log/body_byte_counter.go

package log

import (
	"io"
	"sync/atomic"
)

// bodyByteCounter is a wrapper for http.Request.Body that counts bytes read.
type bodyByteCounter struct {
	body  io.ReadCloser
	count *atomic.Int64
}

// bodyByteCounter implements io.ReadCloser.
var _ io.ReadCloser = &bodyByteCounter{}

// Read implements the io.Reader interface, counting bytes as they are read.
func (c *bodyByteCounter) Read(p []byte) (int, error) {
	n, err := c.body.Read(p)
	c.count.Add(int64(n))

	return n, err
}

// Close implements the io.Closer interface.
func (c *bodyByteCounter) Close() error {
	return c.body.Close()
}