Merge pull request #2 from ThreeMammals/feature/moveing-polly-code-fr…

…om-ocelot

Feature/moveing polly code from ocelot

Ocelot.Provider.Polly.sln

@@ -1,4 +1,5 @@
-Microsoft Visual Studio Solution File, Format Version 12.00
+
+Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 15
 VisualStudioVersion = 15.0.27130.2036
 MinimumVisualStudioVersion = 10.0.40219.1

README.md

@@ -1,10 +1,9 @@
 [<img src="http://threemammals.com/images/ocelot_logo.png">](http://threemammals.com/ocelot)
 
-[![Build status](https://ci.appveyor.com/api/projects/status/8ry4ailt7rr5mbu7?svg=true)](https://ci.appveyor.com/project/TomPallister/ocelot-cache-cachemanager)
-Windows (AppVeyor)
-[![Build Status](https://travis-ci.org/ThreeMammals/Ocelot.Provider.Polly.svg?branch=master)](https://travis-ci.org/ThreeMammals/Ocelot.Provider.Polly) Linux & OSX (Travis)
+[![Build status](https://ci.appveyor.com/api/projects/status/64dld693t29wgikc?svg=true)](https://ci.appveyor.com/project/TomPallister/ocelot-provider-polly) Windows (AppVeyor)
+[![Build Status](https://travis-ci.org/ThreeMammals/Ocelot.Provider.Polly.svg?branch=develop)](https://travis-ci.org/ThreeMammals/Ocelot.Provider.Polly) Linux & OSX (Travis)
 
-[![Coverage Status](https://coveralls.io/repos/github/ThreeMammals/Ocelot.Provider.Polly/badge.svg?branch=develop)](https://coveralls.io/github/ThreeMammals/Ocelot.Provider.Polly?branch=develop)
+[![Coverage Status](https://coveralls.io/repos/github/ThreeMammals/Ocelot.Provider.Polly/badge.svg)](https://coveralls.io/github/ThreeMammals/Ocelot.Provider.Polly)
 
 # Ocelot
 

src/Ocelot.Provider.Polly/CircuitBreaker.cs

@@ -0,0 +1,17 @@
+using Polly.CircuitBreaker;
+using Polly.Timeout;
+
+namespace Ocelot.Provider.Polly
+{
+    public class CircuitBreaker
+    {
+        public CircuitBreaker(CircuitBreakerPolicy circuitBreakerPolicy, TimeoutPolicy timeoutPolicy)
+        {
+            CircuitBreakerPolicy = circuitBreakerPolicy;
+            TimeoutPolicy = timeoutPolicy;
+        }
+
+        public CircuitBreakerPolicy CircuitBreakerPolicy { get; private set; }
+        public TimeoutPolicy TimeoutPolicy { get; private set; }
+    }
+}

src/Ocelot.Provider.Polly/Ocelot.Provider.Polly.csproj

@@ -4,7 +4,7 @@
     <RuntimeFrameworkVersion>2.0.0</RuntimeFrameworkVersion>
     <NETStandardImplicitPackageVersion>2.0.0</NETStandardImplicitPackageVersion>
     <NoPackageAnalysis>true</NoPackageAnalysis>
-    <Description>Provides Ocelot extensions to use CacheManager.Net</Description>
+    <Description>Provides Ocelot extensions to use Polly.NET</Description>
     <AssemblyTitle>Ocelot.Provider.Polly</AssemblyTitle>
     <VersionPrefix>0.0.0-dev</VersionPrefix>
     <AssemblyName>Ocelot.Provider.Polly</AssemblyName>
@@ -26,9 +26,10 @@
     <DebugSymbols>True</DebugSymbols>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Ocelot" Version="10.0.2" />
+    <PackageReference Include="Ocelot" Version="10.0.3" />
     <PackageReference Include="StyleCop.Analyzers" Version="1.0.2">
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
+    <PackageReference Include="Polly" Version="6.0.1" />
   </ItemGroup>
 </Project>

src/Ocelot.Provider.Polly/OcelotBuilderExtensions.cs

@@ -1,11 +1,37 @@
 namespace Ocelot.Provider.Polly
 {
+    using System;
+    using System.Collections.Generic;
+    using System.Net.Http;
+    using System.Threading.Tasks;
+    using Configuration;
     using DependencyInjection;
+    using Errors;
+    using global::Polly.CircuitBreaker;
+    using global::Polly.Timeout;
+    using Logging;
+    using Microsoft.Extensions.DependencyInjection;
+    using Requester;
 
     public static class OcelotBuilderExtensions
     {
-        public static IOcelotBuilder AddSomething(this IOcelotBuilder builder)
+        public static IOcelotBuilder AddPolly(this IOcelotBuilder builder)
         {
+            var errorMapping = new Dictionary<Type, Func<Exception, Error>>
+            {
+                {typeof(TaskCanceledException), e => new RequestTimedOutError(e)},
+                {typeof(TimeoutRejectedException), e => new RequestTimedOutError(e)},
+                {typeof(BrokenCircuitException), e => new RequestTimedOutError(e)}
+            };
+
+            builder.Services.AddSingleton(errorMapping);
+
+            DelegatingHandler QosDelegatingHandlerDelegate(DownstreamReRoute reRoute, IOcelotLoggerFactory logger)
+            {
+                return new PollyCircuitBreakingDelegatingHandler(new PollyQoSProvider(reRoute, logger), logger);
+            }
+
+            builder.Services.AddSingleton((QosDelegatingHandlerDelegate) QosDelegatingHandlerDelegate);
             return builder;
         }
     }

