robots_txt_fetcher.go

package main

import (
	"fmt"
	"net/url"

	"github.com/temoto/robotstxt"
)

type robotsTxtFetcher struct {
	client httpClient
}

func newRobotsTxtFetcher(c httpClient) *robotsTxtFetcher {
	return &robotsTxtFetcher{c}
}

func (f *robotsTxtFetcher) Fetch(uu *url.URL) (*robotstxt.RobotsData, error) {
	u := *uu
	u.Path = "robots.txt"

	r, err := f.client.Get(&u)
	if err != nil {
		return nil, f.formatError(err)
	}

	bs, err := r.Body()
	if err != nil {
		return nil, f.formatError(err)
	}

	return robotstxt.FromBytes(bs)
}

func (*robotsTxtFetcher) formatError(err error) error {
	return fmt.Errorf("failed to fetch robots.txt: %v", err)
}