xopjson no longer buffers internally.

xopbytes has a richer API.

Incompatible changes:

- xopjson no longer supports WithBufferedLines()
- xopbytes.BytesWriter interface has additional and changed methods

  xopbytes.WriteToIOWriter() is unchanged

xopat/attributes.zzzgo

@@ -181,6 +181,7 @@ func (r Attribute) RegistrationNumber() int   { return r.number }
 func (r Attribute) ExampleValue() interface{} { return r.exampleValue }
 func (r Attribute) TypeName() string          { return r.typeName }
 func (r Attribute) SubType() AttributeType    { return r.subType }
+func (r *Attribute) Ptr() *Attribute          { return r }
 
 // EnumName only provides non-empty answers when SubType() == AttributeTypeEnum
 func (r Attribute) EnumName(v int64) string {

xopbytes/bytelogger.go

@@ -2,16 +2,41 @@
 package xopbytes
 
 import (
+	"time"
+
 	"github.com/xoplog/xop-go/trace"
+	"github.com/xoplog/xop-go/xopat"
+	"github.com/xoplog/xop-go/xopnum"
 )
 
 type BytesWriter interface {
 	Request(span trace.Bundle) BytesRequest
 	Buffered() bool
-	Close() // no point in returning an error
+	Close()                                      // no point in returning an error
+	DefineAttribute(*xopat.Attribute)            // duplicate calls should be ignored
+	DefineEnum(*xopat.EnumAttribute, xopat.Enum) // duplicate calls should be ignored
 }
 
 type BytesRequest interface {
 	Flush() error
-	Write([]byte) (int, error)
+	ReclaimMemory() // called when we know BytesRequest will never be used again
+	Span(Span, Buffer) error
+	Line(Line) error
+	AttributeReferenced(*xopat.Attribute) error
+}
+
+type Buffer interface {
+	AsBytes() []byte
+	ReclaimMemory()
+}
+
+type Line interface {
+	Buffer
+	GetSpanID() trace.HexBytes8
+	GetLevel() xopnum.Level
+	GetTime() time.Time
+}
+
+type Span interface {
+	GetSpanID() trace.HexBytes8
 }

xopbytes/iowriter.go

@@ -4,6 +4,7 @@ import (
 	"io"
 
 	"github.com/xoplog/xop-go/trace"
+	"github.com/xoplog/xop-go/xopat"
 )
 
 var _ BytesWriter = IOWriter{}
@@ -18,10 +19,23 @@ func WriteToIOWriter(w io.Writer) BytesWriter {
 	}
 }
 
-func (iow IOWriter) Buffered() bool                    { return false }
-func (iow IOWriter) Flush() error                      { return nil }
-func (iow IOWriter) Request(trace.Bundle) BytesRequest { return iow }
-
+func (iow IOWriter) Buffered() bool                               { return false }
+func (iow IOWriter) Flush() error                                 { return nil }
+func (iow IOWriter) ReclaimMemory()                               {}
+func (iow IOWriter) Request(trace.Bundle) BytesRequest            { return iow }
+func (iow IOWriter) DefineEnum(*xopat.EnumAttribute, xopat.Enum)  {}
+func (iow IOWriter) DefineAttribute(*xopat.Attribute)             {}
+func (iow IOWriter) AttributeReferenced(_ *xopat.Attribute) error { return nil }
+func (iow IOWriter) Line(line Line) error {
+	_, err := iow.Write(line.AsBytes())
+	line.ReclaimMemory()
+	return err
+}
+func (iow IOWriter) Span(_ Span, buffer Buffer) error {
+	_, err := iow.Write(buffer.AsBytes())
+	buffer.ReclaimMemory()
+	return err
+}
 func (iow IOWriter) Close() {
 	if wc, ok := iow.Writer.(io.WriteCloser); ok {
 		_ = wc.Close()