Is there a plan to expose the internal decoder for buffer use case?

[spacewander]

In the current implementation, each Unmarshal will create a new decoder:

sonic/sonic.go

Lines 113 to 124 in 4a3e8af

	func (cfg frozenConfig) UnmarshalFromString(buf string, val interface{}) error {
	dec := decoder.NewDecoder(buf)
	dec.SetOptions(cfg.decoderOpts)
	err := dec.Decode(val)
	/* check for errors */
	if err != nil {
	return err
	}
	return dec.CheckTrailings()
	}

There is already a Reset method in the underlying decoder, however, only the streaming decoder can call it:

sonic/internal/decoder/api/stream.go

Line 90 in 4a3e8af

self.Decoder.Reset(string(self.buf[s:e]))

In our scene, we process fixed JSON string and want to cache the decoder instead of creating a new one each call. Wrapping the fixed JSON strings as an io stream is unavailable so we can't use StreamDecoder.

It would be helpful to provide a way to expose the internal decoder, for example, under the name "BufferDecoder" and so on. We would like to contribute if this is acceptable.

[AsterDY]

I didn't get it. Decoder only holds the string you pass, there is no buffer..

[spacewander]

What I mean by using "buffer" is to refer to a new kind of Decoder that is different from the current exposed Decoder.

In the current implementation, the NewDecoder always returns a StreamDecoder:

sonic/sonic.go

Lines 139 to 143 in e2ff8ac

	func (cfg frozenConfig) NewDecoder(reader io.Reader) Decoder {
	dec := decoder.NewStreamDecoder(reader)
	dec.SetOptions(cfg.decoderOpts)
	return dec
	}

The StreamDecoder accepts an IO stream, and decodes data from it.

Meanwhile, there could be a BufferDecoder, which accepts a JSON string and uses Reset to clear the state when it wants to decode another JSON string.

[AsterDY]

Why not directly use sonic/decoder/NewDecoder()? It can do everythin including set options

[spacewander]

Thanks! That's what I need.