Adding create. (#30)

pkg/commands/commands.go

@@ -23,6 +23,7 @@ import (
 //    https://github.com/google/go-containerregistry/issues/80
 func AddKubeCommands(topLevel *cobra.Command) {
 	addDelete(topLevel)
+	addCreate(topLevel)
 	addApply(topLevel)
 	addResolve(topLevel)
 	addPublish(topLevel)

pkg/commands/create.go

@@ -0,0 +1,137 @@
+// Copyright 2018 Google LLC All Rights Reserved.
+//
+// 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 commands
+
+import (
+	"github.com/google/ko/pkg/commands/options"
+	"k8s.io/kubernetes/pkg/kubectl/genericclioptions"
+	"log"
+	"os"
+	"os/exec"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+)
+
+// addCreate augments our CLI surface with apply.
+func addCreate(topLevel *cobra.Command) {
+	koCreateFlags := []string{}
+	lo := &options.LocalOptions{}
+	no := &options.NameOptions{}
+	fo := &options.FilenameOptions{}
+	ta := &options.TagsOptions{}
+	do := &options.DebugOptions{}
+	create := &cobra.Command{
+		Use:   "create -f FILENAME",
+		Short: "Create the input files with image references resolved to built/pushed image digests.",
+		Long:  `This sub-command finds import path references within the provided files, builds them into Go binaries, containerizes them, publishes them, and then feeds the resulting yaml into "kubectl create".`,
+		Example: `
+  # Build and publish import path references to a Docker
+  # Registry as:
+  #   ${KO_DOCKER_REPO}/<package name>-<hash of import path>
+  # Then, feed the resulting yaml into "kubectl create".
+  # When KO_DOCKER_REPO is ko.local, it is the same as if
+  # --local was passed.
+  ko create -f config/
+
+  # Build and publish import path references to a Docker
+  # Registry preserving import path names as:
+  #   ${KO_DOCKER_REPO}/<import path>
+  # Then, feed the resulting yaml into "kubectl create".
+  ko create --preserve-import-paths -f config/
+
+  # Build and publish import path references to a Docker
+  # daemon as:
+  #   ko.local/<import path>
+  # Then, feed the resulting yaml into "kubectl create".
+  ko create --local -f config/
+
+  # Create from stdin:
+  cat config.yaml | ko create -f -`,
+		Args: cobra.NoArgs,
+		Run: func(cmd *cobra.Command, args []string) {
+			// Create a set of ko-specific flags to ignore when passing through
+			// kubectl global flags.
+			ignoreSet := make(map[string]struct{})
+			for _, s := range koCreateFlags {
+				ignoreSet[s] = struct{}{}
+			}
+
+			// Filter out ko flags from what we will pass through to kubectl.
+			kubectlFlags := []string{}
+			cmd.Flags().Visit(func(flag *pflag.Flag) {
+				if _, ok := ignoreSet[flag.Name]; !ok {
+					kubectlFlags = append(kubectlFlags, "--"+flag.Name, flag.Value.String())
+				}
+			})
+
+			// Issue a "kubectl create" command reading from stdin,
+			// to which we will pipe the resolved files.
+			argv := []string{"create", "-f", "-"}
+			argv = append(argv, kubectlFlags...)
+			kubectlCmd := exec.Command("kubectl", argv...)
+
+			// Pass through our environment
+			kubectlCmd.Env = os.Environ()
+			// Pass through our std{out,err} and make our resolved buffer stdin.
+			kubectlCmd.Stderr = os.Stderr
+			kubectlCmd.Stdout = os.Stdout
+
+			// Wire up kubectl stdin to resolveFilesToWriter.
+			stdin, err := kubectlCmd.StdinPipe()
+			if err != nil {
+				log.Fatalf("error piping to 'kubectl create': %v", err)
+			}
+
+			go func() {
+				// kubectl buffers data before starting to create it, which
+				// can lead to resources being created more slowly than desired.
+				// In the case of --watch, it can lead to resources not being
+				// applied at all until enough iteration has occurred.  To work
+				// around this, we prime the stream with a bunch of empty objects
+				// which kubectl will discard.
+				// See https://github.com/google/go-containerregistry/pull/348
+				for i := 0; i < 1000; i++ {
+					stdin.Write([]byte("---\n"))
+				}
+				// Once primed kick things off.
+				resolveFilesToWriter(fo, no, lo, ta, do, stdin)
+			}()
+
+			// Run it.
+			if err := kubectlCmd.Run(); err != nil {
+				log.Fatalf("error executing 'kubectl create': %v", err)
+			}
+		},
+	}
+	options.AddLocalArg(create, lo)
+	options.AddNamingArgs(create, no)
+	options.AddFileArg(create, fo)
+	options.AddTagsArg(create, ta)
+	options.AddDebugArg(create, do)
+
+	// Collect the ko-specific apply flags before registering the kubectl global
+	// flags so that we can ignore them when passing kubectl global flags through
+	// to kubectl.
+	create.Flags().VisitAll(func(flag *pflag.Flag) {
+		koCreateFlags = append(koCreateFlags, flag.Name)
+	})
+
+	// Register the kubectl global flags.
+	kubeConfigFlags := genericclioptions.NewConfigFlags()
+	kubeConfigFlags.AddFlags(create.Flags())
+
+	topLevel.AddCommand(create)
+}