feat(openai): 新增反序列化回调通知事件得扩展方法

src/SKIT.FlurlHttpClient.Wechat.OpenAI/Extensions/WechatOpenAIClientEventExtensions.cs

@@ -0,0 +1,143 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Xml.Linq;
+using System.Xml.Serialization;
+
+namespace SKIT.FlurlHttpClient.Wechat.OpenAI
+{
+    /// <summary>
+    /// 为 <see cref="WechatOpenAIClient"/> 提供回调通知事件的扩展方法。
+    /// </summary>
+    public static class WechatOpenAIClientEventExtensions
+    {
+        private class EncryptedWechatOpenAIEvent
+        {
+            [Newtonsoft.Json.JsonProperty("Encrypt")]
+            [System.Text.Json.Serialization.JsonPropertyName("Encrypt")]
+            public string EncryptedData { get; set; } = default!;
+
+            [Newtonsoft.Json.JsonProperty("TimeStamp")]
+            [System.Text.Json.Serialization.JsonPropertyName("TimeStamp")]
+            [System.Text.Json.Serialization.JsonConverter(typeof(System.Text.Json.Converters.NumericalStringConverter))]
+            public string Timestamp { get; set; } = default!;
+
+            [Newtonsoft.Json.JsonProperty("Nonce")]
+            [System.Text.Json.Serialization.JsonPropertyName("Nonce")]
+            public string Nonce { get; set; } = default!;
+
+            [Newtonsoft.Json.JsonProperty("MsgSignature")]
+            [System.Text.Json.Serialization.JsonPropertyName("MsgSignature")]
+            public string Signature { get; set; } = default!;
+        }
+
+        private static TEvent InnerDeserializeEventFromXml<TEvent>(this WechatOpenAIClient client, string callbackXml)
+            where TEvent : WechatOpenAIEvent
+        {
+            if (client == null) throw new ArgumentNullException(nameof(client));
+            if (string.IsNullOrEmpty(callbackXml)) throw new ArgumentNullException(callbackXml);
+
+            try
+            {
+                if (!Utilities.WxBizMsgCryptor.TryParseXml(callbackXml, out string? encryptedXml))
+                    throw new Exceptions.WechatOpenAIEventSerializationException("Encrypt event failed, because of empty encrypted data.");
+
+                callbackXml = Utilities.WxBizMsgCryptor.AESDecrypt(cipherText: encryptedXml!, encodingAESKey: client.Credentials.PushEncodingAESKey!, out _);
+
+                using var reader = new StringReader(callbackXml);
+
+                XmlSerializer xmlSerializer = new XmlSerializer(typeof(TEvent), new XmlRootAttribute("xml"));
+                return (TEvent)xmlSerializer.Deserialize(reader)!;
+            }
+            catch (WechatOpenAIException)
+            {
+                throw;
+            }
+            catch (Exception ex)
+            {
+                throw new Exceptions.WechatOpenAIEventSerializationException("Deserialize event failed. Please see the `InnerException` for more details.", ex);
+            }
+        }
+
+        /// <summary>
+        /// <para>从 XML 反序列化得到 <see cref="WechatOpenAIEvent"/> 对象。</para>
+        /// </summary>
+        /// <typeparam name="TEvent"></typeparam>
+        /// <param name="client"></param>
+        /// <param name="callbackXml"></param>
+        /// <returns></returns>
+        public static TEvent DeserializeEventFromXml<TEvent>(this WechatOpenAIClient client, string callbackXml)
+            where TEvent : WechatOpenAIEvent, WechatOpenAIEvent.Serialization.IXmlSerializable, new()
+        {
+            return InnerDeserializeEventFromXml<TEvent>(client, callbackXml);
+        }
+
+        /// <summary>
+        /// <para>从 XML 反序列化得到 <see cref="WechatOpenAIEvent"/> 对象。</para>
+        /// </summary>
+        /// <param name="client"></param>
+        /// <param name="callbackXml"></param>
+        /// <returns></returns>
+        public static WechatOpenAIEvent DeserializeEventFromXml(this WechatOpenAIClient client, string callbackXml)
+        {
+            return InnerDeserializeEventFromXml<WechatOpenAIEvent>(client, callbackXml);
+        }
+
+        /// <summary>
+        /// 将 <see cref="WechatOpenAIEvent"/> 对象序列化成 XML。
+        /// </summary>
+        /// <typeparam name="TEvent"></typeparam>
+        /// <param name="client"></param>
+        /// <param name="callbackModel"></param>
+        /// <returns></returns>
+        public static string SerializeEventToXml<TEvent>(this WechatOpenAIClient client, TEvent callbackModel)
+            where TEvent : WechatOpenAIEvent, WechatOpenAIEvent.Serialization.IXmlSerializable, new()
+        {
+            string xml;
+
+            try
+            {
+                using var stream = new MemoryStream();
+                using var writer = new System.Xml.XmlTextWriter(stream, Encoding.UTF8);
+                writer.Formatting = System.Xml.Formatting.None;
+
+                XmlSerializer xmlSerializer = new XmlSerializer(typeof(TEvent), new XmlRootAttribute("xml"));
+                XmlSerializerNamespaces xmlNamespace = new XmlSerializerNamespaces();
+                xmlNamespace.Add(string.Empty, string.Empty);
+                xmlSerializer.Serialize(writer, callbackModel, xmlNamespace);
+                writer.Flush();
+                xml = Encoding.UTF8.GetString(stream.ToArray());
+                xml = Regex.Replace(xml, "\\s+<\\w+ (xsi|d2p1):nil=\"true\"[^>]*/>", string.Empty, RegexOptions.IgnoreCase);
+                xml = Regex.Replace(xml, "<\\?xml[^>]*\\?>", string.Empty, RegexOptions.IgnoreCase);
+            }
+            catch (Exception ex)
+            {
+                throw new Exceptions.WechatOpenAIEventSerializationException("Serialize event failed. Please see the `InnerException` for more details.", ex);
+            }
+
+
+            if (string.IsNullOrEmpty(client.Credentials.PushEncodingAESKey))
+                throw new Exceptions.WechatOpenAIEventSerializationException("Encrypt event failed, because there is no encoding AES key.");
+            if (string.IsNullOrEmpty(client.Credentials.PushToken))
+                throw new Exceptions.WechatOpenAIEventSerializationException("Encrypt event failed, because there is no token.");
+
+            try
+            {
+                string cipher = Utilities.WxBizMsgCryptor.AESEncrypt(
+                    plainText: xml,
+                    encodingAESKey: client.Credentials.PushEncodingAESKey!,
+                    appId: client.Credentials.AppId!
+                );
+
+                xml = Utilities.WxBizMsgCryptor.WrapXml(sToken: client.Credentials.PushToken!, sMsgEncrypt: cipher);
+            }
+            catch (Exception ex)
+            {
+                throw new Exceptions.WechatOpenAIEventSerializationException("Encrypt event failed. Please see the `InnerException` for more details.", ex);
+            }
+
+            return xml;
+        }
+    }
+}