go-paste/src/routes/shorturl.go
2020-08-28 16:02:12 -06:00

121 lines
2.3 KiB
Go

package routes
import (
"net/http"
"net/url"
"regexp"
"time"
"github.com/gorilla/mux"
"github.com/patrickmn/go-cache"
"sour.is/x/toolbox/httpsrv"
"sour.is/x/toolbox/uuid"
)
func init() {
s := NewShortManager(365 * 24 * time.Hour)
httpsrv.HttpRegister("short", httpsrv.HttpRoutes{
{Name: "getShort", Method: "GET", Pattern: "/s/{id}", HandlerFunc: s.getShort},
{Name: "putShort", Method: "PUT", Pattern: "/s/{id}", HandlerFunc: s.putShort},
})
}
type shortManager struct {
defaultExpire time.Duration
db *cache.Cache
}
type shortURL struct {
ID string
URL string
Secret string
}
func NewShortManager(defaultExpire time.Duration) *shortManager {
return &shortManager{
defaultExpire: defaultExpire,
db: cache.New(defaultExpire, defaultExpire/10),
}
}
func (s *shortManager) GetURL(id string) *shortURL {
if u, ok := s.db.Get(id); ok {
if url, ok := u.(*shortURL); ok {
return url
}
}
return nil
}
func (s *shortManager) PutURL(id string, url *shortURL) {
s.db.SetDefault(id, url)
}
func (s *shortManager) getShort(w http.ResponseWriter, r *http.Request) {
vars := mux.Vars(r)
id := vars["id"]
url := s.GetURL(id)
if url == nil {
httpsrv.WriteError(w, 404, "not found")
return
}
w.Header().Set("Location", url.URL)
w.WriteHeader(http.StatusFound)
}
func (s *shortManager) putShort(w http.ResponseWriter, r *http.Request) {
defer r.Body.Close()
vars := mux.Vars(r)
id := vars["id"]
secret := r.FormValue("secret")
u, err := url.Parse(r.FormValue("url"))
if err != nil {
httpsrv.WriteError(w, 400, "bad url")
return
}
short := s.GetURL(id)
if short == nil {
short = newshort(id, secret, u.String())
s.PutURL(short.ID, short)
httpsrv.WriteObject(w, 200, short)
return
}
if secret == "" {
httpsrv.WriteError(w, 401, "no auth")
return
}
if secret != short.Secret {
httpsrv.WriteError(w, 403, "forbidden")
return
}
short.URL = u.String()
s.PutURL(short.ID, short)
httpsrv.WriteObject(w, 200, short)
}
func newshort(id, secret, u string) *shortURL {
m, err := regexp.MatchString("[a-z-]{1,64}", id)
if id == "" || !m || err != nil {
id = uuid.V4()
}
m, err = regexp.MatchString("[a-z-]{1,64}", secret)
if secret == "" || !m || err != nil {
secret = uuid.V4()
}
return &shortURL{ID: id, Secret: secret, URL: u}
}