Stream messages to viewer using JSON lines

app/Resources/Viewer/scripts/bootstrap.mjs

@@ -36,18 +36,69 @@ document.addEventListener("DOMContentLoaded", () => {
 		gui.scrollMessagesToTop();
 	});
 	
+	async function fetchUrl(path, contentType) {
+		const response = await fetch("/" + path + "?token=" + encodeURIComponent(window.DHT_SERVER_TOKEN) + "&session=" + encodeURIComponent(window.DHT_SERVER_SESSION), {
+			method: "GET",
+			headers: {
+				"Content-Type": contentType,
+			},
+			credentials: "omit",
+			redirect: "error",
+		});
+		
+		if (!response.ok) {
+			throw "Unexpected response status: " + response.statusText;
+		}
+		
+		return response;
+	}
+	
+	async function processLines(response, callback) {
+		let body = "";
+		
+		for await (const chunk of response.body.pipeThrough(new TextDecoderStream("utf-8"))) {
+			body += chunk;
+			
+			let startIndex = 0;
+			
+			while (true) {
+				const endIndex = body.indexOf("\n", startIndex);
+				if (endIndex === -1) {
+					break;
+				}
+				
+				callback(body.substring(startIndex, endIndex));
+				startIndex = endIndex + 1;
+			}
+			
+			body = body.substring(startIndex);
+		}
+		
+		if (body !== "") {
+			callback(body);
+		}
+	}
+	
 	async function loadData() {
 		try {
-			const response = await fetch("/get-viewer-data?token=" + encodeURIComponent(window.DHT_SERVER_TOKEN) + "&session=" + encodeURIComponent(window.DHT_SERVER_SESSION), {
+			const metadataResponse = await fetchUrl("get-viewer-metadata", "application/json");
-				method: "GET",
+			const metadataJson = await metadataResponse.json();
-				headers: {
+			
-					"Content-Type": "application/json",
+			const messagesResponse = await fetchUrl("get-viewer-messages", "application/x-ndjson");
-				},
+			const messages = {};
-				credentials: "omit",
+			
-				redirect: "error",
+			await processLines(messagesResponse, line => {
+				const message = JSON.parse(line);
+				const channel = message.c;
+				
+				const channelMessages = messages[channel] || (messages[channel] = {});
+				channelMessages[message.id] = message;
+				
+				delete message.id;
+				delete message.c;
 			});
 			
-			state.uploadFile(await response.json());
+			state.uploadFile(metadataJson, messages);
 		} catch (e) {
 			console.error(e);
 			alert("Could not load data, see console for details.");

app/Resources/Viewer/scripts/state.mjs

@@ -6,8 +6,7 @@ export default (function() {
 	/**
 	 * @type {{}}
 	 * @property {{}} users
-	 * @property {String[]} userindex
+	 * @property {{}} servers
-	 * @property {{}[]} servers
 	 * @property {{}} channels
 	 */
 	let loadedFileMeta;
@@ -20,20 +19,16 @@ export default (function() {
 	let currentPage;
 	let messagesPerPage;
 	
-	const getUser = function(index) {
+	const getUser = function(id) {
-		return loadedFileMeta.users[loadedFileMeta.userindex[index]] || { "name": "<unknown>" };
+		return loadedFileMeta.users[id] || { "name": "<unknown>" };
-	};
-	
-	const getUserId = function(index) {
-		return loadedFileMeta.userindex[index];
 	};
 	
 	const getUserList = function() {
 		return loadedFileMeta ? loadedFileMeta.users : [];
 	};
 	
