Parse error response and add to exception object

Author: KoditkarVedant

Src/Notion.Client/NotionAPIErrorCode.cs

@@ -0,0 +1,43 @@
+using System.Runtime.Serialization;
+
+namespace Notion.Client
+{
+    public enum NotionAPIErrorCode
+    {
+        [EnumMember(Value = "invalid_json")]
+        InvalidJSON,
+
+        [EnumMember(Value = "invalid_request_url")]
+        InvalidRequestURL,
+
+        [EnumMember(Value = "invalid_request")]
+        InvalidRequest,
+
+        [EnumMember(Value = "validation_error")]
+        ValidationError,
+
+        [EnumMember(Value = "missing_version")]
+        MissingVersion,
+
+        [EnumMember(Value = "unauthorized")]
+        Unauthorized,
+
+        [EnumMember(Value = "restricted_resource")]
+        RestrictedResource,
+
+        [EnumMember(Value = "object_not_found")]
+        ObjectNotFound,
+
+        [EnumMember(Value = "conflict_error")]
+        ConflictError,
+
+        [EnumMember(Value = "rate_limited")]
+        RateLimited,
+
+        [EnumMember(Value = "internal_server_error")]
+        InternalServerError,
+
+        [EnumMember(Value = "service_unavailable")]
+        ServiceUnavailable,
+    }
+}

Src/Notion.Client/NotionApiErrorResponse.cs

@@ -0,0 +1,8 @@
+namespace Notion.Client
+{
+    class NotionApiErrorResponse
+    {
+        public NotionAPIErrorCode ErrorCode { get; set; }
+        public string Message { get; set; }
+    }
+}

Src/Notion.Client/NotionApiException.cs

@@ -3,15 +3,32 @@
 
 namespace Notion.Client
 {
-    class NotionApiException : Exception
+    public class NotionApiException : Exception
     {
-        public NotionApiException(HttpStatusCode statusCode, string message) : this(statusCode, message, null)
+        public NotionApiException(HttpStatusCode statusCode, NotionAPIErrorCode? notionAPIErrorCode, string message)
+            : this(statusCode, notionAPIErrorCode, message, null)
         {
         }
 
-        public NotionApiException(HttpStatusCode statusCode, string message, Exception innerException) : base(message, innerException)
+        public NotionApiException(HttpStatusCode statusCode, string message)
+            : this(statusCode, null, message, null)
         {
+        }
+
+        public NotionApiException(
+            HttpStatusCode statusCode,
+            NotionAPIErrorCode? notionAPIErrorCode,
+            string message,
+            Exception innerException) : base(message, innerException)
+        {
+            NotionAPIErrorCode = notionAPIErrorCode;
+            StatusCode = statusCode;
+
             Data.Add("StatusCode", statusCode);
+            Data.Add("NotionApiErrorCode", NotionAPIErrorCode);
         }
+
+        public NotionAPIErrorCode? NotionAPIErrorCode { get; }
+        public HttpStatusCode StatusCode { get; }
     }
 }

Src/Notion.Client/RestClient/RestClient.cs

@@ -54,16 +54,26 @@ public async Task<T> GetAsync<T>(
 
             var response = await SendAsync(requestUri, HttpMethod.Get, headers, cancellationToken: cancellationToken);
 
-            if (response.IsSuccessStatusCode)
+            return await response.ParseStreamAsync<T>(serializerSettings);
+        }
+
+        private static async Task<Exception> BuildException(HttpResponseMessage response)
+        {
+            var errorBody = await response.Content.ReadAsStringAsync();
+
+            NotionApiErrorResponse errorResponse = null;
+            if (!string.IsNullOrWhiteSpace(errorBody))
             {
-                return await response.ParseStreamAsync<T>(serializerSettings);
+                try
+                {
+                    errorResponse = JsonConvert.DeserializeObject<NotionApiErrorResponse>(errorBody);
+                }
+                catch
+                {
+                }
             }
 
-            var message = !string.IsNullOrWhiteSpace(response.ReasonPhrase)
-                    ? response.ReasonPhrase
-                    : await response.Content.ReadAsStringAsync();
-
-            throw new NotionApiException(response.StatusCode, message);
+            return new NotionApiException(response.StatusCode, errorResponse?.ErrorCode, errorResponse.Message);
         }
 
         private async Task<HttpResponseMessage> SendAsync(
@@ -84,7 +94,14 @@ private async Task<HttpResponseMessage> SendAsync(
 
             attachContent?.Invoke(httpRequest);
 
-            return await _httpClient.SendAsync(httpRequest, cancellationToken);
+            var response = await _httpClient.SendAsync(httpRequest, cancellationToken);
+
+            if (!response.IsSuccessStatusCode)
+            {
+                throw await BuildException(response);
+            }
+
+            return response;
         }
 
         private static void AddHeaders(HttpRequestMessage request, IDictionary<string, string> headers)
@@ -114,16 +131,7 @@ void AttachContent(HttpRequestMessage httpRequest)
 
             var response = await SendAsync(requestUri, HttpMethod.Post, headers, AttachContent, cancellationToken: cancellationToken);
 
-            if (response.IsSuccessStatusCode)
-            {
-                return await response.ParseStreamAsync<T>(serializerSettings);
-            }
-
-            var message = !string.IsNullOrWhiteSpace(response.ReasonPhrase)
-                    ? response.ReasonPhrase
-                    : await response.Content.ReadAsStringAsync();
-
-            throw new NotionApiException(response.StatusCode, message);
+            return await response.ParseStreamAsync<T>(serializerSettings);
         }
 
         public async Task<T> PatchAsync<T>(string uri, object body, IDictionary<string, string> queryParams = null, IDictionary<string, string> headers = null, JsonSerializerSettings serializerSettings = null, CancellationToken cancellationToken = default)
@@ -140,18 +148,7 @@ void AttachContent(HttpRequestMessage httpRequest)
 
             var response = await SendAsync(requestUri, new HttpMethod("PATCH"), headers, AttachContent, cancellationToken: cancellationToken);
 
-            if (response.IsSuccessStatusCode)
-            {
-                return await response.ParseStreamAsync<T>(serializerSettings);
-            }
-
-            var message = !string.IsNullOrWhiteSpace(response.ReasonPhrase)
-                    ? response.ReasonPhrase
-                    : await response.Content.ReadAsStringAsync();
-
-            var errorMessage = await response.Content.ReadAsStringAsync();
-
-            throw new NotionApiException(response.StatusCode, message);
+            return await response.ParseStreamAsync<T>(serializerSettings);
         }
 
         private HttpClient EnsureHttpClient()