inspector.go

package httpsling

import (
	"bytes"
	"io"
	"net/http"
)

// Inspect installs and returns an Inspector
func Inspect(r *Requester) *Inspector {
	i := Inspector{}
	r.MustApply(&i)

	return &i
}

// Inspector is a Requester Option which captures requests and responses
type Inspector struct {
	// The last request sent by the client
	Request *http.Request
	// The last response received by the client
	Response *http.Response
	// The last client request body
	RequestBody *bytes.Buffer
	// The last client response body
	ResponseBody *bytes.Buffer
}

// Clear clears the inspector's fields
func (i *Inspector) Clear() {
	if i == nil {
		return
	}

	i.RequestBody = nil
	i.ResponseBody = nil
	i.Request = nil
	i.Response = nil
}

// Apply implements Option
func (i *Inspector) Apply(r *Requester) error {
	return r.Apply(Middleware(i.Wrap))
}

// Wrap implements Middleware
func (i *Inspector) Wrap(next Doer) Doer {
	return DoerFunc(func(req *http.Request) (*http.Response, error) {
		i.Request = req

		req.Body = i.wrap(req.Body, true)

		resp, err := next.Do(req)
		i.Response = resp

		if resp != nil {
			resp.Body = i.wrap(resp.Body, false)
		}

		return resp, err
	})
}

func (i *Inspector) wrap(body io.ReadCloser, isRequest bool) io.ReadCloser {
	if body != nil {
		out, _ := io.ReadAll(body)
		body.Close()
		body = io.NopCloser(bytes.NewReader(out))

		if isRequest {
			i.RequestBody = bytes.NewBuffer(out)
		} else {
			i.ResponseBody = bytes.NewBuffer(out)
		}
	}

	return body
}