-	const getServer = function(index) {
+	const getServer = function(id) {
-		return loadedFileMeta.servers[index] || { "name": "<unknown>", "type": "unknown" };
+		return loadedFileMeta.servers[id] || { "name": "<unknown>", "type": "unknown" };
 	};
 	
 	const generateChannelHierarchy = function() {
@@ -207,7 +202,7 @@ export default (function() {
 			 */
 			const message = messages[key];
 			const user = getUser(message.u);
-			const avatar = user.avatar ? { id: getUserId(message.u), path: user.avatar } : null;
+			const avatar = user.avatar ? { id: message.u, path: user.avatar } : null;
 			
 			const obj = {
 				user,
@@ -235,7 +230,7 @@ export default (function() {
 			if ("r" in message) {
 				const replyMessage = getMessageById(message.r);
 				const replyUser = replyMessage ? getUser(replyMessage.u) : null;
-				const replyAvatar = replyUser && replyUser.avatar ? { id: getUserId(replyMessage.u), path: replyUser.avatar } : null;
+				const replyAvatar = replyUser && replyUser.avatar ? { id: replyMessage.u, path: replyUser.avatar } : null;
 				
 				obj["reply"] = replyMessage ? {
 					"id": message.r,
@@ -293,20 +288,17 @@ export default (function() {
 			eventOnUsersRefreshed = callback;
 		},
 		
-		/**
+		uploadFile(meta, data) {
-		 * @param {{ meta, data }} file
-		 */
-		uploadFile(file) {
 			if (loadedFileMeta != null) {
 				throw "A file is already loaded!";
 			}
 			
-			if (!file || typeof file.meta !== "object" || typeof file.data !== "object") {
+			if (typeof meta !== "object" || typeof data !== "object") {
 				throw "Invalid file format!";
 			}
 			
-			loadedFileMeta = file.meta;
+			loadedFileMeta = meta;
-			loadedFileData = file.data;
+			loadedFileData = data;
 			loadedMessages = null;
 			
 			selectedChannel = null;

app/Server/Database/Export/Snowflake.cs

@@ -1,3 +1,5 @@
 namespace DHT.Server.Database.Export;
 
-readonly record struct Snowflake(ulong Id);
+readonly record struct Snowflake(ulong Id) {
+	public static implicit operator Snowflake(ulong id) => new (id);
+}

app/Server/Database/Export/ViewerJson.cs

@@ -3,14 +3,10 @@ using System.Text.Json.Serialization;
 
 namespace DHT.Server.Database.Export;
 
-sealed class ViewerJson {
+static class ViewerJson {
-	public required JsonMeta Meta { get; init; }
-	public required Dictionary<Snowflake, Dictionary<Snowflake, JsonMessage>> Data { get; init; }
-
 	public sealed class JsonMeta {
 		public required Dictionary<Snowflake, JsonUser> Users { get; init; }
-		public required List<Snowflake> Userindex { get; init; }
+		public required Dictionary<Snowflake, JsonServer> Servers { get; init; }
-		public required List<JsonServer> Servers { get; init; }
 		public required Dictionary<Snowflake, JsonChannel> Channels { get; init; }
 	}
 	
@@ -30,7 +26,7 @@ sealed class ViewerJson {
 	}
 
 	public sealed class JsonChannel {
-		public required int Server { get; init; }
+		public required Snowflake Server { get; init; }
 		public required string Name { get; init; }
 		
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
@@ -47,7 +43,9 @@ sealed class ViewerJson {
 	}
 
 	public sealed class JsonMessage {
-		public required int U { get; init; }
+		public required Snowflake Id { get; init; }
+		public required Snowflake C { get; init; }
+		public required Snowflake U { get; init; }
 		public required long T { get; init; }
 
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]

app/Server/Database/Export/ViewerJsonExport.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Runtime.CompilerServices;
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
@@ -14,106 +15,90 @@ namespace DHT.Server.Database.Export;
 static class ViewerJsonExport {
 	private static readonly Log Log = Log.ForType(typeof(ViewerJsonExport));
 
-	public static async Task Generate(Stream stream, IDatabaseFile db, MessageFilter? filter = null, CancellationToken cancellationToken = default) {
+	public static async Task GetMetadata(Stream stream, IDatabaseFile db, MessageFilter? filter = null, CancellationToken cancellationToken = default) {
 		var perf = Log.Start();
 
