Custom improvements for OpenShift (#825)

* Custom improvements for OpenShift

Signed-off-by: Matej Vasek <mvasek@redhat.com>

* fixup: osh cred loader

Signed-off-by: Matej Vasek <mvasek@redhat.com>

* fixup: style

Signed-off-by: Matej Vasek <mvasek@redhat.com>

* fixup: dns-err detec for fallback in cluster dial

Signed-off-by: Matej Vasek <mvasek@redhat.com>

cmd/build.go

@@ -53,7 +53,7 @@ kn func build --builder cnbs/sample-builder:bionic
 	cmd.Flags().StringP("builder", "b", "", "Buildpack builder, either an as a an image name or a mapping name.\nSpecified value is stored in func.yaml for subsequent builds.")
 	cmd.Flags().BoolP("confirm", "c", false, "Prompt to confirm all configuration options (Env: $FUNC_CONFIRM)")
 	cmd.Flags().StringP("image", "i", "", "Full image name in the form [registry]/[namespace]/[name]:[tag] (optional). This option takes precedence over --registry (Env: $FUNC_IMAGE)")
-	cmd.Flags().StringP("registry", "r", "", "Registry + namespace part of the image to build, ex 'quay.io/myuser'.  The full image name is automatically determined based on the local directory name. If not provided the registry will be taken from func.yaml (Env: $FUNC_REGISTRY)")
+	cmd.Flags().StringP("registry", "r", GetDefaultRegistry(), "Registry + namespace part of the image to build, ex 'quay.io/myuser'.  The full image name is automatically determined based on the local directory name. If not provided the registry will be taken from func.yaml (Env: $FUNC_REGISTRY)")
 	cmd.Flags().BoolP("push", "u", false, "Attempt to push the function image after being successfully built")
 	setPathFlag(cmd)
 

cmd/client.go

@@ -1,13 +1,13 @@
 package cmd
 
 import (
-	"net/http"
-
 	fn "knative.dev/kn-plugin-func"
 	"knative.dev/kn-plugin-func/buildpacks"
 	"knative.dev/kn-plugin-func/docker"
 	"knative.dev/kn-plugin-func/docker/creds"
+	fnhttp "knative.dev/kn-plugin-func/http"
 	"knative.dev/kn-plugin-func/knative"
+	"knative.dev/kn-plugin-func/openshift"
 	"knative.dev/kn-plugin-func/pipelines/tekton"
 	"knative.dev/kn-plugin-func/progress"
 )
@@ -22,8 +22,36 @@ type ClientOptions struct {
 
 type ClientFactory func(opts ClientOptions) *fn.Client
 
-func NewClientFactory(transport http.RoundTripper) ClientFactory {
-	return func(clientOptions ClientOptions) *fn.Client {
+// NewDefaultClientFactory returns a function that creates instances of function.Client and a cleanup routine.
+//
+// This function may allocate resources that are used by produced instances of function.Client.
+//
+// To free these resources (after instances of function.Client are no longer in use)
+// caller of this function has to invoke the cleanup routine.
+//
+// Usage:
+//   newClient, cleanUp := NewDefaultClientFactory()
+//   defer cleanUp()
+//   fnClient := newClient()
+//   // use your fnClient here...
+func NewDefaultClientFactory() (newClient ClientFactory, cleanUp func() error) {
+
+	var transportOpts []fnhttp.Option
+	var additionalCredLoaders []creds.CredentialsCallback
+
+	switch {
+	case openshift.IsOpenShift():
+		transportOpts = append(transportOpts, openshift.WithOpenShiftServiceCA())
+		additionalCredLoaders = openshift.GetDockerCredentialLoaders()
+	default:
+	}
+
+	transport := fnhttp.NewRoundTripper(transportOpts...)
+	cleanUp = func() error {
+		return transport.Close()
+	}
+
+	newClient = func(clientOptions ClientOptions) *fn.Client {
 		builder := buildpacks.NewBuilder()
 		builder.Verbose = clientOptions.Verbose
 
@@ -33,7 +61,8 @@ func NewClientFactory(transport http.RoundTripper) ClientFactory {
 		credentialsProvider := creds.NewCredentialsProvider(
 			creds.WithPromptForCredentials(newPromptForCredentials()),
 			creds.WithPromptForCredentialStore(newPromptForCredentialStore()),
-			creds.WithTransport(transport))
+			creds.WithTransport(transport),
+			creds.WithAdditionalCredentialLoaders(additionalCredLoaders...))
 
