/// <summary>
/// Serialize an instance of type <see cref="T"/> to a byte array in avro format. The serialized
/// data is preceeded by a "magic byte" (1 byte) and the id of the schema as registered
/// in Confluent's Schema Registry (4 bytes, network byte order). This call may block or throw
/// on first use for a particular topic during schema registration.
/// </summary>
/// <param name="topic">
/// The topic associated wih the data.
/// </param>
/// <param name="data">
/// The object to serialize.
/// </param>
/// <returns>
/// <paramref name="data" /> serialized as a byte array.
/// </returns>
public byte[] Serialize(string topic, T data)
{
if (!topicsRegistered.Contains(topic))
{
string subject = IsKey
? SchemaRegistryClient.ConstructKeySubjectName(topic)
: SchemaRegistryClient.ConstructValueSubjectName(topic);
// first usage: register/get schema to check compatibility
if (AutoRegisterSchema)
{
SchemaId = SchemaRegistryClient.RegisterSchemaAsync(subject, writerSchemaString).Result;
}
else
{
SchemaId = SchemaRegistryClient.GetSchemaIdAsync(subject, writerSchemaString).Result;
}
topicsRegistered.Add(topic);
}
using (var stream = new MemoryStream(InitialBufferSize))
using (var writer = new BinaryWriter(stream))
{
stream.WriteByte(Constants.MagicByte);
writer.Write(IPAddress.HostToNetworkOrder(SchemaId.Value));
avroWriter.Write(data, new BinaryEncoder(stream));
// TODO: maybe change the ISerializer interface so that this copy isn't necessary.
return(stream.ToArray());
}
}
protected override async Task <int> OnExecute(CommandLineApplication app)
{
//Topic = "cc_payments";
//Key = false;
if (SchemaId.HasValue)
{
var schema = await SchemaRegistryClient.GetSchemaAsync(SchemaId.Value);
Output($"SCHM: {schema}");
return(1);
}
else
{
if (string.IsNullOrEmpty(Topic))
{
return(-1);
}
var schemaName = Key ? SchemaRegistryClient.ConstructKeySubjectName(Topic) : SchemaRegistryClient.ConstructValueSubjectName(Topic);
var schema = await SchemaRegistryClient.GetLatestSchemaAsync(schemaName);
var header = $"Subject: {schema.Subject} | ID: {schema.Id} | Version: {schema.Version}";
Output($"INFO: {header}");
Output($"SCHM: {schema.SchemaString}");
return(1);
}
}