-		var includedUserIds = new HashSet<ulong>();
+		var includedChannels = new List<Channel>();
-		var includedChannelIds = new HashSet<ulong>();
 		var includedServerIds = new HashSet<ulong>();
 
-		var includedMessages = await db.Messages.Get(filter, cancellationToken).ToListAsync(cancellationToken);
+		var channelIdFilter = filter?.ChannelIds;
-		var includedChannels = new List<Channel>();
-
-		foreach (var message in includedMessages) {
-			includedUserIds.Add(message.Sender);
-			includedChannelIds.Add(message.Channel);
-		}
 
 		await foreach (var channel in db.Channels.Get(cancellationToken)) {
-			if (includedChannelIds.Contains(channel.Id)) {
+			if (channelIdFilter == null || channelIdFilter.Contains(channel.Id)) {
 				includedChannels.Add(channel);
 				includedServerIds.Add(channel.Server);
 			}
 		}
 
-		var (users, userIndex, userIndices) = await GenerateUserList(db, includedUserIds);
+		var users = await GenerateUserList(db, cancellationToken);
-		var (servers, serverIndices) = await GenerateServerList(db, includedServerIds);
+		var servers = await GenerateServerList(db, includedServerIds, cancellationToken);
-		var channels = GenerateChannelList(includedChannels, serverIndices);
+		var channels = GenerateChannelList(includedChannels);
+
+		var meta = new ViewerJson.JsonMeta {
+			Users = users,
+			Servers = servers,
+			Channels = channels
+		};
 
 		perf.Step("Collect database data");
 
-		var value = new ViewerJson {
+		await JsonSerializer.SerializeAsync(stream, meta, ViewerJsonMetadataContext.Default.JsonMeta, cancellationToken);
-			Meta = new ViewerJson.JsonMeta {
-				Users = users,
-				Userindex = userIndex,
-				Servers = servers,
-				Channels = channels
-			},
-			Data = GenerateMessageList(includedMessages, userIndices)
-		};
-
-		perf.Step("Generate value object");
-
-		await JsonSerializer.SerializeAsync(stream, value, ViewerJsonContext.Default.ViewerJson, cancellationToken);
 
 		perf.Step("Serialize to JSON");
 		perf.End();
 	}
 
-	private static async Task<(Dictionary<Snowflake, ViewerJson.JsonUser> Users, List<Snowflake> UserIndex, Dictionary<ulong, int> UserIndices)> GenerateUserList(IDatabaseFile db, HashSet<ulong> userIds) {
+	public static async Task GetMessages(Stream stream, IDatabaseFile db, MessageFilter? filter = null, CancellationToken cancellationToken = default) {
+		var perf = Log.Start();
+
+		ReadOnlyMemory<byte> newLine = "\n"u8.ToArray();
+		
+		await foreach(var message in GenerateMessageList(db, filter, cancellationToken)) {
+			await JsonSerializer.SerializeAsync(stream, message, ViewerJsonMessageContext.Default.JsonMessage, cancellationToken);
+			await stream.WriteAsync(newLine, cancellationToken);
+		}
+
+		perf.Step("Generate and serialize messages to JSON");
+		perf.End();
+	}
+
+	private static async Task<Dictionary<Snowflake, ViewerJson.JsonUser>> GenerateUserList(IDatabaseFile db, CancellationToken cancellationToken) {
 		var users = new Dictionary<Snowflake, ViewerJson.JsonUser>();
-		var userIndex = new List<Snowflake>();
-		var userIndices = new Dictionary<ulong, int>();
 
-		await foreach (var user in db.Users.Get()) {
+		await foreach (var user in db.Users.Get(cancellationToken)) {
-			var id = user.Id;
+			users[user.Id] = new ViewerJson.JsonUser {
-			if (!userIds.Contains(id)) {
-				continue;
-			}
-
-			var idSnowflake = new Snowflake(id);
-			userIndices[id] = users.Count;
-			userIndex.Add(idSnowflake);
-			
-			users[idSnowflake] = new ViewerJson.JsonUser {
 				Name = user.Name,
 				Avatar = user.AvatarUrl,
 				Tag = user.Discriminator
 			};
 		}
 
