Files
x/metrics/service/service.go
T
ginuerzh bc3d12ec2c fix(metrics): add doc comments, fix labels mutation and nil returns, add idempotent Close, add nil guards, add tests
- Fix promMetrics.Gauge/Counter/Observer mutating caller's labels map by
  using maps.Copy instead of direct assignment
- Fix Gauge/Counter/Observer returning nil for unknown metric names
  (now return noop implementations)
- Fix metricService.Close() race with sync.Once for safe concurrent calls
- Fix SetDSCP returning nil instead of errUnsupport on unsupported ops
- Add nil guards to WrapConn, WrapPacketConn, WrapUDPConn, WrapListener
- Add doc comments to all exported symbols
- Add 45 unit tests (metrics, noop, prom, service, wrapper)
2026-05-24 22:50:41 +08:00

114 lines
2.4 KiB
Go

package service
import (
"net"
"net/http"
"sync"
"github.com/go-gost/core/auth"
"github.com/go-gost/core/service"
"github.com/prometheus/client_golang/prometheus/promhttp"
)
const (
// DefaultPath is the default HTTP path for the metrics endpoint.
DefaultPath = "/metrics"
)
type options struct {
path string
auther auth.Authenticator
}
// Option configures the metrics service.
type Option func(*options)
// PathOption sets the HTTP path for the metrics endpoint.
func PathOption(path string) Option {
return func(o *options) {
o.path = path
}
}
// AutherOption sets the authenticator for the metrics endpoint.
func AutherOption(auther auth.Authenticator) Option {
return func(o *options) {
o.auther = auther
}
}
type metricService struct {
s *http.Server
ln net.Listener
cclose chan struct{}
closeOnce sync.Once
closeErr error
}
// NewService creates a metrics Service that exposes Prometheus metrics over HTTP.
func NewService(network, addr string, opts ...Option) (service.Service, error) {
if network == "" {
network = "tcp"
}
ln, err := net.Listen(network, addr)
if err != nil {
return nil, err
}
var options options
for _, opt := range opts {
opt(&options)
}
if options.path == "" {
options.path = DefaultPath
}
mux := http.NewServeMux()
mux.Handle(options.path, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if options.auther != nil {
u, p, _ := r.BasicAuth()
if _, ok := options.auther.Authenticate(r.Context(), u, p, auth.WithService("@metrics")); !ok {
w.WriteHeader(http.StatusUnauthorized)
return
}
}
promhttp.Handler().ServeHTTP(w, r)
}))
return &metricService{
s: &http.Server{
Handler: mux,
},
ln: ln,
cclose: make(chan struct{}),
}, nil
}
// Serve starts the metrics HTTP server and blocks until the listener is closed.
func (s *metricService) Serve() error {
return s.s.Serve(s.ln)
}
// Addr returns the network address the metrics server is listening on.
func (s *metricService) Addr() net.Addr {
return s.ln.Addr()
}
// Close stops the metrics HTTP server. It is safe to call multiple times.
func (s *metricService) Close() error {
s.closeOnce.Do(func() {
close(s.cclose)
s.closeErr = s.s.Close()
})
return s.closeErr
}
// IsClosed reports whether the metrics service has been closed.
func (s *metricService) IsClosed() bool {
select {
case <-s.cclose:
return true
default:
return false
}
}