Merge pull request #70 from digitalocean/http-transport-option

kube: allow wrapping the underlying http.RoundTripper

kube/objects.go

@@ -182,6 +182,10 @@ func NewClient(opts ...Option) (*Client, error) {
 		return nil, err
 	}
 	config.Timeout = defOpts.timeout
+	if defOpts.transportWrapper != nil {
+		config.Wrap(defOpts.transportWrapper)
+	}
+
 	client, err := kubernetes.NewForConfig(config)
 	if err != nil {
 		return nil, err

kube/objects_test.go

@@ -19,6 +19,7 @@ package kube
 import (
 	"context"
 	"errors"
+	"net/http"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -70,3 +71,37 @@ func TestNewClientErrors(t *testing.T) {
 		assert.Equal(t, errors.New("cannot specify yaml and kubeconfig file paths"), err)
 	})
 }
+
+type failTransport struct{}
+
+func (failTransport) RoundTrip(_ *http.Request) (*http.Response, error) {
+	return nil, errors.New("fail")
+}
+
+func TestNewClientRoundTripper(t *testing.T) {
+	client, err := NewClient(WithTransportWrapper(func(_ http.RoundTripper) http.RoundTripper {
+		return failTransport{}
+	}), WithYaml([]byte(`apiVersion: v1
+kind: Config
+clusters:
+- cluster:
+    server: http://localhost
+  name: cool
+contexts:
+- context:
+    cluster: cool
+    user: admin
+  name: cool
+current-context: cool
+users:
+- name: admin
+`)))
+	assert.NoError(t, err)
+	_, err = client.KubeClient.CoreV1().Namespaces().Create(&corev1.Namespace{
+		TypeMeta: metav1.TypeMeta{Kind: "Namespace", APIVersion: "v1"},
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "kube-system",
+		},
+	})
+	assert.Contains(t, err.Error(), "fail")
+}

kube/options.go

@@ -18,16 +18,18 @@ package kube
 
 import (
 	"errors"
+	"net/http"
 	"time"
 )
 
 const delimiter = ":"
 
 type options struct {
-	paths       []string
-	kubeContext string
-	yaml        []byte
-	timeout     time.Duration
+	paths            []string
+	kubeContext      string
+	yaml             []byte
+	transportWrapper TransportWrapper
+	timeout          time.Duration
 }
 
 // Option function that allows injecting options while building kube.Client.
@@ -73,6 +75,17 @@ func WithTimeout(t time.Duration) Option {
 	}
 }
 
+// TransportWrapper wraps an http.RoundTripper
+type TransportWrapper = func(http.RoundTripper) http.RoundTripper
+
+// WithTransportWrapper allows wrapping the underlying http.RoundTripper
+func WithTransportWrapper(f TransportWrapper) Option {
+	return func(o *options) error {
+		o.transportWrapper = f
+		return nil
+	}
+}
+
 func (o *options) validate() error {
 	if o.yaml != nil && len(o.paths) != 0 {
 		return errors.New("cannot specify yaml and kubeconfig file paths")