scope/search/web/bing.go

134 lines
3.4 KiB
Go

/*
* Scope - A simple and minimal metasearch engine
* Copyright (C) 2021 Arsen Musayelyan
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
package web
import (
"net/http"
"strconv"
"github.com/PuerkitoBio/goquery"
)
var bingURL = urlMustParse("https://www.bing.com/search?count=10")
// Bing represents the Bing search engine
type Bing struct {
keyword string
userAgent string
first int
doc *goquery.Document
initDone bool
baseSel *goquery.Selection
}
// SetKeyword sets the keyword for searching
func (b *Bing) SetKeyword(keyword string) {
b.keyword = keyword
}
// SetPage sets the page number for searching
func (b *Bing) SetPage(page int) {
b.first = page * 10
}
// SetUserAgent sets the user agent to use for the request
func (b *Bing) SetUserAgent(ua string) {
b.userAgent = ua
}
// Init runs requests for Bing search engine
func (b *Bing) Init() error {
// Copy URL so it can be changed
initURL := copyURL(bingURL)
query := initURL.Query()
// Set query
query.Set("q", b.keyword)
if b.first > 0 {
query.Set("first", strconv.Itoa(b.first))
} else {
query.Set("first", "1")
}
// Update URL query parameters
initURL.RawQuery = query.Encode()
// Create new request for modified URL
req, err := http.NewRequest(
http.MethodGet,
initURL.String(),
nil,
)
if err != nil {
return err
}
// If no user agent, use default
if b.userAgent == "" {
b.userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36"
}
// Set request user agent
req.Header.Set("User-Agent", b.userAgent)
// Perform request
res, err := http.DefaultClient.Do(req)
if err != nil {
return err
}
defer res.Body.Close()
// Create new goquery document
doc, err := goquery.NewDocumentFromReader(res.Body)
if err != nil {
return err
}
b.doc = doc
b.baseSel = doc.Find(`#b_results > li`)
b.initDone = true
return nil
}
// Each runs eachCb with the index of each search result
func (b *Bing) Each(eachCb func(int) error) error {
for i := 0; i < b.baseSel.Length(); i++ {
err := eachCb(i)
if err != nil {
return err
}
}
return nil
}
// Title returns the title of the search result corresponding to i
func (b *Bing) Title(i int) (string, error) {
return get(b.baseSel, i).ChildrenFiltered("h2").Children().First().Text(), nil
}
// Link returns the link to the search result corresponding to i
func (b *Bing) Link(i int) (string, error) {
return get(b.baseSel, i).ChildrenFiltered("h2").Children().First().AttrOr("href", ""), nil
}
// Desc returns the description of the search result corresponding to i
func (b *Bing) Desc(i int) (string, error) {
return get(b.baseSel, i).ChildrenFiltered(".b_caption").Children().Last().Text(), nil
}
// Name returns "bing"
func (b *Bing) Name() string {
return "bing"
}