130 lines
2.8 KiB
Go
130 lines
2.8 KiB
Go
package redirect
|
|
|
|
import (
|
|
"net/http"
|
|
"net/url"
|
|
"regexp"
|
|
"strings"
|
|
|
|
"github.com/opentracing/opentracing-go/ext"
|
|
"github.com/traefik/traefik/v2/pkg/tracing"
|
|
"github.com/vulcand/oxy/utils"
|
|
)
|
|
|
|
type redirect struct {
|
|
next http.Handler
|
|
regex *regexp.Regexp
|
|
replacement string
|
|
permanent bool
|
|
errHandler utils.ErrorHandler
|
|
name string
|
|
}
|
|
|
|
// New creates a Redirect middleware.
|
|
func newRedirect(next http.Handler, regex, replacement string, permanent bool, name string) (http.Handler, error) {
|
|
re, err := regexp.Compile(regex)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return &redirect{
|
|
regex: re,
|
|
replacement: replacement,
|
|
permanent: permanent,
|
|
errHandler: utils.DefaultHandler,
|
|
next: next,
|
|
name: name,
|
|
}, nil
|
|
}
|
|
|
|
func (r *redirect) GetTracingInformation() (string, ext.SpanKindEnum) {
|
|
return r.name, tracing.SpanKindNoneEnum
|
|
}
|
|
|
|
func (r *redirect) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
|
|
oldURL := rawURL(req)
|
|
|
|
// If the Regexp doesn't match, skip to the next handler.
|
|
if !r.regex.MatchString(oldURL) {
|
|
r.next.ServeHTTP(rw, req)
|
|
return
|
|
}
|
|
|
|
// Apply a rewrite regexp to the URL.
|
|
newURL := r.regex.ReplaceAllString(oldURL, r.replacement)
|
|
|
|
// Parse the rewritten URL and replace request URL with it.
|
|
parsedURL, err := url.Parse(newURL)
|
|
if err != nil {
|
|
r.errHandler.ServeHTTP(rw, req, err)
|
|
return
|
|
}
|
|
|
|
if newURL != oldURL {
|
|
handler := &moveHandler{location: parsedURL, permanent: r.permanent}
|
|
handler.ServeHTTP(rw, req)
|
|
return
|
|
}
|
|
|
|
req.URL = parsedURL
|
|
|
|
// Make sure the request URI corresponds the rewritten URL.
|
|
req.RequestURI = req.URL.RequestURI()
|
|
r.next.ServeHTTP(rw, req)
|
|
}
|
|
|
|
type moveHandler struct {
|
|
location *url.URL
|
|
permanent bool
|
|
}
|
|
|
|
func (m *moveHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
|
|
rw.Header().Set("Location", m.location.String())
|
|
|
|
status := http.StatusFound
|
|
if req.Method != http.MethodGet {
|
|
status = http.StatusTemporaryRedirect
|
|
}
|
|
|
|
if m.permanent {
|
|
status = http.StatusMovedPermanently
|
|
if req.Method != http.MethodGet {
|
|
status = http.StatusPermanentRedirect
|
|
}
|
|
}
|
|
rw.WriteHeader(status)
|
|
_, err := rw.Write([]byte(http.StatusText(status)))
|
|
if err != nil {
|
|
http.Error(rw, err.Error(), http.StatusInternalServerError)
|
|
}
|
|
}
|
|
|
|
func rawURL(req *http.Request) string {
|
|
scheme := "http"
|
|
host := req.Host
|
|
port := ""
|
|
uri := req.RequestURI
|
|
|
|
schemeRegex := `^(https?):\/\/(\[[\w:.]+\]|[\w\._-]+)?(:\d+)?(.*)$`
|
|
re, _ := regexp.Compile(schemeRegex)
|
|
if re.Match([]byte(req.RequestURI)) {
|
|
match := re.FindStringSubmatch(req.RequestURI)
|
|
scheme = match[1]
|
|
|
|
if len(match[2]) > 0 {
|
|
host = match[2]
|
|
}
|
|
|
|
if len(match[3]) > 0 {
|
|
port = match[3]
|
|
}
|
|
|
|
uri = match[4]
|
|
}
|
|
|
|
if req.TLS != nil {
|
|
scheme = "https"
|
|
}
|
|
|
|
return strings.Join([]string{scheme, "://", host, port, uri}, "")
|
|
}
|