BirthdayBot/ShardInstance.cs
Noi a0571ce3d7 Add some leeway regarding incomplete user cache
Implemented several workarounds to what appearto be a library bug in
which not all users will be downloaded onto the cache. User cache
checking and downloading is delegated to a new Common method and a
new BackgroundService, respectively.
This is hopefully temporary.
2021-02-01 22:48:20 -08:00

209 lines
8.6 KiB
C#

using BirthdayBot.BackgroundServices;
using BirthdayBot.Data;
using Discord;
using Discord.Net;
using Discord.WebSocket;
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using static BirthdayBot.UserInterface.CommandsCommon;
namespace BirthdayBot
{
/// <summary>
/// Single shard instance for Birthday Bot. This shard independently handles all input and output to Discord.
/// </summary>
class ShardInstance : IDisposable
{
private readonly ShardManager _manager;
private readonly ShardBackgroundWorker _background;
private readonly Dictionary<string, CommandHandler> _dispatchCommands;
public DiscordSocketClient DiscordClient { get; }
public int ShardId => DiscordClient.ShardId;
/// <summary>
/// Returns a value showing the time in which the last background run successfully completed.
/// </summary>
public DateTimeOffset LastBackgroundRun => _background.LastBackgroundRun;
public Configuration Config => _manager.Config;
/// <summary>
/// Returns this shard's connection score.
/// See <see cref="BackgroundServices.ConnectionStatus"/> for details on what this means.
/// </summary>
public int ConnectionScore => _background.ConnectionScore;
/// <summary>
/// Prepares and configures the shard instances, but does not yet start its connection.
/// </summary>
public ShardInstance(ShardManager manager, DiscordSocketClient client, Dictionary<string, CommandHandler> commands)
{
_manager = manager;
_dispatchCommands = commands;
DiscordClient = client;
DiscordClient.Log += Client_Log;
DiscordClient.Ready += Client_Ready;
DiscordClient.MessageReceived += Client_MessageReceived;
// Background task constructor begins background processing immediately.
_background = new ShardBackgroundWorker(this);
DiscordClient.Disconnected += Client_Disconnected;
}
/// <summary>
/// Starts up this shard's connection to Discord and background task handling associated with it.
/// </summary>
public async Task StartAsync()
{
await DiscordClient.LoginAsync(TokenType.Bot, Config.BotToken).ConfigureAwait(false);
await DiscordClient.StartAsync().ConfigureAwait(false);
}
/// <summary>
/// Does all necessary steps to stop this shard. This method may block for a few seconds as it waits
/// for the process to finish, but will force its disposal after at most 30 seconds.
/// </summary>
public void Dispose()
{
Log("Instance", "Cleaning up...");
// Unsubscribe from own events
DiscordClient.Log -= Client_Log;
DiscordClient.Ready -= Client_Ready;
DiscordClient.MessageReceived -= Client_MessageReceived;
DiscordClient.Disconnected -= Client_Disconnected;
_background.Dispose();
try
{
if (!DiscordClient.LogoutAsync().Wait(15000))
Log("Instance", "Warning: Client has not yet logged out. Continuing cleanup.");
}
catch (Exception ex)
{
Log("Instance", "Warning: Client threw an exception when logging out: " + ex.Message);
}
try
{
if (!DiscordClient.StopAsync().Wait(5000))
Log("Instance", "Warning: Client has not yet stopped. Continuing cleanup.");
}
catch (Exception ex)
{
Log("Instance", "Warning: Client threw an exception when stopping: " + ex.Message);
}
var clientDispose = Task.Run(DiscordClient.Dispose);
if (!clientDispose.Wait(10000))
Log("Instance", "Warning: Client hanging on dispose.");
Log("Instance", "Shard instance disposed.");
}
public void Log(string source, string message) => Program.Log($"Shard {ShardId:00}] [{source}", message);
/// <summary>
/// Direct access to invoke the background task of updating birthdays in a guild, for use by the testing command.
/// </summary>
public Task<string> ForceBirthdayUpdateAsync(SocketGuild guild)
=> _background.BirthdayUpdater.SingleProcessGuildAsync(guild);
public void RequestDownloadUsers(ulong guildId) => _background.UserDownloader.RequestDownload(guildId);
#region Event handling
private Task Client_Log(LogMessage arg)
{
// Suppress certain messages
if (arg.Message != null)
{
if (arg.Message.StartsWith("Unknown Dispatch ")) return Task.CompletedTask;
switch (arg.Message) // Connection status messages replaced by ShardManager's output
{
case "Connecting":
case "Connected":
case "Ready":
case "Failed to resume previous session":
case "Resumed previous session":
case "Disconnecting":
case "Disconnected":
case "WebSocket connection was closed":
return Task.CompletedTask;
}
if (arg.Message == "Heartbeat Errored")
{
// Replace this with a custom message; do not show stack trace
Log("Discord.Net", $"{arg.Severity}: {arg.Message} - {arg.Exception.Message}");
return Task.CompletedTask;
}
Log("Discord.Net", $"{arg.Severity}: {arg.Message}");
}
if (arg.Exception != null) Log("Discord.Net", arg.Exception.ToString());
return Task.CompletedTask;
}
/// <summary>
/// Sets the shard's status to display the help command.
/// </summary>
private async Task Client_Ready() => await DiscordClient.SetGameAsync(CommandPrefix + "help");
/// <summary>
/// Notify ConnectionStatus of a disconnect.
/// </summary>
private Task Client_Disconnected(Exception arg)
{
_background.ConnStatus.Disconnected();
return Task.CompletedTask;
}
/// <summary>
/// Determines if the incoming message is an incoming command, and dispatches to the appropriate handler if necessary.
/// </summary>
private async Task Client_MessageReceived(SocketMessage msg)
{
if (!(msg.Channel is SocketTextChannel channel)) return;
if (msg.Author.IsBot || msg.Author.IsWebhook) return;
if (((IMessage)msg).Type != MessageType.Default) return;
var author = (SocketGuildUser)msg.Author;
// Limit 3:
// For all cases: base command, 2 parameters.
// Except this case: "bb.config", subcommand name, subcommand parameters in a single string
var csplit = msg.Content.Split(" ", 3, StringSplitOptions.RemoveEmptyEntries);
if (csplit.Length > 0 && csplit[0].StartsWith(CommandPrefix, StringComparison.OrdinalIgnoreCase))
{
// Determine if it's something we're listening for.
if (!_dispatchCommands.TryGetValue(csplit[0].Substring(CommandPrefix.Length), out CommandHandler command)) return;
// Load guild information here
var gconf = await GuildConfiguration.LoadAsync(channel.Guild.Id, false);
// Ban check
if (!gconf.IsBotModerator(author)) // skip check if user is a moderator
{
if (await gconf.IsUserBlockedAsync(author.Id)) return; // silently ignore
}
// Execute the command
try
{
Log("Command", $"{channel.Guild.Name}/{author.Username}#{author.Discriminator}: {msg.Content}");
await command(this, gconf, csplit, channel, author);
}
catch (Exception ex)
{
if (ex is HttpException) return;
Log("Command", ex.ToString());
try
{
channel.SendMessageAsync(":x: An unknown error occurred. It has been reported to the bot owner.").Wait();
// TODO webhook report
}
catch (HttpException) { } // Fail silently
}
}
}
#endregion
}
}