 		pusher := docker.NewPusher(
 			docker.WithCredentialsProvider(credentialsProvider),
@@ -84,4 +113,15 @@ func NewClientFactory(transport http.RoundTripper) ClientFactory {
 
 		return fn.New(opts...)
 	}
+
+	return newClient, cleanUp
+}
+
+func GetDefaultRegistry() string {
+	switch {
+	case openshift.IsOpenShift():
+		return openshift.GetDefaultRegistry()
+	default:
+		return ""
+	}
 }

cmd/deploy.go

@@ -59,7 +59,7 @@ kn func deploy --image quay.io/myuser/myfunc -n myns
 		"You may provide this flag multiple times for setting multiple environment variables. "+
 		"To unset, specify the environment variable name followed by a \"-\" (e.g., NAME-).")
 	cmd.Flags().StringP("image", "i", "", "Full image name in the form [registry]/[namespace]/[name]:[tag] (optional). This option takes precedence over --registry (Env: $FUNC_IMAGE)")
-	cmd.Flags().StringP("registry", "r", "", "Registry + namespace part of the image to build, ex 'quay.io/myuser'.  The full image name is automatically determined based on the local directory name. If not provided the registry will be taken from func.yaml (Env: $FUNC_REGISTRY)")
+	cmd.Flags().StringP("registry", "r", GetDefaultRegistry(), "Registry + namespace part of the image to build, ex 'quay.io/myuser'.  The full image name is automatically determined based on the local directory name. If not provided the registry will be taken from func.yaml (Env: $FUNC_REGISTRY)")
 	cmd.Flags().StringP("build", "b", fn.DefaultBuildType, fmt.Sprintf("Build specifies the way the function should be built. Supported types are %s (Env: $FUNC_BUILD)", fn.SupportedBuildTypes(true)))
 	cmd.Flags().BoolP("push", "u", true, "Attempt to push the function image to registry before deploying (Env: $FUNC_PUSH)")
 	setPathFlag(cmd)

cmd/root.go

@@ -14,7 +14,6 @@ import (
 	"knative.dev/client/pkg/util"
 
 	fn "knative.dev/kn-plugin-func"
-	fnhttp "knative.dev/kn-plugin-func/http"
 )
 
 var exampleTemplate = template.Must(template.New("example").Parse(`
@@ -90,11 +89,11 @@ Create, build and deploy Functions in serverless containers for multiple runtime
 	newClient := config.NewClient
 
 	if newClient == nil {
-		transport := fnhttp.NewRoundTripper()
-		root.PostRun = func(cmd *cobra.Command, args []string) {
-			transport.Close()
+		var cleanUp func() error
+		newClient, cleanUp = NewDefaultClientFactory()
+		root.PersistentPostRunE = func(cmd *cobra.Command, args []string) error {
+			return cleanUp()
 		}
-		newClient = NewClientFactory(transport)
 	}
 
 	root.AddCommand(NewVersionCmd(version))

http/transport.go

@@ -119,7 +119,7 @@ func (d *dialerWithFallback) DialContext(ctx context.Context, network, address s
 	}
 
 	var dnsErr *net.DNSError
-	if !(errors.As(err, &dnsErr) && dnsErr.IsNotFound) {
+	if !errors.As(err, &dnsErr) {
 		return nil, err
 	}
 

