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c++avro

Size of encoded avro message without encoding it

Is there a way to get the size of the encoded avro message without actually encoding it?

I'm using Avro 1.8.1 for C++.

I'm used to google protocol buffers where you can call ByteSize() on a protobuf to get the encoded size, so it's something similar i'm looking for.

Since the message in essence is a raw struct I get that the size cannot be retrieved from the message itself, but perhaps there is a helper method that i'm not aware of?

Solution

  • There is no way around it unfortunately...

    Here is an example showing how the size can be calculated by encoding the object:

    MyAvroStruct obj;

avro::EncoderPtr encoder = avro::binaryEncoder();
std::auto_ptr<avro::OutputStream> out = avro::memoryOutputStream(1);
encoder->init(*out);
avro::encode(*encoder, obj);
out->flush();
uint32_t bufferSize = out->byteCount();