using System; using System.Collections.Generic; using System.IO; using System.Text; using Newtonsoft.Json; using Newtonsoft.Json.Linq; using RabbitMQ.Client; using RabbitMQ.Client.Framing; namespace Tapeti.Cmd.Serialization { public class SingleFileJSONMessageSerializer : IMessageSerializer { private readonly Stream stream; private readonly bool disposeStream; private readonly Encoding encoding; private static readonly JsonSerializerSettings SerializerSettings = new JsonSerializerSettings { NullValueHandling = NullValueHandling.Ignore }; private readonly Lazy exportFile; public SingleFileJSONMessageSerializer(Stream stream, bool disposeStream, Encoding encoding) { this.stream = stream; this.disposeStream = disposeStream; this.encoding = encoding; exportFile = new Lazy(() => new StreamWriter(stream, encoding)); } public void Serialize(Message message) { var serializableMessage = new SerializableMessage(message); var serialized = JsonConvert.SerializeObject(serializableMessage, SerializerSettings); exportFile.Value.WriteLine(serialized); } public IEnumerable Deserialize() { using (var reader = new StreamReader(stream, encoding)) { while (!reader.EndOfStream) { var serialized = reader.ReadLine(); if (string.IsNullOrEmpty(serialized)) continue; var serializableMessage = JsonConvert.DeserializeObject(serialized); if (serializableMessage == null) continue; yield return serializableMessage.ToMessage(); } } } public void Dispose() { if (exportFile.IsValueCreated) exportFile.Value.Dispose(); if (disposeStream) stream.Dispose(); } // ReSharper disable MemberCanBePrivate.Local - used for JSON serialization // ReSharper disable NotAccessedField.Local // ReSharper disable FieldCanBeMadeReadOnly.Local private class SerializableMessage { public ulong DeliveryTag; public bool Redelivered; public string Exchange; public string RoutingKey; public string Queue; // ReSharper disable once FieldCanBeMadeReadOnly.Local - must be settable by JSON deserialization public SerializableMessageProperties Properties; public JObject Body; public byte[] RawBody; // ReSharper disable once UnusedMember.Global - used by JSON deserialization // ReSharper disable once UnusedMember.Local public SerializableMessage() { Properties = new SerializableMessageProperties(); } public SerializableMessage(Message fromMessage) { DeliveryTag = fromMessage.DeliveryTag; Redelivered = fromMessage.Redelivered; Exchange = fromMessage.Exchange; RoutingKey = fromMessage.RoutingKey; Queue = fromMessage.Queue; Properties = new SerializableMessageProperties(fromMessage.Properties); // If this is detected as a JSON message, include the object directly in the JSON line so that it is easier // to read and process in the output file. Otherwise simply include the raw data and let Newtonsoft encode it. // This does mean the message will be rewritten. If this is an issue, feel free to add a "raw" option to this tool // that forces the RawBody to be used. It is open-source after all :-). if (Properties.ContentType == "application/json") { try { Body = JObject.Parse(Encoding.UTF8.GetString(fromMessage.Body)); RawBody = null; } catch { // Fall back to using the raw body Body = null; RawBody = fromMessage.Body; } } else { Body = null; RawBody = fromMessage.Body; } } public Message ToMessage() { return new Message { DeliveryTag = DeliveryTag, Redelivered = Redelivered, Exchange = Exchange, RoutingKey = RoutingKey, Queue = Queue, Properties = Properties.ToBasicProperties(), Body = Body != null ? Encoding.UTF8.GetBytes(Body.ToString(Formatting.None)) : RawBody }; } } // IBasicProperties is finicky when it comes to writing it's properties, // so we need this normalized class to read and write it from and to JSON private class SerializableMessageProperties { public string AppId; public string ClusterId; public string ContentEncoding; public string ContentType; public string CorrelationId; public byte? DeliveryMode; public string Expiration; public IDictionary Headers; public string MessageId; public byte? Priority; public string ReplyTo; public long? Timestamp; public string Type; public string UserId; public SerializableMessageProperties() { } public SerializableMessageProperties(IBasicProperties fromProperties) { AppId = fromProperties.AppId; ClusterId = fromProperties.ClusterId; ContentEncoding = fromProperties.ContentEncoding; ContentType = fromProperties.ContentType; CorrelationId = fromProperties.CorrelationId; DeliveryMode = fromProperties.IsDeliveryModePresent() ? (byte?)fromProperties.DeliveryMode : null; Expiration = fromProperties.Expiration; MessageId = fromProperties.MessageId; Priority = fromProperties.IsPriorityPresent() ? (byte?) fromProperties.Priority : null; ReplyTo = fromProperties.ReplyTo; Timestamp = fromProperties.IsTimestampPresent() ? (long?)fromProperties.Timestamp.UnixTime : null; Type = fromProperties.Type; UserId = fromProperties.UserId; if (fromProperties.IsHeadersPresent()) { Headers = new Dictionary(); // This assumes header values are UTF-8 encoded strings. This is true for Tapeti. foreach (var pair in fromProperties.Headers) Headers.Add(pair.Key, Encoding.UTF8.GetString((byte[])pair.Value)); } else Headers = null; } public IBasicProperties ToBasicProperties() { var properties = new BasicProperties(); if (!string.IsNullOrEmpty(AppId)) properties.AppId = AppId; if (!string.IsNullOrEmpty(ClusterId)) properties.ClusterId = ClusterId; if (!string.IsNullOrEmpty(ContentEncoding)) properties.ContentEncoding = ContentEncoding; if (!string.IsNullOrEmpty(ContentType)) properties.ContentType = ContentType; if (DeliveryMode.HasValue) properties.DeliveryMode = DeliveryMode.Value; if (!string.IsNullOrEmpty(Expiration)) properties.Expiration = Expiration; if (!string.IsNullOrEmpty(MessageId)) properties.MessageId = MessageId; if (Priority.HasValue) properties.Priority = Priority.Value; if (!string.IsNullOrEmpty(ReplyTo)) properties.ReplyTo = ReplyTo; if (Timestamp.HasValue) properties.Timestamp = new AmqpTimestamp(Timestamp.Value); if (!string.IsNullOrEmpty(Type)) properties.Type = Type; if (!string.IsNullOrEmpty(UserId)) properties.UserId = UserId; // ReSharper disable once InvertIf if (Headers != null) { properties.Headers = new Dictionary(); foreach (var pair in Headers) properties.Headers.Add(pair.Key, Encoding.UTF8.GetBytes(pair.Value)); } return properties; } } // ReSharper restore FieldCanBeMadeReadOnly.Local // ReSharper restore NotAccessedField.Local // ReSharper restore MemberCanBePrivate.Local } }