Add --plugins flag to velero install (#1930)

* Add plugins flag to install

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

pkg/builder/container_builder.go

@@ -17,6 +17,8 @@ limitations under the License.
 package builder
 
 import (
+	"strings"
+
 	corev1api "k8s.io/api/core/v1"
 )
 
@@ -35,6 +37,32 @@ func ForContainer(name, image string) *ContainerBuilder {
 	}
 }
 
+// ForPluginContainer is a helper builder specifically for plugin init containers
+func ForPluginContainer(image string, pullPolicy corev1api.PullPolicy) *ContainerBuilder {
+	volumeMount := ForVolumeMount("plugins", "/target").Result()
+	return ForContainer(getName(image), image).PullPolicy(pullPolicy).VolumeMounts(volumeMount)
+}
+
+// getName returns the 'name' component of a docker
+// image (i.e. everything after the last '/' and before
+// any subsequent ':')
+func getName(image string) string {
+	slashIndex := strings.LastIndex(image, "/")
+	colonIndex := strings.LastIndex(image, ":")
+
+	start := 0
+	if slashIndex > 0 {
+		start = slashIndex + 1
+	}
+
+	end := len(image)
+	if colonIndex > slashIndex {
+		end = colonIndex
+	}
+
+	return image[start:end]
+}
+
 // Result returns the built Container.
 func (b *ContainerBuilder) Result() *corev1api.Container {
 	return b.object
@@ -66,3 +94,8 @@ func (b *ContainerBuilder) Env(vars ...*corev1api.EnvVar) *ContainerBuilder {
 	}
 	return b
 }
+
+func (b *ContainerBuilder) PullPolicy(pullPolicy corev1api.PullPolicy) *ContainerBuilder {
+	b.object.ImagePullPolicy = pullPolicy
+	return b
+}

pkg/builder/container_builder_test.go

@@ -0,0 +1,62 @@
+/*
+Copyright 2018, 2019 the Velero contributors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package builder
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetName(t *testing.T) {
+	tests := []struct {
+		name     string
+		image    string
+		expected string
+	}{
+		{
+			name:     "image name with registry hostname and tag",
+			image:    "gcr.io/my-repo/my-image:latest",
+			expected: "my-image",
+		},
+		{
+			name:     "image name with registry hostname, without tag",
+			image:    "gcr.io/my-repo/my-image",
+			expected: "my-image",
+		},
+		{
+			name:     "image name without registry hostname, with tag",
+			image:    "my-repo/my-image:latest",
+			expected: "my-image",
+		},
+		{
+			name:     "image name without registry hostname, without tag",
+			image:    "my-repo/my-image",
+			expected: "my-image",
+		},
+		{
+			name:     "image name with registry hostname and port, and tag",
+			image:    "mycustomregistry.io:8080/my-repo/my-image:latest",
+			expected: "my-image",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			assert.Equal(t, test.expected, getName(test.image))
+		})
+	}
+}