fix: use FirstOrDefault instead of Single when reading the identity

Author: tnotheis

Modules/Devices/src/Devices.Application/Identities/Queries/IsIdentityOfUserDeleted/Handler.cs

@@ -16,17 +16,29 @@ public Handler(IIdentitiesRepository identitiesRepository)
 
     public async Task<IsIdentityOfUserDeletedResponse> Handle(IsIdentityOfUserDeletedQuery request, CancellationToken cancellationToken)
     {
-        var identity = await _identitiesRepository.FindSingle(Identity.HasUser(request.Username), cancellationToken);
+        var identity = await _identitiesRepository.FindFirst(Identity.HasUser(request.Username), cancellationToken);
 
-        if (identity.IsGracePeriodOver)
-            return new IsIdentityOfUserDeletedResponse(true, identity.DeletionGracePeriodEndsAt);
+        bool isDeleted;
+        DateTime? deletionGracePeriodEndsAt;
 
-        var auditLogEntries = await _identitiesRepository.GetIdentityDeletionProcessAuditLogs(
-            IdentityDeletionProcessAuditLogEntry.IsAssociatedToUser(Username.Parse(request.Username)),
-            cancellationToken);
+        if (identity != null)
+        {
+            isDeleted = identity.IsGracePeriodOver;
+            deletionGracePeriodEndsAt = identity.IsGracePeriodOver ? identity.DeletionGracePeriodEndsAt : null;
+        }
+        else
+        {
+            var auditLogEntries = await _identitiesRepository.GetIdentityDeletionProcessAuditLogs(
+                IdentityDeletionProcessAuditLogEntry.IsAssociatedToUser(Username.Parse(request.Username)),
+                cancellationToken);
 
-        var deletionCompletedAuditLogEntry = auditLogEntries.FirstOrDefault(l => l.MessageKey == MessageKey.DeletionCompleted);
+            var deletionCompletedAuditLogEntry = auditLogEntries.FirstOrDefault(l => l.MessageKey == MessageKey.DeletionCompleted);
+
+            isDeleted = deletionCompletedAuditLogEntry != null;
+            deletionGracePeriodEndsAt = deletionCompletedAuditLogEntry?.CreatedAt;
+        }
+
+        return new IsIdentityOfUserDeletedResponse(isDeleted, deletionGracePeriodEndsAt);
 
-        return new IsIdentityOfUserDeletedResponse(deletionCompletedAuditLogEntry != null, deletionCompletedAuditLogEntry?.CreatedAt);
     }
 }

Modules/Devices/src/Devices.Application/Infrastructure/Persistence/Repository/IIdentitiesRepository.cs

@@ -16,7 +16,7 @@ public interface IIdentitiesRepository
     Task<IEnumerable<Identity>> FindAllWithDeletionProcessInStatus(DeletionProcessStatus status, CancellationToken cancellationToken, bool track = false);
     Task<int> CountByClientId(string clientId, CancellationToken cancellationToken);
     Task<IEnumerable<Identity>> Find(Expression<Func<Identity, bool>> filter, CancellationToken cancellationToken, bool track = false);
-    Task<Identity> FindSingle(Expression<Func<Identity, bool>> filter, CancellationToken cancellationToken, bool track = false);
+    Task<Identity?> FindFirst(Expression<Func<Identity, bool>> filter, CancellationToken cancellationToken, bool track = false);
     Task Delete(Expression<Func<Identity, bool>> filter, CancellationToken cancellationToken);
 
     Task Add(Identity identity, string password);

Modules/Devices/src/Devices.Infrastructure/Persistence/Repository/IdentitiesRepository.cs

@@ -171,12 +171,12 @@ public async Task<IEnumerable<Identity>> Find(Expression<Func<Identity, bool>> f
             .ToListAsync(cancellationToken);
     }
 
-    public async Task<Identity> FindSingle(Expression<Func<Identity, bool>> filter, CancellationToken cancellationToken, bool track = false)
+    public async Task<Identity?> FindFirst(Expression<Func<Identity, bool>> filter, CancellationToken cancellationToken, bool track = false)
     {
         return await (track ? _identities : _readonlyIdentities)
             .IncludeAll(_dbContext)
             .Where(filter)
-            .SingleAsync(cancellationToken);
+            .FirstOrDefaultAsync(cancellationToken);
     }
 
     public async Task Delete(Expression<Func<Identity, bool>> filter, CancellationToken cancellationToken)