-		return (users, userIndex, userIndices);
+		return users;
 	}
 
-	private static async Task<(List<ViewerJson.JsonServer> Servers, Dictionary<ulong, int> ServerIndices)> GenerateServerList(IDatabaseFile db, HashSet<ulong> serverIds) {
+	private static async Task<Dictionary<Snowflake, ViewerJson.JsonServer>> GenerateServerList(IDatabaseFile db, HashSet<ulong> serverIds, CancellationToken cancellationToken) {
-		var servers = new List<ViewerJson.JsonServer>();
+		var servers = new Dictionary<Snowflake, ViewerJson.JsonServer>();
-		var serverIndices = new Dictionary<ulong, int>();
 
-		await foreach (var server in db.Servers.Get()) {
+		await foreach (var server in db.Servers.Get(cancellationToken)) {
-			var id = server.Id;
+			if (!serverIds.Contains(server.Id)) {
-			if (!serverIds.Contains(id)) {
 				continue;
 			}
 
-			serverIndices[id] = servers.Count;
+			servers[server.Id] = new ViewerJson.JsonServer {
-			
-			servers.Add(new ViewerJson.JsonServer {
 				Name = server.Name,
 				Type = ServerTypes.ToJsonViewerString(server.Type)
-			});
+			};
 		}
 
-		return (servers, serverIndices);
+		return servers;
 	}
 
-	private static Dictionary<Snowflake, ViewerJson.JsonChannel> GenerateChannelList(List<Channel> includedChannels, Dictionary<ulong, int> serverIndices) {
+	private static Dictionary<Snowflake, ViewerJson.JsonChannel> GenerateChannelList(List<Channel> includedChannels) {
 		var channels = new Dictionary<Snowflake, ViewerJson.JsonChannel>();
 
 		foreach (var channel in includedChannels) {
-			var channelIdSnowflake = new Snowflake(channel.Id);
+			channels[channel.Id] = new ViewerJson.JsonChannel {
-			
+				Server = channel.Server,
-			channels[channelIdSnowflake] = new ViewerJson.JsonChannel {
-				Server = serverIndices[channel.Server],
 				Name = channel.Name,
 				Parent = channel.ParentId?.ToString(),
 				Position = channel.Position,
@@ -125,51 +110,40 @@ static class ViewerJsonExport {
 		return channels;
 	}
 
-	private static Dictionary<Snowflake, Dictionary<Snowflake, ViewerJson.JsonMessage>> GenerateMessageList(List<Message> includedMessages, Dictionary<ulong, int> userIndices) {
+	private static async IAsyncEnumerable<ViewerJson.JsonMessage> GenerateMessageList(IDatabaseFile db, MessageFilter? filter, [EnumeratorCancellation] CancellationToken cancellationToken) {
-		var data = new Dictionary<Snowflake, Dictionary<Snowflake, ViewerJson.JsonMessage>>();
+		await foreach (var message in db.Messages.Get(filter, cancellationToken)) {
+			yield return new ViewerJson.JsonMessage {
+				Id = message.Id,
+				C = message.Channel,
+				U = message.Sender,
+				T = message.Timestamp,
+				M = string.IsNullOrEmpty(message.Text) ? null : message.Text,
+				Te = message.EditTimestamp,
+				R = message.RepliedToId?.ToString(),
 
-		foreach (var grouping in includedMessages.GroupBy(static message => message.Channel)) {
+				A = message.Attachments.IsEmpty ? null : message.Attachments.Select(static attachment => {
-			var channelIdSnowflake = new Snowflake(grouping.Key);
+					var a = new ViewerJson.JsonMessageAttachment {
-			var channelData = new Dictionary<Snowflake, ViewerJson.JsonMessage>();
+						Url = attachment.DownloadUrl,
+						Name = Uri.TryCreate(attachment.NormalizedUrl, UriKind.Absolute, out var uri) ? Path.GetFileName(uri.LocalPath) : attachment.NormalizedUrl
+					};
 
