15721: Fix 503 on API.MaxConcurrentRequests==0 and empty response.

Arvados-DCO-1.1-Signed-off-by: Tom Clegg <tclegg@veritasgenetics.com>

diff --git a/lib/controller/handler_test.go b/lib/controller/handler_test.go
index d34df7f2c45918103949300ca6619027696b757f..5dc0b1e86f8f1ff66d689f19ad6ab7d7b699a3de 100644 (file)
--- a/lib/controller/handler_test.go
+++ b/lib/controller/handler_test.go
@@ -65,21 +65,27 @@ func (s *HandlerSuite) TestConfigExport(c *check.C) {
        s.cluster.SystemRootToken = "secret"
        s.cluster.Collections.BlobSigning = true
        s.cluster.Collections.BlobSigningTTL = arvados.Duration(23 * time.Second)
-       req := httptest.NewRequest("GET", "/arvados/v1/config", nil)
-       resp := httptest.NewRecorder()
-       s.handler.ServeHTTP(resp, req)
-       c.Check(resp.Code, check.Equals, http.StatusOK)
-       c.Check(resp.Header().Get("Access-Control-Allow-Origin"), check.Equals, `*`)
-       c.Check(resp.Header().Get("Access-Control-Allow-Methods"), check.Matches, `.*\bGET\b.*`)
-       c.Check(resp.Header().Get("Access-Control-Allow-Headers"), check.Matches, `.+`)
-       var cluster arvados.Cluster
-       c.Log(resp.Body.String())
-       err := json.Unmarshal(resp.Body.Bytes(), &cluster)
-       c.Check(err, check.IsNil)
-       c.Check(cluster.ManagementToken, check.Equals, "")
-       c.Check(cluster.SystemRootToken, check.Equals, "")
-       c.Check(cluster.Collections.BlobSigning, check.DeepEquals, true)
-       c.Check(cluster.Collections.BlobSigningTTL, check.Equals, arvados.Duration(23*time.Second))
+       for _, method := range []string{"GET", "OPTIONS"} {
+               req := httptest.NewRequest(method, "/arvados/v1/config", nil)
+               resp := httptest.NewRecorder()
+               s.handler.ServeHTTP(resp, req)
+               c.Check(resp.Code, check.Equals, http.StatusOK)
+               c.Check(resp.Header().Get("Access-Control-Allow-Origin"), check.Equals, `*`)
+               c.Check(resp.Header().Get("Access-Control-Allow-Methods"), check.Matches, `.*\bGET\b.*`)
+               c.Check(resp.Header().Get("Access-Control-Allow-Headers"), check.Matches, `.+`)
+               if method == "OPTIONS" {
+                       c.Check(resp.Body.String(), check.HasLen, 0)
+                       continue
+               }
+               var cluster arvados.Cluster
+               c.Log(resp.Body.String())
+               err := json.Unmarshal(resp.Body.Bytes(), &cluster)
+               c.Check(err, check.IsNil)
+               c.Check(cluster.ManagementToken, check.Equals, "")
+               c.Check(cluster.SystemRootToken, check.Equals, "")
+               c.Check(cluster.Collections.BlobSigning, check.DeepEquals, true)
+               c.Check(cluster.Collections.BlobSigningTTL, check.Equals, arvados.Duration(23*time.Second))
+       }
 }
 
 func (s *HandlerSuite) TestProxyDiscoveryDoc(c *check.C) {

diff --git a/sdk/go/httpserver/request_limiter.go b/sdk/go/httpserver/request_limiter.go
index 23e6e016d303bbc78abefcc39bfa0fb65b8ef0fe..8889453125c4753a62927f830c4e236ecbc272a6 100644 (file)
--- a/sdk/go/httpserver/request_limiter.go
+++ b/sdk/go/httpserver/request_limiter.go
@@ -76,8 +76,9 @@ func (h *limiterHandler) Max() int {
 func (h *limiterHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
        if cap(h.requests) == 0 {
                atomic.AddInt64(&h.count, 1)
+               defer atomic.AddInt64(&h.count, -1)
                h.handler.ServeHTTP(resp, req)
-               atomic.AddInt64(&h.count, -1)
+               return
        }
        select {
        case h.requests <- struct{}{}: