From 7e89c0e4c40917a8963cc180588f644c5fca27ff Mon Sep 17 00:00:00 2001
From: Laura Hausmann <laura@hausmann.dev>
Date: Sat, 23 Mar 2024 19:02:12 +0100
Subject: [PATCH] [backend/core] Use upsert for cache store instead of
 detecting conflicts (ISH-212)

---
 .../Core/Services/CacheService.cs             | 25 ++++++++-----------
 Iceshrimp.Backend/Iceshrimp.Backend.csproj    |  1 +
 2 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/Iceshrimp.Backend/Core/Services/CacheService.cs b/Iceshrimp.Backend/Core/Services/CacheService.cs
index 3dec1e8f..138d1b06 100644
--- a/Iceshrimp.Backend/Core/Services/CacheService.cs
+++ b/Iceshrimp.Backend/Core/Services/CacheService.cs
@@ -147,21 +147,16 @@ public class CacheService([FromKeyedServices("cache")] DatabaseContext db)
 				Expiry = expiry,
 				Ttl    = ttl
 			};
-			db.Add(entity);
-			try
-			{
-				await db.SaveChangesAsync();
-			}
-			catch (UniqueConstraintException)
-			{
-				db.Remove(entity);
-				entity = await db.CacheStore.FirstOrDefaultAsync(p => p.Key == key) ??
-				         throw new Exception("Failed to fetch entity after UniqueConstraintException");
-				entity.Value  = value;
-				entity.Expiry = expiry;
-				entity.Ttl    = ttl;
-				await db.SaveChangesAsync();
-			}
+
+			await db.CacheStore.Upsert(entity)
+			        .On(p => p.Key)
+			        .WhenMatched((_, orig) => new CacheEntry
+			        {
+				        Value  = orig.Value,
+				        Expiry = orig.Expiry,
+				        Ttl    = orig.Ttl
+			        })
+			        .RunAsync();
 		}
 	}
 
diff --git a/Iceshrimp.Backend/Iceshrimp.Backend.csproj b/Iceshrimp.Backend/Iceshrimp.Backend.csproj
index 6c84bf8e..60b77ef3 100644
--- a/Iceshrimp.Backend/Iceshrimp.Backend.csproj
+++ b/Iceshrimp.Backend/Iceshrimp.Backend.csproj
@@ -25,6 +25,7 @@
         <PackageReference Include="dotNetRdf.Core" Version="3.2.6-iceshrimp"/>
         <PackageReference Include="EntityFrameworkCore.Exceptions.PostgreSQL" Version="8.0.0"/>
         <PackageReference Include="EntityFrameworkCore.Projectables" Version="3.0.4"/>
+        <PackageReference Include="FlexLabs.EntityFrameworkCore.Upsert" Version="8.0.0" />
         <PackageReference Include="Isopoh.Cryptography.Argon2" Version="2.0.0"/>
         <PackageReference Include="libsodium" Version="1.0.18.4"/>
         <PackageReference Include="Microsoft.AspNetCore.DataProtection.EntityFrameworkCore" Version="8.0.1"/>