Merge pull request #60012 from atlassian/dial-with-context

Automatic merge from submit-queue (batch tested with PRs 60012, 63692, 63977, 63960, 64008). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Use Dial with context

**What this PR does / why we need it**:
`net/http/Transport.Dial` field is deprecated:
```go
// DialContext specifies the dial function for creating unencrypted TCP connections.
// If DialContext is nil (and the deprecated Dial below is also nil),
// then the transport dials using package net.
DialContext func(ctx context.Context, network, addr string) (net.Conn, error)

// Dial specifies the dial function for creating unencrypted TCP connections.
//
// Deprecated: Use DialContext instead, which allows the transport
// to cancel dials as soon as they are no longer needed.
// If both are set, DialContext takes priority.
Dial func(network, addr string) (net.Conn, error)
```
This PR switches all `Dial` usages to `DialContext`. Fixes #63455.

**Special notes for your reviewer**:
Also related: kubernetes/kubernetes#59287 kubernetes/kubernetes#58532 kubernetes/kubernetes#815 kubernetes/community#1166 kubernetes/kubernetes#58677 kubernetes/kubernetes#57932

**Release note**:
```release-note
HTTP transport now uses `context.Context` to cancel dial operations. k8s.io/client-go/transport/Config struct has been updated to accept a function with a `context.Context` parameter. This is a breaking change if you use this field in your code.
```
/sig api-machinery
/kind enhancement
/cc @sttts

Kubernetes-commit: ddf551c24b7d88454f8332ce6855e53281440958

discovery/discovery_client.go

@@ -44,12 +44,8 @@ const (
 	defaultRetries = 2
 	// protobuf mime type
 	mimePb = "application/com.github.proto-openapi.spec.v2@v1.0+protobuf"
-)
-
-var (
 	// defaultTimeout is the maximum amount of time per request when no timeout has been set on a RESTClient.
 	// Defaults to 32s in order to have a distinguishable length of time, relative to other timeouts that exist.
-	// It's a variable to be able to change it in tests.
 	defaultTimeout = 32 * time.Second
 )
 

discovery/discovery_client_test.go

@@ -23,12 +23,11 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"reflect"
-	"strings"
 	"testing"
-	"time"
 
 	"github.com/gogo/protobuf/proto"
 	"github.com/googleapis/gnostic/OpenAPIv2"
+	"github.com/stretchr/testify/assert"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
@@ -131,31 +130,11 @@ func TestGetServerGroupsWithBrokenServer(t *testing.T) {
 		}
 	}
 }
-func TestGetServerGroupsWithTimeout(t *testing.T) {
-	done := make(chan bool)
-	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
-		// first we need to write headers, otherwise http client will complain about
-		// exceeding timeout awaiting headers, only after we can block the call
-		w.Header().Set("Connection", "keep-alive")
-		if wf, ok := w.(http.Flusher); ok {
-			wf.Flush()
-		}
-		<-done
-	}))
-	defer server.Close()
-	defer close(done)
-	client := NewDiscoveryClientForConfigOrDie(&restclient.Config{Host: server.URL, Timeout: 2 * time.Second})
-	_, err := client.ServerGroups()
-	// the error we're getting here is wrapped in errors.errorString which makes
-	// it impossible to unwrap and check it's attributes, so instead we're checking
-	// the textual output which is presenting http.httpError with timeout set to true
-	if err == nil {
-		t.Fatal("missing error")
-	}
-	if !strings.Contains(err.Error(), "timeout:true") &&
-		!strings.Contains(err.Error(), "context.deadlineExceededError") {
-		t.Fatalf("unexpected error: %v", err)
-	}
+
+func TestTimeoutIsSet(t *testing.T) {
+	cfg := &restclient.Config{}
+	setDiscoveryDefaults(cfg)
+	assert.Equal(t, defaultTimeout, cfg.Timeout)
 }
 
 func TestGetServerResourcesWithV1Server(t *testing.T) {

rest/config.go

@@ -17,6 +17,7 @@ limitations under the License.
 package rest
 
 import (
+	"context"
 	"fmt"
 	"io/ioutil"
 	"net"
@@ -110,7 +111,7 @@ type Config struct {
 	Timeout time.Duration
 
 	// Dial specifies the dial function for creating unencrypted TCP connections.
-	Dial func(network, addr string) (net.Conn, error)
+	Dial func(ctx context.Context, network, address string) (net.Conn, error)
 
 	// Version forces a specific version to be used (if registered)
 	// Do we need this?