Store stard status in the database

PluralKit.Core/Database/Repository/ModelRepository.Shards.cs

@@ -0,0 +1,30 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+using Dapper;
+
+using NodaTime;
+
+namespace PluralKit.Core
+{
+    public partial class ModelRepository
+    {
+        public Task<IEnumerable<PKShardInfo>> GetShards(IPKConnection conn) =>
+            conn.QueryAsync<PKShardInfo>("select * from shards");
+
+        public Task SetShardStatus(IPKConnection conn, int shard, PKShardInfo.ShardStatus status) =>
+            conn.ExecuteAsync(
+                "insert into shards (id, status) values (@Id, @Status) on conflict (id) do update set status = @Status",
+                new {Id = shard, Status = status});
+
+        public Task RegisterShardHeartbeat(IPKConnection conn, int shard, Duration ping) =>
+            conn.ExecuteAsync(
+                "insert into shards (id, last_heartbeat, ping) values (@Id, now(), @Ping) on conflict (id) do update set last_heartbeat = now(), ping = @Ping",
+                new {Id = shard, Ping = ping.TotalSeconds});
+
+        public Task RegisterShardConnection(IPKConnection conn, int shard) =>
+            conn.ExecuteAsync(
+                "insert into shards (id, last_connection) values (@Id, now()) on conflict (id) do update set last_connection = now()",
+                new {Id = shard});
+    }
+}