1# Redis Recipe — C# (.NET) — REFERENCE ONLY
2 
3## ASP.NET Core Distributed Cache Setup
4 
5### NuGet Packages
6 
7```xml
8<PackageReference Include="Microsoft.Extensions.Caching.StackExchangeRedis" Version="8.0.*" />
9<PackageReference Include="Azure.Identity" Version="1.13.*" />
10```
11 
12### Program.cs (additions)
13 
14Add these lines — do NOT replace the existing file:
15 
16```csharp
17using Azure.Identity;
18using StackExchange.Redis;
19 
20var redisHost = builder.Configuration["REDIS_HOST"];
21var configOptions = ConfigurationOptions.Parse($"{redisHost}:6380");
22configOptions.Ssl = true;
23configOptions.AbortOnConnectFail = false;
24 
25// ConfigureForAzureWithTokenCredentialAsync handles automatic token renewal
26await configOptions.ConfigureForAzureWithTokenCredentialAsync(
27    new DefaultAzureCredential());
28 
29builder.Services.AddStackExchangeRedisCache(options =>
30{
31    options.ConfigurationOptions = configOptions;
32    options.InstanceName = "app:";
33});
34```
35 
36> 💡 `ConfigureForAzureWithTokenCredentialAsync` manages token acquisition and renewal automatically — no manual token refresh required.
37 
38### Usage
39 
40```csharp
41using Microsoft.Extensions.Caching.Distributed;
42 
43app.MapGet("/api/cached", async (IDistributedCache cache) =>
44{
45    var value = await cache.GetStringAsync("my-key");
46    if (value is null)
47    {
48        value = "computed-value";
49        await cache.SetStringAsync("my-key", value,
50            new DistributedCacheEntryOptions { AbsoluteExpirationRelativeToNow = TimeSpan.FromMinutes(5) });
51    }
52    return Results.Ok(new { value });
53});
54```
55 
56## Files to Modify
57 
58| File | Action |
59|------|--------|
60| `Program.cs` | Add Redis cache registration |
61| `*.csproj` | Add NuGet packages |
62