-			foreach (var message in grouping) {
+					if (attachment is { Width: not null, Height: not null }) {
-				var messageIdSnowflake = new Snowflake(message.Id);
+						a.Width = attachment.Width;
+						a.Height = attachment.Height;
+					}
 
-				channelData[messageIdSnowflake] = new ViewerJson.JsonMessage {
+					return a;
-					U = userIndices[message.Sender],
+				}).ToArray(),
-					T = message.Timestamp,
-					M = string.IsNullOrEmpty(message.Text) ? null : message.Text,
-					Te = message.EditTimestamp,
-					R = message.RepliedToId?.ToString(),
 
-					A = message.Attachments.IsEmpty ? null : message.Attachments.Select(static attachment => {
+				E = message.Embeds.IsEmpty ? null : message.Embeds.Select(static embed => embed.Json).ToArray(),
-						var a = new ViewerJson.JsonMessageAttachment {
-							Url = attachment.DownloadUrl,
-							Name = Uri.TryCreate(attachment.NormalizedUrl, UriKind.Absolute, out var uri) ? Path.GetFileName(uri.LocalPath) : attachment.NormalizedUrl
-						};
 
-						if (attachment is { Width: not null, Height: not null }) {
+				Re = message.Reactions.IsEmpty ? null : message.Reactions.Select(static reaction => new ViewerJson.JsonMessageReaction {
-							a.Width = attachment.Width;
+					Id = reaction.EmojiId?.ToString(),
-							a.Height = attachment.Height;
+					N = reaction.EmojiName,
-						}
+					A = reaction.EmojiFlags.HasFlag(EmojiFlags.Animated),
-
+					C = reaction.Count
-						return a;
+				}).ToArray()
-					}).ToArray(),
+			};
-					
-					E = message.Embeds.IsEmpty ? null : message.Embeds.Select(static embed => embed.Json).ToArray(),
-					
-					Re = message.Reactions.IsEmpty ? null : message.Reactions.Select(static reaction => new ViewerJson.JsonMessageReaction {
-						Id = reaction.EmojiId?.ToString(),
-						N = reaction.EmojiName,
-						A = reaction.EmojiFlags.HasFlag(EmojiFlags.Animated),
-						C = reaction.Count
-					}).ToArray()
-				};
-			}
-
-			data[channelIdSnowflake] = channelData;
 		}
-
-		return data;
 	}
 }

app/Server/Database/Export/ViewerJsonMessageContext.cs

@@ -0,0 +1,11 @@
+using System.Text.Json.Serialization;
+
+namespace DHT.Server.Database.Export;
+
+[JsonSourceGenerationOptions(
+	Converters = [typeof(SnowflakeJsonSerializer)],
+	PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase,
+	GenerationMode = JsonSourceGenerationMode.Default
+)]
+[JsonSerializable(typeof(ViewerJson.JsonMessage))]
+sealed partial class ViewerJsonMessageContext : JsonSerializerContext;

app/Server/Database/Export/ViewerJsonMetadataContext.cs

@@ -7,5 +7,5 @@ namespace DHT.Server.Database.Export;
 	PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase,
 	GenerationMode = JsonSourceGenerationMode.Default
 )]
-[JsonSerializable(typeof(ViewerJson))]
+[JsonSerializable(typeof(ViewerJson.JsonMeta))]
-sealed partial class ViewerJsonContext : JsonSerializerContext;
+sealed partial class ViewerJsonMetadataContext : JsonSerializerContext;

app/Server/Database/Repositories/IServerRepository.cs

@@ -14,7 +14,7 @@ public interface IServerRepository {
 	
 	Task<long> Count(CancellationToken cancellationToken = default);
 	