src/Ocelot.Provider.Polly/PollyCircuitBreakingDelegatingHandler.cs

@@ -0,0 +1,43 @@
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Ocelot.Logging;
+using Polly;
+using Polly.CircuitBreaker;
+
+namespace Ocelot.Provider.Polly
+{
+    public class PollyCircuitBreakingDelegatingHandler : DelegatingHandler
+    {
+        private readonly PollyQoSProvider _qoSProvider;
+        private readonly IOcelotLogger _logger;
+
+        public PollyCircuitBreakingDelegatingHandler(
+            PollyQoSProvider qoSProvider,
+            IOcelotLoggerFactory loggerFactory)
+        {
+            _qoSProvider = qoSProvider;
+            _logger = loggerFactory.CreateLogger<PollyCircuitBreakingDelegatingHandler>();
+        }
+
+        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            try
+            {
+                return await Policy
+                    .WrapAsync(_qoSProvider.CircuitBreaker.CircuitBreakerPolicy, _qoSProvider.CircuitBreaker.TimeoutPolicy)
+                    .ExecuteAsync(() => base.SendAsync(request,cancellationToken));
+            }
+            catch (BrokenCircuitException ex)
+            {
+                _logger.LogError($"Reached to allowed number of exceptions. Circuit is open",ex);
+                throw;
+            }
+            catch (HttpRequestException ex)
+            {
+                _logger.LogError($"Error in CircuitBreakingDelegatingHandler.SendAync", ex);
+                throw;
+            }
+        }
+    }
+}

src/Ocelot.Provider.Polly/PollyQoSProvider.cs

@@ -0,0 +1,52 @@
+namespace Ocelot.Provider.Polly
+{
+    using System;
+    using System.Net.Http;
+    using global::Polly;
+    using global::Polly.CircuitBreaker;
+    using global::Polly.Timeout;
+    using Ocelot.Configuration;
+    using Ocelot.Logging;
+
+    public class PollyQoSProvider
+    {
+        private readonly CircuitBreakerPolicy _circuitBreakerPolicy;
+        private readonly TimeoutPolicy _timeoutPolicy;
+        private readonly IOcelotLogger _logger;
+
+        public PollyQoSProvider(DownstreamReRoute reRoute, IOcelotLoggerFactory loggerFactory)
+        {
+            _logger = loggerFactory.CreateLogger<PollyQoSProvider>();
+
+            Enum.TryParse(reRoute.QosOptions.TimeoutStrategy, out TimeoutStrategy strategy);
+
+            _timeoutPolicy = Policy.TimeoutAsync(TimeSpan.FromMilliseconds(reRoute.QosOptions.TimeoutValue), strategy);
+
+            _circuitBreakerPolicy = Policy
+                .Handle<HttpRequestException>()
+                .Or<TimeoutRejectedException>()
+                .Or<TimeoutException>()
+                .CircuitBreakerAsync(
+                    exceptionsAllowedBeforeBreaking: reRoute.QosOptions.ExceptionsAllowedBeforeBreaking,
+                    durationOfBreak: TimeSpan.FromMilliseconds(reRoute.QosOptions.DurationOfBreak),
+                    onBreak: (ex, breakDelay) =>
+                    {
+                        _logger.LogError(
+                            ".Breaker logging: Breaking the circuit for " + breakDelay.TotalMilliseconds + "ms!", ex);
+                    },
+                    onReset: () =>
+                    {
+                        _logger.LogDebug(".Breaker logging: Call ok! Closed the circuit again.");
+                    },
+                    onHalfOpen: () =>
+                    {
+                        _logger.LogDebug(".Breaker logging: Half-open; next call is a trial.");
+                    }
+                );
+
+            CircuitBreaker = new CircuitBreaker(_circuitBreakerPolicy, _timeoutPolicy);
+        }
+
+        public CircuitBreaker CircuitBreaker { get; }
+    }
+}

src/Ocelot.Provider.Polly/RequestTimedOutError.cs

@@ -0,0 +1,13 @@
+namespace Ocelot.Provider.Polly
+{
+    using System;
+    using Errors;
+
+    public class RequestTimedOutError : Error
+    {
+        public RequestTimedOutError(Exception exception)
+            : base($"Timeout making http request, exception: {exception}", OcelotErrorCode.RequestTimedOutError)
+        {
+        }
+    }
+}

test/Ocelot.Provider.Polly.AcceptanceTests/Ocelot.Provider.Polly.AcceptanceTests.csproj

@@ -33,7 +33,7 @@
     <PackageReference Include="Microsoft.AspNetCore.All" Version="2.1.1" />
     <PackageReference Include="Microsoft.AspNetCore.TestHost" Version="2.1.1" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.7.2" />
-    <PackageReference Include="Ocelot" Version="10.0.2" />
+    <PackageReference Include="Ocelot" Version="10.0.3" />
     <PackageReference Include="StyleCop.Analyzers" Version="1.0.2">
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>