func (b BodyString) Valid() bool {
	if b.Data == "" {
		return false
	}
	return true
}
Valid string body valid?
package request
import (
	"bytes"
	"encoding/json"
	"encoding/xml"
	"fmt"
	"io"
	"mime/multipart"
	"net/url"
	"os"
	"path"
	"github.com/monaco-io/request/context"
	"gopkg.in/yaml.v2"
)
type BodyString struct {
	Data string
}
func (b BodyString) Apply(ctx *context.Context) {
	bBytes := bytes.NewReader([]byte(b.Data))
	rc, ok := io.Reader(bBytes).(io.ReadCloser)
	if !ok && bBytes != nil {
		rc = io.NopCloser(bBytes)
	}
	ctx.Request.Body = rc
	ctx.Request.ContentLength = int64(bytes.NewBufferString(b.Data).Len())
}