Add retry logic for Post, Patch and Delete to the HttpAbstractions

src/Core/HttpAbstractions.cs

@@ -1,4 +1,6 @@
 using System;
+using System.Linq;
+using System.Net;
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Text;
@@ -24,24 +26,29 @@ namespace Geekbot.Core
             return client;
         }
 
-        public static async Task<TResponse> Get<TResponse>(Uri location, HttpClient httpClient = null, bool disposeClient = true)
+        public static async Task<TResponse> Get<TResponse>(Uri location, HttpClient httpClient = null, bool disposeClient = true, int maxRetries = 3)
         {
             httpClient ??= CreateDefaultClient();
             httpClient.BaseAddress = location;
 
-            var response = await httpClient.GetAsync(location.PathAndQuery);
+            HttpResponseMessage response;
-            response.EnsureSuccessStatusCode();
+            try
-            var stringResponse = await response.Content.ReadAsStringAsync();
-
-            if (disposeClient)
             {
-                httpClient.Dispose();
+                response = await Execute(() => httpClient.GetAsync(location.PathAndQuery), maxRetries);
+            }
+            finally
+            {
+                if (disposeClient)
+                {
+                    httpClient.Dispose();
+                }
             }
 
+            var stringResponse = await response.Content.ReadAsStringAsync();
             return JsonSerializer.Deserialize<TResponse>(stringResponse);
         }
         
-        public static async Task<TResponse> Post<TResponse>(Uri location, object data, HttpClient httpClient = null, bool disposeClient = true)
+        public static async Task<TResponse> Post<TResponse>(Uri location, object data, HttpClient httpClient = null, bool disposeClient = true, int maxRetries = 3)
         {
             httpClient ??= CreateDefaultClient();
             httpClient.BaseAddress = location;
@@ -51,69 +58,131 @@ namespace Geekbot.Core
                 Encoding.UTF8,
                 "application/json"
             );
-            var response = await httpClient.PostAsync(location.PathAndQuery, content);
-            response.EnsureSuccessStatusCode();
-            var stringResponse = await response.Content.ReadAsStringAsync();
 
-            if (disposeClient)
+            HttpResponseMessage response;
+            try
             {
-                httpClient.Dispose();
+                response = await Execute(() => httpClient.PostAsync(location, content), maxRetries);
+            }
+            finally
+            {
+                if (disposeClient)
+                {
+                    httpClient.Dispose();
+                }
             }
 
+            var stringResponse = await response.Content.ReadAsStringAsync();
             return JsonSerializer.Deserialize<TResponse>(stringResponse);
         }
         
-        public static async Task Post(Uri location, object data, HttpClient httpClient = null, bool disposeClient = true)
+        public static async Task Post(Uri location, object data, HttpClient httpClient = null, bool disposeClient = true, int maxRetries = 3)
         {
             httpClient ??= CreateDefaultClient();
             httpClient.BaseAddress = location;
 
             var content = new StringContent(
-                System.Text.Json.JsonSerializer.Serialize(data, new JsonSerializerOptions() { DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull }),
+                JsonSerializer.Serialize(data, new JsonSerializerOptions() { DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull }),
                 Encoding.UTF8,
                 "application/json"
             );
 
-            var response = await httpClient.PostAsync(location, content);
+            try
-            response.EnsureSuccessStatusCode();
-
-            if (disposeClient)
             {
-                httpClient.Dispose();
+                await Execute(() => httpClient.PostAsync(location, content), maxRetries);
+            }
+            finally
+            {
+                if (disposeClient)
+                {
+                    httpClient.Dispose();
+                }
             }
         }
         
-        public static async Task Patch(Uri location, object data, HttpClient httpClient = null, bool disposeClient = true)
+        public static async Task Patch(Uri location, object data, HttpClient httpClient = null, bool disposeClient = true, int maxRetries = 3)
         {
             httpClient ??= CreateDefaultClient();
             httpClient.BaseAddress = location;
 
             var content = new StringContent(
-                System.Text.Json.JsonSerializer.Serialize(data, new JsonSerializerOptions() { DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull }),
+                JsonSerializer.Serialize(data, new JsonSerializerOptions() { DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull }),
                 Encoding.UTF8,
                 "application/json"
             );
 
-            var response = await httpClient.PatchAsync(location, content);
+            try
-            response.EnsureSuccessStatusCode();
-
-            if (disposeClient)
             {
-                httpClient.Dispose();
+                await Execute(() => httpClient.PatchAsync(location, content), maxRetries);
+            }
+            finally
+            {
+                if (disposeClient)
+                {
+                    httpClient.Dispose();
+                }
             }
         }
         
-        public static async Task Delete(Uri location, HttpClient httpClient = null, bool disposeClient = true)
+        public static async Task Delete(Uri location, HttpClient httpClient = null, bool disposeClient = true, int maxRetries = 3)
         {
             httpClient ??= CreateDefaultClient();
             httpClient.BaseAddress = location;
 
-            var response = await httpClient.DeleteAsync(location);
+            try
-            response.EnsureSuccessStatusCode();
-
-            if (disposeClient)
             {
-                httpClient.Dispose();
+                await Execute(() => httpClient.DeleteAsync(location), maxRetries);
+            }
+            finally
+            {
+                if (disposeClient)
+                {
+                    httpClient.Dispose();
+                }
+            }
+        }
+
+        private static async Task<HttpResponseMessage> Execute(Func<Task<HttpResponseMessage>> request, int maxRetries)
+        {
+            var attempt = 0;
+            while (true)
+            {
+                var response = await request();
+                if (!response.IsSuccessStatusCode)
+                {
+                    if (attempt >= maxRetries)
+                    {
+                        throw new HttpRequestException($"Request failed after {attempt} attempts");
+                    }
+                    
+                    if (response.Headers.Contains("Retry-After"))
+                    {
+                        var retryAfter = response.Headers.GetValues("Retry-After").First();
+                        if (retryAfter.Contains(':'))
+                        {
+                            var duration = DateTimeOffset.Parse(retryAfter).ToUniversalTime() - DateTimeOffset.Now.ToUniversalTime();
+                            await Task.Delay(duration);
+                        }
+                        else
+                        {
+                            await Task.Delay(int.Parse(retryAfter) * 1000);                            
+                        }
+                    }
+                    else if (response.StatusCode is HttpStatusCode.BadGateway or HttpStatusCode.ServiceUnavailable or HttpStatusCode.GatewayTimeout)
+                    {
+                        await Task.Delay(TimeSpan.FromSeconds(Math.Ceiling(attempt * 1.5)));
+                    }
+                    else
+                    {
+                        response.EnsureSuccessStatusCode();
+                    }
+                    
+                    attempt++;
+                }
+                else
+                {
+                    return response;
+                }
             }
         }
     }