refactor: refactor Client constructor to support custom HttpClient and add validation for proxy and HttpClient conflicts

Author: Eirini

src/Tinify/Client.cs

@@ -32,7 +32,7 @@ internal sealed class ErrorData
 
         private readonly HttpClient _client;
 
-        public Client(string key, string appIdentifier = null, string proxy = null, HttpClient customHttpClient = null)
+        public Client(string key, string appIdentifier = null, string proxy = null)
         {
             var handler = new HttpClientHandler();
             if (proxy != null)
@@ -41,14 +41,36 @@ public Client(string key, string appIdentifier = null, string proxy = null, Http
                 handler.UseProxy = true;
             }
 
+            _client = new HttpClient(handler)
+            {
+                BaseAddress = ApiEndpoint,
+                Timeout = Timeout.InfiniteTimeSpan,
+            };
+
+
+            var userAgent = UserAgent;
+            if (appIdentifier != null)
+            {
+                userAgent += " " + appIdentifier;
+            }
+
+            _client.DefaultRequestHeaders.Add("User-Agent", userAgent);
+
+            var credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes("api:" + key));
+            _client.DefaultRequestHeaders.Add("Authorization", "Basic " + credentials);
+        }
+
+        public Client(string key, string appIdentifier = null, HttpClient customHttpClient = null)
+        {
+
             if (customHttpClient != null)
             {
                 _client = customHttpClient;
                 _client.BaseAddress = ApiEndpoint;
             }
             else
             {
-                _client = new HttpClient(handler)
+                _client = new HttpClient()
                 {
                     BaseAddress = ApiEndpoint,
                     Timeout = Timeout.InfiniteTimeSpan,
@@ -67,6 +89,8 @@ public Client(string key, string appIdentifier = null, string proxy = null, Http
             _client.DefaultRequestHeaders.Add("Authorization", "Basic " + credentials);
         }
 
+
+
         public Task<HttpResponseMessage> Request(Method method, string url)
         {
             return Request(method, new Uri(url, UriKind.Relative));

src/Tinify/Tinify.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Net.Http;
 using System.Threading.Tasks;
 
@@ -15,6 +16,25 @@ public class Tinify
         private static string key;
         private static string appIdentifier;
         private static string proxy;
+        private static HttpClient httpClient;
+
+        public static HttpClient HttpClient
+        {
+            get
+            {
+                return httpClient;
+            }
+
+            set
+            {
+                if (value != null && proxy != null)
+                {
+                    throw new ArgumentException("Cannot set HttpClient when Proxy is already configured. Please set either HttpClient or Proxy, not both.");
+                }
+                httpClient = value;
+                ResetClient();
+            }
+        }
 
         public static string Key
         {
@@ -53,6 +73,10 @@ public static string Proxy
 
             set
             {
+                if (value != null && httpClient != null)
+                {
+                    throw new ArgumentException("Cannot set Proxy when HttpClient is already configured. Please set either HttpClient or Proxy, not both.");
+                }
                 proxy = value;
                 ResetClient();
             }
@@ -88,7 +112,10 @@ public static Client Client
                     {
                         if (client == null)
                         {
-                            client = new Client(key, appIdentifier, proxy);
+                            if (httpClient != null)
+                                client = new Client(key, appIdentifier, httpClient);
+                            else
+                                client = new Client(key, appIdentifier, proxy);
                         }
                     }
                     return client;

test/Tinify.Tests/TinifyTest.cs

@@ -17,6 +17,7 @@ public void TearDown()
         {
             Tinify.Key = null;
             Tinify.Proxy = null;
+            Tinify.HttpClient = null;
         }
     }
 
@@ -124,6 +125,70 @@ public void WithInvalidProxy_Should_ThrowException()
         }
     }
 
+    [TestFixture]
+    public class Tinify_ProxyHttpClientConflict : Reset
+    {
+        [Test]
+        public void WithProxyFirst_HttpClientSecond_Should_ThrowException()
+        {
+            Tinify.Proxy = "http://localhost:8080";
+
+            var httpClient = new HttpClient();
+            var error = Assert.Throws<ArgumentException>(() =>
+            {
+                Tinify.HttpClient = httpClient;
+            });
+
+            Assert.AreEqual(
+                "Cannot set HttpClient when Proxy is already configured. Please set either HttpClient or Proxy, not both.",
+                error?.Message
+            );
+        }
+
+        [Test]
+        public void WithHttpClientFirst_ProxySecond_Should_ThrowException()
+        {
+            var httpClient = new HttpClient();
+            Tinify.HttpClient = httpClient;
+
+            var error = Assert.Throws<ArgumentException>(() =>
+            {
+                Tinify.Proxy = "http://localhost:8080";
+            });
+
+            Assert.AreEqual(
+                "Cannot set Proxy when HttpClient is already configured. Please set either HttpClient or Proxy, not both.",
+                error?.Message
+            );
+        }
+
+        [Test]
+        public void CanSetProxyAfterHttpClientIsCleared()
+        {
+            var httpClient = new HttpClient();
+            Tinify.HttpClient = httpClient;
+            Tinify.HttpClient = null;
+
+            Assert.DoesNotThrow(() =>
+            {
+                Tinify.Proxy = "http://localhost:8080";
+            });
+        }
+
+        [Test]
+        public void CanSetHttpClientAfterProxyIsCleared()
+        {
+            Tinify.Proxy = "http://localhost:8080";
+            Tinify.Proxy = null;
+
+            var httpClient = new HttpClient();
+            Assert.DoesNotThrow(() =>
+            {
+                Tinify.HttpClient = httpClient;
+            });
+        }
+    }
+
     [TestFixture]
     public class Tinify_Validate : Reset
     {
@@ -148,7 +213,7 @@ public void WithLimitedKey_Should_ReturnTrue()
 
             Helper.MockClient(Tinify.Client);
             Helper.MockHandler.Expect("https://api.tinify.com/shrink").Respond(
-                (HttpStatusCode) 429,
+                (HttpStatusCode)429,
                 new StringContent("{\"error\":\"Too may requests\",\"message\":\"Your monthly limit has been exceeded\"}")
             );