public async Task <byte[]> SerializeAsync(T data, SerializationContext context)
{
string subject = $"{context.Topic }-{context.Component}";
int id = 0;
var schema = AvroConvert.GenerateSchema(typeof(T));
if (cache.ContainsKey(subject))
{
id = cache[subject];
}
else
{
var existingSchema = await RegistryClient.GetLatestSchemaAsync(subject);
if (existingSchema.SchemaString == schema)
{
cache.AddOrUpdate(subject, existingSchema.Id, (key, oldValue) => existingSchema.Id);
}
else
{
Confluent.SchemaRegistry.Schema confluentSchema = new Confluent.SchemaRegistry.Schema(
subject,
existingSchema.Version + 1,
0,
schema
);
id = await RegistryClient.RegisterSchemaAsync(subject, confluentSchema.ToString());
cache.AddOrUpdate(subject, id, (key, oldValue) => id);
}
}
using (var stream = new MemoryStream())
{
//Confluent Kafka format:
//https://docs.confluent.io/current/schema-registry/docs/serializer-formatter.html#wire-format
//Magic number
stream.WriteByte(0x00);
//Id
var idAsBytes = BitConverter.GetBytes(id);
stream.Write(idAsBytes, 0, idAsBytes.Length);
//Data
var serializedData = AvroConvert.SerializeHeadless(data, schema);
stream.Write(serializedData, 0, serializedData.Length);
return(stream.ToArray());
}
}
/// <inheritdoc/> public async Task <bool> IsCompatibleAsync(string subject, Schema schema) => await restService.TestLatestCompatibilityAsync(subject, schema).ConfigureAwait(continueOnCapturedContext: false);
public async Task<bool> TestCompatibilityAsync(string subject, int versionId, Schema schema)
=> schema.SchemaType == SchemaType.Avro
// In the avro case, just send the schema string to maintain backards compatibility.
? (await RequestAsync<CompatibilityCheck>($"compatibility/subjects/{subject}/versions/{versionId}", HttpMethod.Post, new SchemaString(schema.SchemaString))
.ConfigureAwait(continueOnCapturedContext: false)).IsCompatible
: (await RequestAsync<CompatibilityCheck>($"compatibility/subjects/{subject}/versions/{versionId}", HttpMethod.Post, schema)
.ConfigureAwait(continueOnCapturedContext: false)).IsCompatible;
/// <inheritdoc/> public Task <RegisteredSchema> LookupSchemaAsync(string subject, Schema schema, bool ignoreDeletedSchemas) => restService.LookupSchemaAsync(subject, schema, ignoreDeletedSchemas);