add RestClientSingleton

Author: J-W-Chan

.gitignore

@@ -350,3 +350,4 @@ MigrationBackup/
 .ionide/
 
 
+/.idea

Source/FikaAmazonAPI/AmazonSpApiSDK/Runtime/RestClientSingleton.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Net.Http;
+using RestSharp;
+
+namespace FikaAmazonAPI.AmazonSpApiSDK.Runtime
+{
+    public class RestClientSingleton
+    {
+        private static readonly HttpClient _httpClient = new HttpClient(new StandardSocketsHttpHandler
+        {
+            PooledConnectionLifetime = TimeSpan.FromMinutes(15)
+        });
+
+        static RestClientSingleton()
+        {
+        }
+
+        private RestClientSingleton()
+        {
+        }
+
+        public static RestClient RestClient => new RestClient(_httpClient);
+    }
+}

Source/FikaAmazonAPI/FikaAmazonAPI.csproj

@@ -38,9 +38,11 @@
     <PackageReference Include="AWSSDK.SecurityToken" Version="3.7.100.52" />
     <PackageReference Include="AWSSDK.SQS" Version="3.7.100.52" />
     <PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
+    <PackageReference Include="Microsoft.Extensions.Http" Version="7.0.0" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.2" />
     <PackageReference Include="RestSharp" Version="108.0.3" />
     <PackageReference Include="RestSharp.Serializers.NewtonsoftJson" Version="108.0.3" />
+    <PackageReference Include="StandardSocketsHttpHandler" Version="2.2.0.4" />
     <PackageReference Include="System.Collections" Version="4.3.0" />
     <PackageReference Include="System.ComponentModel.Annotations" Version="5.0.0" />
     <PackageReference Include="System.Reflection" Version="4.3.0" />