upgrade to latest dependencies

```
bumping knative.dev/hack 4ed1ecb...ea9c9a0:
  > ea9c9a0 Add hermetic go mod aware handling to run_go_tool (knative#38)
bumping knative.dev/networking ecb89ce...c30dc94:
  > c30dc94 Use symlink for testdata version of config-network.yaml (knative#328)
bumping knative.dev/pkg 51c72e2...93874f0:
  > 93874f0 Drainer supports customized kubelet probe check (knative#1977)
```

Signed-off-by: Knative Automation <automation@knative.team>

go.mod

@@ -34,8 +34,8 @@ require (
 	k8s.io/code-generator v0.18.12
 	k8s.io/kube-openapi v0.0.0-20200410145947-bcb3869e6f29
 	knative.dev/caching v0.0.0-20210107021736-1ee47505018d
-	knative.dev/hack v0.0.0-20201214230143-4ed1ecb8db24
-	knative.dev/networking v0.0.0-20210107024535-ecb89ced52d9
-	knative.dev/pkg v0.0.0-20210107022335-51c72e24c179
+	knative.dev/hack v0.0.0-20210108203236-ea9c9a0cac5c
+	knative.dev/networking v0.0.0-20210111171437-c30dc94f1dcf
+	knative.dev/pkg v0.0.0-20210107211936-93874f0ea7c0
 	sigs.k8s.io/yaml v1.2.0
 )

go.sum

@@ -1227,12 +1227,14 @@ knative.dev/caching v0.0.0-20210107021736-1ee47505018d h1:C5JgxpCO4Dv+pqUHxIS+e+
 knative.dev/caching v0.0.0-20210107021736-1ee47505018d/go.mod h1:N3jOlbf/CWZsEcfEpthv5b+LB9e+TqiDTVLH/Ti+vWE=
 knative.dev/hack v0.0.0-20201214230143-4ed1ecb8db24 h1:kIztWfvnIFV8Lhlea02K3YO2mIzcDyQNzrBLn0Oq9sA=
 knative.dev/hack v0.0.0-20201214230143-4ed1ecb8db24/go.mod h1:PHt8x8yX5Z9pPquBEfIj0X66f8iWkWfR0S/sarACJrI=
-knative.dev/networking v0.0.0-20210107024535-ecb89ced52d9 h1:7SXik2ulHr7URICeDYHPVdnyuT72RW9GouJ97XRkWbo=
-knative.dev/networking v0.0.0-20210107024535-ecb89ced52d9/go.mod h1:N123KICErXy+bPo1oBszM6TVYGG0Za2wMmnEqX4MlFg=
+knative.dev/hack v0.0.0-20210108203236-ea9c9a0cac5c h1:B/FwfbGrZRCwujjxVzFCc1sqNcAGL5oOm0ZkSSovSU8=
+knative.dev/hack v0.0.0-20210108203236-ea9c9a0cac5c/go.mod h1:PHt8x8yX5Z9pPquBEfIj0X66f8iWkWfR0S/sarACJrI=
+knative.dev/networking v0.0.0-20210111171437-c30dc94f1dcf h1:s55gnmWT87q0bf/hNQXGomBQrB9pyFVsoDGayT5itgg=
+knative.dev/networking v0.0.0-20210111171437-c30dc94f1dcf/go.mod h1:N123KICErXy+bPo1oBszM6TVYGG0Za2wMmnEqX4MlFg=
 knative.dev/pkg v0.0.0-20201224024804-27db5ac24cfb h1:XVcmpSvfDMZ5Z+1pebSm5Msq5sQey/V4NHF2+dFNU1o=
 knative.dev/pkg v0.0.0-20201224024804-27db5ac24cfb/go.mod h1:hckgW978SdzPA2H5EDvRPY8xsnPuDZLJLbPf8Jte7Q0=
-knative.dev/pkg v0.0.0-20210107022335-51c72e24c179 h1:lkrgrv69iUk2qhOG9symy15kJUaJZmMybSloi7C3gIw=
-knative.dev/pkg v0.0.0-20210107022335-51c72e24c179/go.mod h1:hckgW978SdzPA2H5EDvRPY8xsnPuDZLJLbPf8Jte7Q0=
+knative.dev/pkg v0.0.0-20210107211936-93874f0ea7c0 h1:oLySohpGJOAo7LFCKpGEn1JOtZkzZ6QS8tQ03Pgll/0=
+knative.dev/pkg v0.0.0-20210107211936-93874f0ea7c0/go.mod h1:hckgW978SdzPA2H5EDvRPY8xsnPuDZLJLbPf8Jte7Q0=
 modernc.org/cc v1.0.0/go.mod h1:1Sk4//wdnYJiUIxnW8ddKpaOJCF37yAdqYnkxUpaYxw=
 modernc.org/golex v1.0.0/go.mod h1:b/QX9oBD/LhixY6NDh+IdGv17hgB+51fET1i2kPSmvk=
 modernc.org/mathutil v1.0.0/go.mod h1:wU0vUrJsVWBZ4P6e7xtFJEhFSNsfRLJ8H458uRjg03k=

