feat: reset proxy cache with sigusr2

internal/proxy/director/director.go

@@ -99,9 +99,12 @@ const proxiesCacheKey = "proxies"
 func (d *Director) getProxies(ctx context.Context) ([]*store.Proxy, error) {
 	proxies, exists := d.proxyCache.Get(proxiesCacheKey)
 	if exists {
+		logger.Debug(ctx, "using cached proxies")
 		return proxies, nil
 	}
 
+	logger.Debug(ctx, "querying fresh proxies")
+
 	headers, err := d.proxyRepository.QueryProxy(ctx, store.WithProxyQueryEnabled(true))
 	if err != nil {
 		return nil, errors.WithStack(err)
@@ -134,9 +137,12 @@ func (d *Director) getLayers(ctx context.Context, proxyName store.ProxyName) ([]
 
 	layers, exists := d.layerCache.Get(cacheKey)
 	if exists {
+		logger.Debug(ctx, "using cached layers")
 		return layers, nil
 	}
 
+	logger.Debug(ctx, "querying fresh layers")
+
 	headers, err := d.layerRepository.QueryLayers(ctx, proxyName, store.WithLayerQueryEnabled(true))
 	if err != nil {
 		return nil, errors.WithStack(err)

internal/proxy/server.go

@@ -13,8 +13,11 @@ import (
 	"net/http/httputil"
 	"net/http/pprof"
 	"net/url"
+	"os"
+	"os/signal"
 	"path/filepath"
 	"strconv"
+	"syscall"
 	"time"
 
 	"forge.cadoles.com/Cadoles/go-proxy"
@@ -94,24 +97,15 @@ func (s *Server) run(parentCtx context.Context, addrs chan net.Addr, errs chan e
 
 	logger.Info(ctx, "http server listening")
 
+	layerCache, proxyCache, cancel := s.createDirectorCaches(ctx)
+	defer cancel()
+
 	director := director.New(
 		s.proxyRepository,
 		s.layerRepository,
 		director.WithLayers(s.directorLayers...),
-		director.WithLayerCache(
-			ttl.NewCache(
-				memory.NewCache[string, []*store.Layer](),
-				memory.NewCache[string, time.Time](),
-				s.directorCacheTTL,
-			),
-		),
-		director.WithProxyCache(
-			ttl.NewCache(
-				memory.NewCache[string, []*store.Proxy](),
-				memory.NewCache[string, time.Time](),
-				s.directorCacheTTL,
-			),
-		),
+		director.WithLayerCache(layerCache),
+		director.WithProxyCache(proxyCache),
 		director.WithHandleErrorFunc(s.handleError),
 	)
 
@@ -205,6 +199,44 @@ func (s *Server) run(parentCtx context.Context, addrs chan net.Addr, errs chan e
 	logger.Info(ctx, "http server exiting")
 }
 
+func (s *Server) createDirectorCaches(ctx context.Context) (*ttl.Cache[string, []*store.Layer], *ttl.Cache[string, []*store.Proxy], func()) {
+	layerCache := ttl.NewCache(
+		memory.NewCache[string, []*store.Layer](),
+		memory.NewCache[string, time.Time](),
+		s.directorCacheTTL,
+	)
+
+	proxyCache := ttl.NewCache(
+		memory.NewCache[string, []*store.Proxy](),
+		memory.NewCache[string, time.Time](),
+		s.directorCacheTTL,
+	)
+
+	sig := make(chan os.Signal, 1)
+
+	signal.Notify(sig, syscall.SIGUSR2)
+
+	go func() {
+		for {
+			_, ok := <-sig
+			if !ok {
+				return
+			}
+
+			logger.Info(ctx, "received sigusr2 signal, clearing proxies and layers cache")
+
+			layerCache.Clear()
+			proxyCache.Clear()
+		}
+	}()
+
+	cancel := func() {
+		close(sig)
+	}
+
+	return layerCache, proxyCache, cancel
+}
+
 func (s *Server) createReverseProxy(ctx context.Context, target *url.URL) *httputil.ReverseProxy {
 	reverseProxy := httputil.NewSingleHostReverseProxy(target)