Adding Flags API

src/api/MicCheck.Api/Identities/IdentityResolutionService.cs

@@ -0,0 +1,58 @@
+using MicCheck.Api.Data;
+using Microsoft.EntityFrameworkCore;
+
+namespace MicCheck.Api.Identities;
+
+public class IdentityResolutionService(MicCheckDbContext db)
+{
+    public async Task<Identity> ResolveAsync(
+        int environmentId,
+        string identifier,
+        IReadOnlyList<TraitInput>? traits,
+        CancellationToken ct = default)
+    {
+        var identity = await db.Identities
+            .Include(i => i.Traits)
+            .FirstOrDefaultAsync(i => i.EnvironmentId == environmentId && i.Identifier == identifier, ct);
+
+        if (identity is null)
+        {
+            identity = new Identity
+            {
+                Identifier = identifier,
+                EnvironmentId = environmentId,
+                CreatedAt = DateTimeOffset.UtcNow
+            };
+            db.Identities.Add(identity);
+            await db.SaveChangesAsync(ct);
+        }
+
+        if (traits is { Count: > 0 })
+        {
+            foreach (var traitInput in traits)
+            {
+                var existing = identity.Traits.FirstOrDefault(t => t.Key == traitInput.TraitKey);
+                if (existing is not null)
+                {
+                    existing.Value = traitInput.GetStringValue();
+                    existing.ValueType = traitInput.GetValueType();
+                }
+                else
+                {
+                    var newTrait = new IdentityTrait
+                    {
+                        IdentityId = identity.Id,
+                        Key = traitInput.TraitKey,
+                        Value = traitInput.GetStringValue(),
+                        ValueType = traitInput.GetValueType()
+                    };
+                    db.IdentityTraits.Add(newTrait);
+                    identity.Traits.Add(newTrait);
+                }
+            }
+            await db.SaveChangesAsync(ct);
+        }
+
+        return identity;
+    }
+}