-	IAsyncEnumerable<Data.Server> Get();
+	IAsyncEnumerable<Data.Server> Get(CancellationToken cancellationToken = default);
 
 	internal sealed class Dummy : IServerRepository {
 		public IObservable<long> TotalCount { get; } = Observable.Return(0L);
@@ -27,7 +27,7 @@ public interface IServerRepository {
 			return Task.FromResult(0L);
 		}
 
-		public IAsyncEnumerable<Data.Server> Get() {
+		public IAsyncEnumerable<Data.Server> Get(CancellationToken cancellationToken) {
 			return AsyncEnumerable.Empty<Data.Server>();
 		}
 	}

app/Server/Database/Repositories/IUserRepository.cs

@@ -15,7 +15,7 @@ public interface IUserRepository {
 	
 	Task<long> Count(CancellationToken cancellationToken = default);
 	
-	IAsyncEnumerable<User> Get();
+	IAsyncEnumerable<User> Get(CancellationToken cancellationToken = default);
 
 	internal sealed class Dummy : IUserRepository {
 		public IObservable<long> TotalCount { get; } = Observable.Return(0L);
@@ -28,7 +28,7 @@ public interface IUserRepository {
 			return Task.FromResult(0L);
 		}
 
-		public IAsyncEnumerable<User> Get() {
+		public IAsyncEnumerable<User> Get(CancellationToken cancellationToken) {
 			return AsyncEnumerable.Empty<User>();
 		}
 	}

app/Server/Database/Sqlite/Repositories/SqliteServerRepository.cs

@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
 using DHT.Server.Data;
@@ -46,13 +47,13 @@ sealed class SqliteServerRepository : BaseSqliteRepository, IServerRepository {
 		return await conn.ExecuteReaderAsync("SELECT COUNT(*) FROM servers", static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 
-	public async IAsyncEnumerable<Data.Server> Get() {
+	public async IAsyncEnumerable<Data.Server> Get([EnumeratorCancellation] CancellationToken cancellationToken) {
 		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command("SELECT id, name, type FROM servers");
-		await using var reader = await cmd.ExecuteReaderAsync();
+		await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
 
-		while (await reader.ReadAsync()) {
+		while (await reader.ReadAsync(cancellationToken)) {
 			yield return new Data.Server {
 				Id = reader.GetUint64(0),
 				Name = reader.GetString(1),

app/Server/Database/Sqlite/Repositories/SqliteUserRepository.cs

@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
 using DHT.Server.Data;
@@ -58,13 +59,13 @@ sealed class SqliteUserRepository : BaseSqliteRepository, IUserRepository {
 		return await conn.ExecuteReaderAsync("SELECT COUNT(*) FROM users", static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 
-	public async IAsyncEnumerable<User> Get() {
+	public async IAsyncEnumerable<User> Get([EnumeratorCancellation] CancellationToken cancellationToken) {
 		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command("SELECT id, name, avatar_url, discriminator FROM users");
-		await using var reader = await cmd.ExecuteReaderAsync();
+		await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
 
-		while (await reader.ReadAsync()) {
+		while (await reader.ReadAsync(cancellationToken)) {
 			yield return new User {
 				Id = reader.GetUint64(0),
 				Name = reader.GetString(1),

app/Server/Endpoints/BaseEndpoint.cs

@@ -47,4 +47,13 @@ abstract class BaseEndpoint(IDatabaseFile db) {
 			throw new HttpException(HttpStatusCode.UnsupportedMediaType, "This endpoint only accepts JSON.");
 		}
 	}
+	
+	protected static Guid GetSessionId(HttpRequest request) {
+		if (request.Query.TryGetValue("session", out var sessionIdValue) && sessionIdValue.Count == 1 && Guid.TryParse(sessionIdValue[0], out Guid sessionId)) {
+			return sessionId;
+		}
+		else {
+			throw new HttpException(HttpStatusCode.BadRequest, "Invalid session ID.");
+		}
+	}
 }

