21227: Fix copied mutexes.

[arvados.git] / services / keepproxy / keepproxy.go

diff --git a/services/keepproxy/keepproxy.go b/services/keepproxy/keepproxy.go
index 2090c506869d69419ffff32d14abf0aa7bfd58fd..a79883147b5c4dc95ddb003686f0d3f1d73b9240 100644 (file)
--- a/services/keepproxy/keepproxy.go
+++ b/services/keepproxy/keepproxy.go
@@ -175,13 +175,18 @@ func (h *proxyHandler) checkAuthorizationHeader(req *http.Request) (pass bool, t
        return true, tok, user
 }
 
-// We need to make a private copy of the default http transport early
-// in initialization, then make copies of our private copy later. It
-// won't be safe to copy http.DefaultTransport itself later, because
-// its private mutexes might have already been used. (Without this,
-// the test suite sometimes panics "concurrent map writes" in
-// net/http.(*Transport).removeIdleConnLocked().)
-var defaultTransport = *(http.DefaultTransport.(*http.Transport))
+// We can't copy the default http transport because http.Transport has
+// a mutex field, so we make our own using the values of the exported
+// fields.
+var defaultTransport = http.Transport{
+       Proxy:                 http.DefaultTransport.(*http.Transport).Proxy,
+       DialContext:           http.DefaultTransport.(*http.Transport).DialContext,
+       ForceAttemptHTTP2:     http.DefaultTransport.(*http.Transport).ForceAttemptHTTP2,
+       MaxIdleConns:          http.DefaultTransport.(*http.Transport).MaxIdleConns,
+       IdleConnTimeout:       http.DefaultTransport.(*http.Transport).IdleConnTimeout,
+       TLSHandshakeTimeout:   http.DefaultTransport.(*http.Transport).TLSHandshakeTimeout,
+       ExpectContinueTimeout: http.DefaultTransport.(*http.Transport).ExpectContinueTimeout,
+}
 
 type proxyHandler struct {
        http.Handler
@@ -195,14 +200,23 @@ type proxyHandler struct {
 func newHandler(ctx context.Context, kc *keepclient.KeepClient, timeout time.Duration, cluster *arvados.Cluster) (service.Handler, error) {
        rest := mux.NewRouter()
 
-       transport := defaultTransport
-       transport.DialContext = (&net.Dialer{
-               Timeout:   keepclient.DefaultConnectTimeout,
-               KeepAlive: keepclient.DefaultKeepAlive,
-               DualStack: true,
-       }).DialContext
-       transport.TLSClientConfig = arvadosclient.MakeTLSConfig(kc.Arvados.ApiInsecure)
-       transport.TLSHandshakeTimeout = keepclient.DefaultTLSHandshakeTimeout
+       // We can't copy the default http transport because
+       // http.Transport has a mutex field, so we copy the fields
+       // that we know have non-zero values in http.DefaultTransport.
+       transport := &http.Transport{
+               Proxy:                 http.DefaultTransport.(*http.Transport).Proxy,
+               ForceAttemptHTTP2:     http.DefaultTransport.(*http.Transport).ForceAttemptHTTP2,
+               MaxIdleConns:          http.DefaultTransport.(*http.Transport).MaxIdleConns,
+               IdleConnTimeout:       http.DefaultTransport.(*http.Transport).IdleConnTimeout,
+               ExpectContinueTimeout: http.DefaultTransport.(*http.Transport).ExpectContinueTimeout,
+               DialContext: (&net.Dialer{
+                       Timeout:   keepclient.DefaultConnectTimeout,
+                       KeepAlive: keepclient.DefaultKeepAlive,
+                       DualStack: true,
+               }).DialContext,
+               TLSClientConfig:     arvadosclient.MakeTLSConfig(kc.Arvados.ApiInsecure),
+               TLSHandshakeTimeout: keepclient.DefaultTLSHandshakeTimeout,
+       }
 
        cacheQ, err := lru.New2Q(500)
        if err != nil {
@@ -213,7 +227,7 @@ func newHandler(ctx context.Context, kc *keepclient.KeepClient, timeout time.Dur
                Handler:    rest,
                KeepClient: kc,
                timeout:    timeout,
-               transport:  &transport,
+               transport:  transport,
                apiTokenCache: &apiTokenCache{
                        tokens:     cacheQ,
                        expireTime: 300,
@@ -566,7 +580,7 @@ func (h *proxyHandler) Index(resp http.ResponseWriter, req *http.Request) {
 }
 
 func (h *proxyHandler) makeKeepClient(req *http.Request) *keepclient.KeepClient {
-       kc := *h.KeepClient
+       kc := h.KeepClient.Clone()
        kc.RequestID = req.Header.Get("X-Request-Id")
        kc.HTTPClient = &proxyClient{
                client: &http.Client{
@@ -575,5 +589,5 @@ func (h *proxyHandler) makeKeepClient(req *http.Request) *keepclient.KeepClient
                },
                proto: req.Proto,
        }
-       return &kc
+       return kc
 }