));
         }
 
         public IReadOnlyList<Id16> ListExpiredChannels(long now, int limit) =>