From 40511043bc5de3525b83961c78a22e9312a5f8bc Mon Sep 17 00:00:00 2001
From: Filipe Esch <filipe.esch@farfetch.com>
Date: Tue, 30 Mar 2021 16:41:25 +0100
Subject: [PATCH] feat: creates KafkaFlow.Extensions.Hosting to run as Hosted
 Service

---
 .../KafkaFlow.Extensions.Hosting.csproj       | 21 +++++++++++++++
 .../KafkaFlowHostedService.cs                 | 18 +++++++++++++
 .../ServiceCollectionExtensions.cs            | 26 +++++++++++++++++++
 src/KafkaFlow.sln                             |  7 +++++
 4 files changed, 72 insertions(+)
 create mode 100644 src/KafkaFlow.Extensions.Hosting/KafkaFlow.Extensions.Hosting.csproj
 create mode 100644 src/KafkaFlow.Extensions.Hosting/KafkaFlowHostedService.cs
 create mode 100644 src/KafkaFlow.Extensions.Hosting/ServiceCollectionExtensions.cs

diff --git a/src/KafkaFlow.Extensions.Hosting/KafkaFlow.Extensions.Hosting.csproj b/src/KafkaFlow.Extensions.Hosting/KafkaFlow.Extensions.Hosting.csproj
new file mode 100644
index 000000000..c1d0baa11
--- /dev/null
+++ b/src/KafkaFlow.Extensions.Hosting/KafkaFlow.Extensions.Hosting.csproj
@@ -0,0 +1,21 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>netstandard2.0</TargetFramework>
+        <LangVersion>latest</LangVersion>
+        <RootNamespace>KafkaFlow</RootNamespace>
+        <PackageId>KafkaFlow.Extensions.Hosting</PackageId>
+        <Description>Helper to run KafkaFlow as a Hosted Service</Description>
+        <PackageIconUrl>https://raw.githubusercontent.com/Farfetch/.github/master/images/fuse-logo-128.png</PackageIconUrl>
+    </PropertyGroup>
+
+    <ItemGroup>
+      <ProjectReference Include="..\KafkaFlow.Microsoft.DependencyInjection\KafkaFlow.Microsoft.DependencyInjection.csproj" />
+      <ProjectReference Include="..\KafkaFlow\KafkaFlow.csproj" />
+    </ItemGroup>
+
+    <ItemGroup>
+      <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="2.2.0" />
+    </ItemGroup>
+
+</Project>
diff --git a/src/KafkaFlow.Extensions.Hosting/KafkaFlowHostedService.cs b/src/KafkaFlow.Extensions.Hosting/KafkaFlowHostedService.cs
new file mode 100644
index 000000000..7a08e6b68
--- /dev/null
+++ b/src/KafkaFlow.Extensions.Hosting/KafkaFlowHostedService.cs
@@ -0,0 +1,18 @@
+namespace KafkaFlow
+{
+    using System;
+    using System.Threading;
+    using System.Threading.Tasks;
+    using global::Microsoft.Extensions.Hosting;
+
+    internal class KafkaFlowHostedService : IHostedService
+    {
+        private readonly IKafkaBus kafkaBus;
+
+        public KafkaFlowHostedService(IServiceProvider serviceProvider) => this.kafkaBus = serviceProvider.CreateKafkaBus();
+
+        public Task StartAsync(CancellationToken cancellationToken) => this.kafkaBus.StartAsync(cancellationToken);
+
+        public Task StopAsync(CancellationToken cancellationToken) => this.kafkaBus.StopAsync();
+    }
+}
diff --git a/src/KafkaFlow.Extensions.Hosting/ServiceCollectionExtensions.cs b/src/KafkaFlow.Extensions.Hosting/ServiceCollectionExtensions.cs
new file mode 100644
index 000000000..920fb2471
--- /dev/null
+++ b/src/KafkaFlow.Extensions.Hosting/ServiceCollectionExtensions.cs
@@ -0,0 +1,26 @@
+namespace KafkaFlow
+{
+    using System;
+    using global::Microsoft.Extensions.DependencyInjection;
+    using KafkaFlow.Configuration;
+
+    /// <summary>
+    /// </summary>
+    public static class ServiceCollectionExtensions
+    {
+        /// <summary>
+        /// Configures KafkaFlow to run as a Hosted Service
+        /// </summary>
+        /// <param name="services">Instance of <see cref="IServiceCollection"/></param>
+        /// <param name="kafka">A handler to configure KafkaFlow</param>
+        /// <returns></returns>
+        public static IServiceCollection AddKafkaFlowHostedService(
+            this IServiceCollection services,
+            Action<IKafkaConfigurationBuilder> kafka)
+        {
+            return services
+                .AddHostedService<KafkaFlowHostedService>()
+                .AddKafka(kafka);
+        }
+    }
+}
diff --git a/src/KafkaFlow.sln b/src/KafkaFlow.sln
index 409a02fa1..26e2277ba 100644
--- a/src/KafkaFlow.sln
+++ b/src/KafkaFlow.sln
@@ -65,6 +65,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "KafkaFlow.BatchConsume", "K
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "KafkaFlow.Sample.BatchConsume", "..\samples\KafkaFlow.Sample.BatchConsume\KafkaFlow.Sample.BatchConsume.csproj", "{DE8A8871-B19E-489D-8292-386A06A4CDFA}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "KafkaFlow.Extensions.Hosting", "KafkaFlow.Extensions.Hosting\KafkaFlow.Extensions.Hosting.csproj", "{7913342E-80FD-4094-B892-18DAA2E6948F}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -159,6 +161,10 @@ Global
 		{DE8A8871-B19E-489D-8292-386A06A4CDFA}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{DE8A8871-B19E-489D-8292-386A06A4CDFA}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{DE8A8871-B19E-489D-8292-386A06A4CDFA}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7913342E-80FD-4094-B892-18DAA2E6948F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7913342E-80FD-4094-B892-18DAA2E6948F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7913342E-80FD-4094-B892-18DAA2E6948F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7913342E-80FD-4094-B892-18DAA2E6948F}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -188,6 +194,7 @@ Global
 		{0A782A83-B66D-4B99-9BE2-2B18AAD2E03C} = {ED24B548-6F37-4283-A35B-F6015BFB7A34}
 		{C891D0DB-BE19-4D20-9E2F-61D413210F8D} = {ED24B548-6F37-4283-A35B-F6015BFB7A34}
 		{DE8A8871-B19E-489D-8292-386A06A4CDFA} = {303AE78F-6C96-4DF4-AC89-5C4FD53AFF0B}
+		{7913342E-80FD-4094-B892-18DAA2E6948F} = {068CB250-2804-4C7E-9490-17F432B9CE21}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {6AE955B5-16B0-41CF-9F12-66D15B3DD1AB}