vendor/knative.dev/hack/library.sh

@@ -490,24 +490,37 @@ function start_latest_eventing_sugar_controller() {
 function run_go_tool() {
   local tool=$2
   local install_failed=0
-  if [[ -z "$(which ${tool})" ]]; then
-    local action=get
-    [[ $1 =~ ^[\./].* ]] && action=install
-    # Avoid running `go get` from root dir of the repository, as it can change go.sum and go.mod files.
-    # See discussions in https://github.com/golang/go/issues/27643.
-    if [[ ${action} == "get" && $(pwd) == "${REPO_ROOT_DIR}" ]]; then
-      local temp_dir="$(mktemp -d)"
-      # Swallow the output as we are returning the stdout in the end.
-      pushd "${temp_dir}" > /dev/null 2>&1
-      GOFLAGS="" go ${action} "$1" || install_failed=1
-      popd > /dev/null 2>&1
-    else
-      GOFLAGS="" go ${action} "$1" || install_failed=1
+  local run=$1
+
+  if [[ "$(basename $1)" != "$2" ]]; then
+    echo "Assuming tool is in package $2"
+    run="${run}/$2"
+  fi
+
+  if [[ -z "$(go list -mod=readonly -f '{{.Module.Version}}' $1)" ]]; then
+    echo "Tool $1/$2 is not included in hack/tools.go, falling back to non-hermetic install (via GOPATH)."
+    if [[ -z "$(which ${tool})" ]]; then
+      local action=get
+      [[ $1 =~ ^[\./].* ]] && action=install
+      # Avoid running `go get` from root dir of the repository, as it can change go.sum and go.mod files.
+      # See discussions in https://github.com/golang/go/issues/27643.
+      if [[ ${action} == "get" && $(pwd) == "${REPO_ROOT_DIR}" ]]; then
+        local temp_dir="$(mktemp -d)"
+        # Swallow the output as we are returning the stdout in the end.
+        pushd "${temp_dir}" > /dev/null 2>&1
+        GOFLAGS="" go ${action} "$1" || install_failed=1
+        popd > /dev/null 2>&1
+      else
+        GOFLAGS="" go ${action} "$1" || install_failed=1
+      fi
     fi
+    (( install_failed )) && return ${install_failed}
+    shift 2
+    ${tool} "$@"
+  else
+    shift 2
+    GOFLAGS="-mod=vendor" go run "${run}" "$@"
   fi
-  (( install_failed )) && return ${install_failed}
-  shift 2
-  ${tool} "$@"
 }
 
 # Add function call to trap

vendor/knative.dev/pkg/network/handlers/drain.go

@@ -47,7 +47,8 @@ var newTimer = func(d time.Duration) timer {
 }
 
 // Drainer wraps an inner http.Handler to support responding to kubelet
-// probes and KProbes with a "200 OK" until the handler is told to Drain.
+// probes and KProbes with a "200 OK" until the handler is told to Drain,
+// or Drainer will optionally run the HealthCheck if it is defined.
 // When the Drainer is told to Drain, it will immediately start to fail
 // probes with a "500 shutting down", and the call will block until no
 // requests have been received for QuietPeriod (defaults to
@@ -56,6 +57,10 @@ type Drainer struct {
 	// Mutex guards the initialization and resets of the timer
 	sync.RWMutex
 
+	// HealthCheck is an optional health check that is performed until the drain signal is received.
+	// When unspecified, a "200 OK" is returned, otherwise this function is invoked.
+	HealthCheck http.HandlerFunc
+
 	// Inner is the http.Handler to which we delegate actual requests.
 	Inner http.Handler
 
@@ -78,6 +83,8 @@ func (d *Drainer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if network.IsKubeletProbe(r) { // Respond to probes regardless of path.
 		if d.draining() {
 			http.Error(w, "shutting down", http.StatusServiceUnavailable)
+		} else if d.HealthCheck != nil {
+			d.HealthCheck(w, r)
 		} else {
 			w.WriteHeader(http.StatusOK)
 		}

vendor/modules.txt

@@ -984,11 +984,11 @@ knative.dev/caching/pkg/client/injection/informers/caching/v1alpha1/image/fake
 knative.dev/caching/pkg/client/injection/informers/factory
 knative.dev/caching/pkg/client/injection/informers/factory/fake
 knative.dev/caching/pkg/client/listers/caching/v1alpha1
-# knative.dev/hack v0.0.0-20201214230143-4ed1ecb8db24
+# knative.dev/hack v0.0.0-20210108203236-ea9c9a0cac5c
 ## explicit
 knative.dev/hack
 knative.dev/hack/shell
-# knative.dev/networking v0.0.0-20210107024535-ecb89ced52d9
+# knative.dev/networking v0.0.0-20210111171437-c30dc94f1dcf
 ## explicit
 knative.dev/networking/config
 knative.dev/networking/pkg
@@ -1022,7 +1022,7 @@ knative.dev/networking/test/conformance/ingress
 knative.dev/networking/test/defaultsystem
 knative.dev/networking/test/test_images/grpc-ping/proto
 knative.dev/networking/test/types
-# knative.dev/pkg v0.0.0-20210107022335-51c72e24c179
+# knative.dev/pkg v0.0.0-20210107211936-93874f0ea7c0
 ## explicit
 knative.dev/pkg/apiextensions/storageversion
 knative.dev/pkg/apiextensions/storageversion/cmd/migrate