How to serialize object make the output the same as SerializeAsString() method of C++

[DinoStray]

In C++, I can call protobuf_object.SerializeAsString().
Which method is the same as above in nodejs? The following code is not correct.

            let out = pbObj.serializeBinary();
            let serializeStr = Buffer.from(out).toString();

[dibenede]

What are you trying to do with the output? Fundamentally, serializeBinary is giving you a Uint8Array, which Buffer.from seems ok with. However, Buffer.toString assumes utf8 encoding, which you can't guarantee.

I'm not particularly experience with node, but at a glance I think Buffer/Uint8Array in this circumstance is roughly the same as SerializeAsString's produced std::string (i.e. bag of bits).

If you're trying to pass this off to some API that truly needs a string, then I think you need to Base64 encode.

[DinoStray]

I change proto definition bytes xxx to string xxx then everything is ok. I think there is some bug while use bytes for nodejs.

[lukesandberg]

The problem is utf8 encoding as dibenede said. When you change your type to string that will get utf8 encoded when you call serializeBinary(), so when you wrap it in a buffer and call toString that will be reversed.

See https://nodejs.org/api/buffer.html#buftostringencoding-start-end

What are you actually trying to do? Why do you need a string?

On Thu, Mar 23, 2023 at 9:44 PM DinoStray @.***> wrote:

I change proto definition bytes xxx to string xxx then everything is ok. I think there is some bug while use bytes for nodejs.

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