app/Server/Endpoints/GetViewerDataEndpoint.cs

@@ -1,25 +0,0 @@
-using System;
-using System.Net;
-using System.Net.Mime;
-using System.Threading;
-using System.Threading.Tasks;
-using DHT.Server.Database;
-using DHT.Server.Database.Export;
-using DHT.Server.Service.Viewer;
-using DHT.Utils.Http;
-using Microsoft.AspNetCore.Http;
-
-namespace DHT.Server.Endpoints; 
-
-sealed class GetViewerDataEndpoint(IDatabaseFile db, ViewerSessions viewerSessions) : BaseEndpoint(db) {
-	protected override Task Respond(HttpRequest request, HttpResponse response, CancellationToken cancellationToken) {
-		if (!request.Query.TryGetValue("session", out var sessionIdValue) || sessionIdValue.Count != 1 || !Guid.TryParse(sessionIdValue[0], out Guid sessionId)) {
-			throw new HttpException(HttpStatusCode.BadRequest, "Invalid session ID.");
-		}
-		
-		response.ContentType = MediaTypeNames.Application.Json;
-		
-		var session = viewerSessions.Get(sessionId);
-		return ViewerJsonExport.Generate(response.Body, Db, session.MessageFilter, cancellationToken);
-	}
-}

app/Server/Endpoints/GetViewerMessagesEndpoint.cs

@@ -0,0 +1,18 @@
+using System.Threading;
+using System.Threading.Tasks;
+using DHT.Server.Database;
+using DHT.Server.Database.Export;
+using DHT.Server.Service.Viewer;
+using Microsoft.AspNetCore.Http;
+
+namespace DHT.Server.Endpoints; 
+
+sealed class GetViewerMessagesEndpoint(IDatabaseFile db, ViewerSessions viewerSessions) : BaseEndpoint(db) {
+	protected override Task Respond(HttpRequest request, HttpResponse response, CancellationToken cancellationToken) {
+		var sessionId = GetSessionId(request);
+		var session = viewerSessions.Get(sessionId);
+		
+		response.ContentType = "application/x-ndjson";
+		return ViewerJsonExport.GetMessages(response.Body, Db, session.MessageFilter, cancellationToken);
+	}
+}

app/Server/Endpoints/GetViewerMetadataEndpoint.cs

@@ -0,0 +1,19 @@
+using System.Net.Mime;
+using System.Threading;
+using System.Threading.Tasks;
+using DHT.Server.Database;
+using DHT.Server.Database.Export;
+using DHT.Server.Service.Viewer;
+using Microsoft.AspNetCore.Http;
+
+namespace DHT.Server.Endpoints; 
+
+sealed class GetViewerMetadataEndpoint(IDatabaseFile db, ViewerSessions viewerSessions) : BaseEndpoint(db) {
+	protected override Task Respond(HttpRequest request, HttpResponse response, CancellationToken cancellationToken) {
+		var sessionId = GetSessionId(request);
+		var session = viewerSessions.Get(sessionId);
+		
+		response.ContentType = MediaTypeNames.Application.Json;
+		return ViewerJsonExport.GetMetadata(response.Body, Db, session.MessageFilter, cancellationToken);
+	}
+}

app/Server/Service/ServerStartup.cs

@@ -51,7 +51,8 @@ sealed class Startup {
 		app.UseRouting();
 		app.UseEndpoints(endpoints => {
 			endpoints.MapGet("/get-tracking-script", new GetTrackingScriptEndpoint(db, parameters, resources).Handle);
-			endpoints.MapGet("/get-viewer-data", new GetViewerDataEndpoint(db, viewerSessions).Handle);
+			endpoints.MapGet("/get-viewer-metadata", new GetViewerMetadataEndpoint(db, viewerSessions).Handle);
+			endpoints.MapGet("/get-viewer-messages", new GetViewerMessagesEndpoint(db, viewerSessions).Handle);
 			endpoints.MapGet("/get-downloaded-file/{url}", new GetDownloadedFileEndpoint(db).Handle);
 			endpoints.MapPost("/track-channel", new TrackChannelEndpoint(db).Handle);
 			endpoints.MapPost("/track-users", new TrackUsersEndpoint(db).Handle);