.NET Core Web API - Memory Cache Usage

Startup.cs

// Startup.cs
public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        // Add memory cache dependencies 
        services.AddMemoryCache();
        services.AddControllers();
        services.AddSwaggerGen(c =>
        {
            c.SwaggerDoc("v1", new OpenApiInfo { Title = "WebApiInMemoryCaching", Version = "v1" });
        });
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
            app.UseSwagger();
            app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "WebApiInMemoryCaching v1"));
        }
        app.UseHttpsRedirection();
        app.UseRouting();
        app.UseAuthorization();
        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });
    }
}

// WeatherForecastController.cs 
[ApiController]
[Route("[controller]")]
public class WeatherForecastController : ControllerBase
{
    private static readonly string[] Summaries = new[]
    {
        "Freezing", "Bracing", "Chilly", "Cool", "Mild",
        "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
    };

    private readonly ILogger<WeatherForecastController> _logger;
    private readonly IMemoryCache _memoryCache;
    private readonly string weatherForecastKey = "weatherForecastKey";
    
    public WeatherForecastController(ILogger<WeatherForecastController> logger, IMemoryCache memoryCache)
    {
        _logger = logger;
        _memoryCache = memoryCache;
    }

    [HttpGet]
    public IEnumerable<WeatherForecast> Get()
    {
        IEnumerable<WeatherForecast> weatherForecastCollection = null;
        
        // If found in cache, return cached data
        if (_memoryCache.TryGetValue(weatherForecastKey, out weatherForecastCollection))
        {
            return weatherForecastCollection;
        }

        // If not found, then calculate response
        weatherForecastCollection = GetWeatherForecast();
        
        // Set cache options
        var cacheOptions = new MemoryCacheEntryOptions()
            .SetSlidingExpiration(TimeSpan.FromSeconds(30));

        / Set object in cache
        _memoryCache.Set(weatherForecastKey, weatherForecastCollection, cacheOptions);
        return weatherForecastCollection;
    }

    private static IEnumerable<WeatherForecast> GetWeatherForecast()
    {
        var rng = new Random();
        return Enumerable.Range(1, 5).Select(index => new WeatherForecast
        {
            Date = DateTime.Now.AddDays(index),
            TemperatureC = rng.Next(-20, 55),
            Summary = Summaries[rng.Next(Summaries.Length)]
        })
        .ToArray();
    }
}