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package exposurelocal
import (
"errors"
"net"
"net/http"
"net/url"
"strings"
"sync"
)
type Registry struct {
mu sync.RWMutex
routes map[string]route
}
type route struct {
host string
path string
handler http.Handler
}
func NewRegistry() *Registry { return &Registry{routes: map[string]route{}} }
func (r *Registry) Register(owner, host, path string, handler http.Handler) error {
if r == nil {
return errors.New("exposurelocal: the handler registry is nil")
}
owner = strings.TrimSpace(owner)
if owner == "" {
return errors.New("exposurelocal: a route needs an owner")
}
if handler == nil {
return errors.New("exposurelocal: a route needs a handler")
}
host = normalizeHost(host)
if host == "" {
return errors.New("exposurelocal: a route needs a host")
}
r.mu.Lock()
if r.routes == nil {
r.routes = map[string]route{}
}
r.routes[owner] = route{host: host, path: normalizePath(path), handler: handler}
r.mu.Unlock()
return nil
}
func (r *Registry) Remove(owner string) {
if r == nil {
return
}
r.mu.Lock()
delete(r.routes, owner)
r.mu.Unlock()
}
func (r *Registry) Lookup(rawHost, rawPath string) (http.Handler, bool) {
if r == nil {
return nil, false
}
host := normalizeHost(rawHost)
if host == "" {
return nil, false
}
target := normalizePath(rawPath)
r.mu.RLock()
defer r.mu.RUnlock()
var (
best http.Handler
bestLen = -1
bestOwn string
)
for owner, rt := range r.routes {
if rt.host != host || !pathMatches(rt.path, target) {
continue
}
if len(rt.path) > bestLen || (len(rt.path) == bestLen && owner < bestOwn) {
best, bestLen, bestOwn = rt.handler, len(rt.path), owner
}
}
return best, best != nil
}
func (r *Registry) HandlerFor(rawHost, rawPath string) (http.Handler, bool) {
return r.Lookup(rawHost, rawPath)
}
func (r *Registry) ServeHTTP(w http.ResponseWriter, req *http.Request) {
handler, ok := r.Lookup(req.Host, req.URL.Path)
if !ok {
http.NotFound(w, req)
return
}
handler.ServeHTTP(w, req)
}
func normalizeHost(raw string) string {
raw = strings.TrimSpace(raw)
if raw == "" {
return ""
}
if !strings.Contains(raw, "://") {
raw = "https://" + raw
}
u, err := url.Parse(raw)
if err != nil {
return ""
}
host := strings.ToLower(strings.TrimSuffix(u.Hostname(), "."))
if host == "" {
return ""
}
port := u.Port()
if port == "" || port == "80" || port == "443" {
return host
}
return net.JoinHostPort(host, port)
}
func pathMatches(prefix, target string) bool {
if prefix == "/" {
return true
}
return target == prefix || strings.HasPrefix(target, prefix+"/")
}