openshift/openshift.go

@@ -0,0 +1,166 @@
+package openshift
+
+import (
+	"context"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"strings"
+	"sync"
+	"time"
+
+	v1 "k8s.io/api/core/v1"
+	k8sErrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/fields"
+	"k8s.io/apimachinery/pkg/util/rand"
+
+	"knative.dev/kn-plugin-func/docker"
+	"knative.dev/kn-plugin-func/docker/creds"
+	fnhttp "knative.dev/kn-plugin-func/http"
+	"knative.dev/kn-plugin-func/k8s"
+)
+
+const (
+	registryHost     = "image-registry.openshift-image-registry.svc"
+	registryHostPort = registryHost + ":5000"
+)
+
+func GetServiceCA(ctx context.Context) (*x509.Certificate, error) {
+	client, ns, err := k8s.NewClientAndResolvedNamespace("")
+	if err != nil {
+		return nil, err
+	}
+
+	cfgMapName := "service-ca-config-" + rand.String(5)
+
+	cfgMap := &v1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:        cfgMapName,
+			Annotations: map[string]string{"service.beta.openshift.io/inject-cabundle": "true"},
+		},
+	}
+
+	configMaps := client.CoreV1().ConfigMaps(ns)
+
+	nameSelector := fields.OneTermEqualSelector("metadata.name", cfgMapName).String()
+	listOpts := metav1.ListOptions{
+		Watch:         true,
+		FieldSelector: nameSelector,
+	}
+
+	watch, err := configMaps.Watch(ctx, listOpts)
+	if err != nil {
+		return nil, err
+	}
+	defer watch.Stop()
+
+	crtChan := make(chan string)
+	go func() {
+		for event := range watch.ResultChan() {
+			cm, ok := event.Object.(*v1.ConfigMap)
+			if !ok {
+				continue
+			}
+			if crt, ok := cm.Data["service-ca.crt"]; ok {
+				crtChan <- crt
+				close(crtChan)
+				break
+			}
+		}
+	}()
+
+	_, err = configMaps.Create(ctx, cfgMap, metav1.CreateOptions{})
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		_ = configMaps.Delete(ctx, cfgMapName, metav1.DeleteOptions{})
+	}()
+
+	select {
+	case crt := <-crtChan:
+		blk, _ := pem.Decode([]byte(crt))
+		return x509.ParseCertificate(blk.Bytes)
+	case <-time.After(time.Second * 5):
+		return nil, errors.New("failed to get OpenShift's service CA in time")
+	}
+}
+
+// WithOpenShiftServiceCA enables trust to OpenShift's service CA for internal image registry
+func WithOpenShiftServiceCA() fnhttp.Option {
+	var selectCA func(ctx context.Context, serverName string) (*x509.Certificate, error)
+	ca, err := GetServiceCA(context.TODO())
+	if err == nil {
+		selectCA = func(ctx context.Context, serverName string) (*x509.Certificate, error) {
+			if strings.HasPrefix(serverName, registryHost) {
+				return ca, nil
+			}
+			return nil, nil
+		}
+	}
+	return fnhttp.WithSelectCA(selectCA)
+}
+
+func GetDefaultRegistry() string {
+	ns, _ := k8s.GetNamespace("")
+	if ns == "" {
+		ns = "default"
+	}
+
+	return registryHostPort + "/" + ns
+}
+
+func GetDockerCredentialLoaders() []creds.CredentialsCallback {
+	conf := k8s.GetClientConfig()
+
+	rawConf, err := conf.RawConfig()
+	if err != nil {
+		return nil
+	}
+
+	cc := rawConf.Contexts[rawConf.CurrentContext]
+	authInfo := rawConf.AuthInfos[cc.AuthInfo]
+
+	var user string
+	parts := strings.SplitN(cc.AuthInfo, "/", 2)
+	if len(parts) >= 1 {
+		user = parts[0]
+	} else {
+		return nil
+	}
+	credentials := docker.Credentials{
+		Username: user,
+		Password: authInfo.Token,
+	}
+
+	return []creds.CredentialsCallback{
+		func(registry string) (docker.Credentials, error) {
+			if registry == registryHostPort {
+				return credentials, nil
+			}
+			return docker.Credentials{}, nil
+		},
+	}
+
+}
+
+var isOpenShift bool
+var checkOpenShiftOnce sync.Once
+
+func IsOpenShift() bool {
+	checkOpenShiftOnce.Do(func() {
+		client, err := k8s.NewKubernetesClientset()
+		if err != nil {
+			isOpenShift = false
+			return
+		}
+		_, err = client.CoreV1().Services("openshift-image-registry").Get(context.TODO(), "image-registry", metav1.GetOptions{})
+		if k8sErrors.IsNotFound(err) {
+			isOpenShift = false
+			return
+		}
+		isOpenShift = true
+	})
+	return isOpenShift
+}

openshift/openshift_test.go

@@ -0,0 +1,31 @@
+package openshift_test
+
+import (
+	"net/http"
+
+	"testing"
+
+	fnhttp "knative.dev/kn-plugin-func/http"
+	"knative.dev/kn-plugin-func/openshift"
+)
+
+func TestRoundTripper(t *testing.T) {
+	if !openshift.IsOpenShift() {
+		t.Skip("The cluster in not an instance of OpenShift.")
+		return
+	}
+
+	transport := fnhttp.NewRoundTripper(openshift.WithOpenShiftServiceCA())
+	defer transport.Close()
+
+	client := http.Client{
+		Transport: transport,
+	}
+
+	resp, err := client.Get("https://image-registry.openshift-image-registry.svc.cluster.local:5000/v2/")
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	defer resp.Body.Close()
+}