offline-twitter/pkg/scraper/link_expander.go
2023-07-30 14:20:07 -03:00

35 lines
866 B
Go

package scraper
import (
"fmt"
"net/http"
"time"
)
/**
* Return the expanded version of a short URL. Input must be a real short URL.
*/
func ExpandShortUrl(short_url string) string {
// Create a client that doesn't follow redirects
client := &http.Client{
Timeout: 5 * time.Second,
CheckRedirect: func(req *http.Request, via []*http.Request) error {
return http.ErrUseLastResponse
},
}
resp, err := client.Get(short_url)
if err != nil {
panic(err) // TODO: handle timeouts
}
if resp.StatusCode != 301 {
panic(fmt.Errorf("Unknown status code returned when expanding short url %q: %s\n %w", short_url, resp.Status, EXTERNAL_API_ERROR))
}
long_url := resp.Header.Get("Location")
if long_url == "" {
panic(fmt.Errorf("Header didn't have a Location field for short url %q:\n %w", short_url, EXTERNAL_API_ERROR))
}
return long_url
}