BirthdayBot/BackgroundServices/StaleDataCleaner.cs
Noi 608ab37aec Update background services to remove guild cache references
Possibly optimized StaleDataCleaner as well by making certain database
updates asynchronous
2020-07-18 00:01:14 -07:00

86 lines
3.6 KiB
C#

using BirthdayBot.Data;
using NpgsqlTypes;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace BirthdayBot.BackgroundServices
{
/// <summary>
/// Automatically removes database information for guilds that have not been accessed in a long time.
/// </summary>
class StaleDataCleaner : BackgroundService
{
public StaleDataCleaner(BirthdayBot instance) : base(instance) { }
public override async Task OnTick()
{
// Build a list of all values to update
var updateList = new Dictionary<ulong, List<ulong>>();
foreach (var g in BotInstance.DiscordClient.Guilds)
{
var existingUsers = new List<ulong>();
updateList[g.Id] = existingUsers;
// Get list of IDs for all users who exist in the database and currently exist in the guild
var savedUserIds = from cu in await GuildUserConfiguration.LoadAllAsync(g.Id) select cu.UserId;
var guildUserIds = from gu in g.Users select gu.Id;
var existingCachedIds = savedUserIds.Intersect(guildUserIds);
}
using var db = await Database.OpenConnectionAsync();
// Statement for updating last_seen in guilds
var cUpdateGuild = db.CreateCommand();
cUpdateGuild.CommandText = $"update {GuildConfiguration.BackingTable} set last_seen = now() "
+ "where guild_id = @Gid";
var pUpdateG = cUpdateGuild.Parameters.Add("@Gid", NpgsqlDbType.Bigint);
cUpdateGuild.Prepare();
// Statement for updating last_seen in guild users
var cUpdateGuildUser = db.CreateCommand();
cUpdateGuildUser.CommandText = $"update {GuildUserConfiguration.BackingTable} set last_seen = now() "
+ "where guild_id = @Gid and user_id = @Uid";
var pUpdateGU_g = cUpdateGuildUser.Parameters.Add("@Gid", NpgsqlDbType.Bigint);
var pUpdateGU_u = cUpdateGuildUser.Parameters.Add("@Uid", NpgsqlDbType.Bigint);
cUpdateGuildUser.Prepare();
// Do actual updates
var updates = new List<Task>();
foreach (var item in updateList)
{
var guild = item.Key;
var userlist = item.Value;
pUpdateG.Value = (long)guild;
updates.Add(cUpdateGuild.ExecuteNonQueryAsync());
pUpdateGU_g.Value = (long)guild;
foreach (var userid in userlist)
{
pUpdateGU_u.Value = (long)userid;
updates.Add(cUpdateGuildUser.ExecuteNonQueryAsync());
}
}
await Task.WhenAll(updates);
// Delete all old values - expects referencing tables to have 'on delete cascade'
using var t = db.BeginTransaction();
int staleGuilds, staleUsers;
using (var c = db.CreateCommand())
{
// Delete data for guilds not seen in 4 weeks
c.CommandText = $"delete from {GuildConfiguration.BackingTable} where (now() - interval '28 days') > last_seen";
staleGuilds = c.ExecuteNonQuery();
}
using (var c = db.CreateCommand())
{
// Delete data for users not seen in 8 weeks
c.CommandText = $"delete from {GuildUserConfiguration.BackingTable} where (now() - interval '56 days') > last_seen";
staleUsers = c.ExecuteNonQuery();
}
Log($"Will remove {staleGuilds} guilds, {staleUsers} users.");
t.Commit();
}
}
}