private PolicyRegistry BuildPolicyRegistry()
{
var circuitBreakerPolicy = Policy.Handle <HttpRequestException>()
.CircuitBreakerAsync(1, TimeSpan.FromMinutes(1));
var memoryCache = new MemoryCache(new MemoryCacheOptions());
var memoryCacheProvider = new Polly.Caching.MemoryCache.MemoryCacheProvider(memoryCache);
var cachePolicy = Policy.CacheAsync(memoryCacheProvider, TimeSpan.FromSeconds(30));
var cacheAndCircuitBreakerPolicy = cachePolicy.WrapAsync(Policy.Handle <HttpRequestException>()
.CircuitBreakerAsync(1, TimeSpan.FromMinutes(1)));
var fallbackCacheAndBreaker = Policy <Promotion>
.Handle <BrokenCircuitException>()
.Or <HttpRequestException>()
.FallbackAsync <Promotion>(new Promotion()
{
Title = "Some Fallback Promotion",
Description = "The Promotion API is down so we're showing something else",
GeneratedTimestamp = DateTime.UtcNow
}
)
.WrapAsync(cacheAndCircuitBreakerPolicy);
var registry = new PolicyRegistry();
registry.Add("PromoFallback", fallbackCacheAndBreaker);
registry.Add("Promo", cacheAndCircuitBreakerPolicy);
registry.Add("Merchant", circuitBreakerPolicy);
return(registry);
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env, IMemoryCache memoryCache)
{
Polly.Caching.IAsyncCacheProvider memoryCacheProvider
= new Polly.Caching.MemoryCache.MemoryCacheProvider(memoryCache);
CachePolicy <HttpResponseMessage> cachePolicy =
Policy.CacheAsync <HttpResponseMessage>(memoryCacheProvider, TimeSpan.FromMinutes(5));
_myRegistry.Add("myLocalCachePolicy", cachePolicy);
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseMvc();
}
/// <summary>
/// 缓存
/// </summary>
private static void Caching()
{
//Install-Package Microsoft.Extensions.Caching.Memory
Microsoft.Extensions.Caching.Memory.IMemoryCache memoryCache = new Microsoft.Extensions.Caching.Memory.MemoryCache(new Microsoft.Extensions.Caching.Memory.MemoryCacheOptions());
//Install-Package Polly.Caching.MemoryCache
Polly.Caching.MemoryCache.MemoryCacheProvider memoryCacheProvider = new Polly.Caching.MemoryCache.MemoryCacheProvider(memoryCache);
CachePolicy policy = Policy.Cache(memoryCacheProvider, TimeSpan.FromSeconds(5));
Random rand = new Random();
while (true)
{
int i = rand.Next(5);
Console.WriteLine("产生" + i);
var context = new Context("doublecache" + i);
int result = policy.Execute(ctx =>
{
Console.WriteLine("Execute计算" + i);
return(i * 2);
}, context);
Console.WriteLine("计算结果：" + result);
Thread.Sleep(500);
}
}