From 34e6254e1868b4b540f6b6b21cfaa23c7deb5647 Mon Sep 17 00:00:00 2001
From: Michael Yarichuk <michael.yarichuk@gmail.com>
Date: Sun, 3 May 2020 18:55:53 +0300
Subject: [PATCH] add convenience methods (adding multiple certificates at
 once, multiple policies at once, etc)

---
 Simple.HttpClientFactory/HttpClientBuilder.cs | 35 ++++++++++++++++++-
 .../IHttpClientBuilder.cs                     | 17 +++++++++
 2 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/Simple.HttpClientFactory/HttpClientBuilder.cs b/Simple.HttpClientFactory/HttpClientBuilder.cs
index 55f6d3f..4ef0daa 100644
--- a/Simple.HttpClientFactory/HttpClientBuilder.cs
+++ b/Simple.HttpClientFactory/HttpClientBuilder.cs
@@ -17,14 +17,37 @@ internal class HttpClientBuilder : IHttpClientBuilder
         private readonly List<X509Certificate2> _certificates = new List<X509Certificate2>();
         private readonly List<IAsyncPolicy<HttpResponseMessage>> _policies = new List<IAsyncPolicy<HttpResponseMessage>>();
         private readonly List<DelegatingHandler> _middlewareHandlers = new List<DelegatingHandler>();
+        private readonly Dictionary<string, string> _defaultHeaders = new Dictionary<string, string>();
 
+        public IHttpClientBuilder WithDefaultHeaders(IReadOnlyDictionary<string, string> headers)
+        {
+            foreach(var kvp in headers)
+            {
+                if(!_defaultHeaders.ContainsKey(kvp.Key))
+                    _defaultHeaders.Add(kvp.Key, kvp.Value);
+            }
+            return this;
+        }
 
+        public IHttpClientBuilder WithCertificates(IEnumerable<X509Certificate2> certificates)
+        {                        
+            _certificates.AddRange(certificates);
+            return this;
+        }
+        
         public IHttpClientBuilder WithCertificate(params X509Certificate2[] certificates)
         {                        
             _certificates.AddRange(certificates);
             return this;
         }
 
+        public IHttpClientBuilder WithPolicies(IEnumerable<IAsyncPolicy<HttpResponseMessage>> policies)
+        {
+            _policies.AddRange(policies);
+            return this;
+        }
+
+
         public IHttpClientBuilder WithPolicy(IAsyncPolicy<HttpResponseMessage> policy)
         {
             _policies.Add(policy);
@@ -130,7 +153,7 @@ public HttpClient Build(Action<HttpClientHandler> clientHandlerConfigurator = nu
             }
 
             var client = ConstructClientWithMiddleware(clientHandler, policyHandler);
-
+            
             if (_timeout.HasValue)
                 client.Timeout = _timeout.Value;
 
@@ -158,6 +181,16 @@ private HttpClient ConstructClientWithMiddleware<TClientHandler>(TClientHandler
             }
             else
                 client = new HttpClient(clientHandler, true);
+
+            if(_defaultHeaders.Count > 0)
+            {
+                foreach(var header in _defaultHeaders)
+                {
+                    if(!client.DefaultRequestHeaders.Contains(header.Key))
+                        client.DefaultRequestHeaders.Add(header.Key, header.Value);
+                }
+            }
+
             return client;
         }
     }
diff --git a/Simple.HttpClientFactory/IHttpClientBuilder.cs b/Simple.HttpClientFactory/IHttpClientBuilder.cs
index df0909a..f357a2d 100644
--- a/Simple.HttpClientFactory/IHttpClientBuilder.cs
+++ b/Simple.HttpClientFactory/IHttpClientBuilder.cs
@@ -1,5 +1,6 @@
 using Polly;
 using System;
+using System.Collections.Generic;
 using System.Net.Http;
 using System.Security.Cryptography.X509Certificates;
 
@@ -7,11 +8,27 @@ namespace Simple.HttpClientFactory
 {
     public interface IHttpClientBuilder
     {
+        /// <summary>
+        /// Add default headers to be added to teach request
+        /// </summary>
+        IHttpClientBuilder WithDefaultHeaders(IReadOnlyDictionary<string, string> headers);
+
+        /// <summary>
+        /// Configure one or more SSL certificates to use
+        /// </summary>
+        IHttpClientBuilder WithCertificates(IEnumerable<X509Certificate2> certificates);
+
         /// <summary>
         /// Configure one or more SSL certificates to use
         /// </summary>
         IHttpClientBuilder WithCertificate(params X509Certificate2[] certificates);
 
+        /// <summary>
+        /// Chain multiple Polly error policies
+        /// </summary>
+        /// <remarks>Policies will be evaluated in the order of their configuration</remarks>
+        IHttpClientBuilder WithPolicies(IEnumerable<IAsyncPolicy<HttpResponseMessage>> policies);
+
         /// <summary>
         /// Chain Polly error policy
         /// </summary>