What is Redis Cache?

Redis is an open source (BSD licensed), in-memory data structure store that can be used as a database, cache, message broker, and streaming engine.

Why Redis?

All Redis data resides in memory, which enables low latency and high throughput data access. Unlike traditional databases, In-memory data stores don’t require a trip to disk, reducing engine latency to microseconds. Because of this, in-memory data stores can support an order of magnitude more operations and faster response times.
Easy to use.
High availability and scalability.
Open Source.
Flexible data structures.

Step 1

You need to configure your Redis server. For that you can download and run an image of Redis in a docker container.

Step 2

Once your Redis server is up and running you need to install the following nuget package

Microsoft.Extensions.Caching.StackExchangeRedis

Step 3

On the ConnectionStrings section of the appsettings.json file, add the following entry

 "ConnectionStrings": {
    "Redis" : "localhost:6379"
  },

Step 4

Then you need to configure your connection to the Redis server in the Program.cs file

builder.Services.AddStackExchangeRedisCache(redisOptions =>
{
    string connection = builder.Configuration.GetConnectionString("Redis");
    redisOptions.Configuration = connection;
});

Step 5

On your controller, you'll need to inject IDistributedCachevia Dependency Injection.

        private readonly IDistributedCache? _cache;

        public TvShowsController(TvShowContext context, IDistributedCache cache)
        {
            _context = context;
            _cache = cache;
        }

Step 6

Finally is time to store and retrieve values to and from your Redis Cache.

[HttpGet]
        public ActionResult<IEnumerable<TvShow>> GetTvShows()
        {
            string cachedData = _cache.GetString("cachedData");
            if (string.IsNullOrEmpty(cachedData))
            {
                var tvShows = _context.TvShows.ToList();
                string serializedObject = JsonConvert.SerializeObject(tvShows);
                _cache.SetString("cachedData", serializedObject, new DistributedCacheEntryOptions() { AbsoluteExpirationRelativeToNow = TimeSpan.FromMinutes(10) });
                return tvShows;
            }

            return JsonConvert.DeserializeObject<List<TvShow>>(cachedData);
        }

I hope you liked it, stay tuned for more!

Redis Cache in .NET