Switch to GrpcClientIdentificationService and abolish Redis for Idents (#12)

* add GrpcClientIdentificationService

* remove unnecessary gauges

* set to no retry policy

* initialize metrics

Co-authored-by: Stanley Dimant <root.darkarchon@outlook.com>

MareSynchronosServer/MareSynchronosServices/Identity/IdentityHandler.cs

@@ -0,0 +1,62 @@
+using System.Collections.Concurrent;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace MareSynchronosServices.Identity;
+
+internal class IdentityHandler
+{
+    private readonly ConcurrentDictionary<string, ServerIdentity> cachedIdentities = new();
+
+    internal Task<string> GetUidForCharacterIdent(string ident, string serverId)
+    {
+        var exists = cachedIdentities.Any(f => f.Value.CharacterIdent == ident && f.Value.ServerId == serverId);
+        return Task.FromResult(exists ? cachedIdentities.FirstOrDefault(f => f.Value.CharacterIdent == ident && f.Value.ServerId == serverId).Key : string.Empty);
+    }
+
+    internal Task<ServerIdentity> GetIdentForuid(string uid)
+    {
+        ServerIdentity result;
+        if (!cachedIdentities.TryGetValue(uid, out result))
+        {
+            result = new ServerIdentity();
+        }
+
+        return Task.FromResult(result);
+    }
+
+    internal void SetIdent(string uid, string serverId, string ident)
+    {
+        cachedIdentities[uid] = new ServerIdentity() { ServerId = serverId, CharacterIdent = ident };
+    }
+
+    internal void RemoveIdent(string uid, string serverId)
+    {
+        if (cachedIdentities.ContainsKey(uid) && cachedIdentities[uid].ServerId == serverId)
+        {
+            cachedIdentities.TryRemove(uid, out _);
+        }
+    }
+
+    internal int GetOnlineUsers(string serverId)
+    {
+        if (string.IsNullOrEmpty(serverId))
+            return cachedIdentities.Count;
+        return cachedIdentities.Count(c => c.Value.ServerId == serverId);
+    }
+
+    internal void ClearIdentsForServer(string serverId)
+    {
+        var serverIdentities = cachedIdentities.Where(i => i.Value.ServerId == serverId);
+        foreach (var identity in serverIdentities)
+        {
+            cachedIdentities.TryRemove(identity.Key, out _);
+        }
+    }
+}
+
+internal record ServerIdentity
+{
+    public string ServerId { get; set; } = string.Empty;
+    public string CharacterIdent { get; set; } = string.Empty;
+}