Apply namespaceless objects to default namespace

In some not-so-well-defined cases, applying an object to the default namespace
can fail when its yaml doesn't explicitly specify the namespace. The simplest
way to overcome this is to separate them out and pass the namespace flag to
kubectl.

cluster/kubernetes/kubernetes.go

@@ -3,7 +3,6 @@ package kubernetes
 import (
 	"bytes"
 	"fmt"
-	"io"
 	"sync"
 
 	k8syaml "github.com/ghodss/yaml"
@@ -46,10 +45,15 @@ type apiObject struct {
 	bytes    []byte
 	Kind     string `yaml:"kind"`
 	Metadata struct {
-		Name string `yaml:"name"`
+		Name      string `yaml:"name"`
+		Namespace string `yaml:"namespace"`
 	} `yaml:"metadata"`
 }
 
+func (o *apiObject) hasNamespace() bool {
+	return o.Metadata.Namespace != ""
+}
+
 // --- add-ons
 
 // Kubernetes has a mechanism of "Add-ons", whereby manifest files
@@ -82,8 +86,7 @@ func isAddon(obj namespacedLabeled) bool {
 // --- /add ons
 
 type Applier interface {
-	doCommand(log.Logger, string, io.Reader) error
-	stage(string, string, *apiObject)
+	stage(id, cmd string, obj *apiObject)
 	execute(log.Logger, cluster.SyncError)
 }
 

cluster/kubernetes/kubernetes_test.go

@@ -4,7 +4,6 @@ package kubernetes
 // adequate. Starting with Sync.
 
 import (
-	"io"
 	"testing"
 
 	"github.com/go-kit/kit/log"
@@ -14,30 +13,14 @@ import (
 
 type mockApplier struct {
 	commandRun bool
-	applyErr   error
-	deleteErr  error
 
 	changeSet
 }
 
-func (m *mockApplier) doCommand(_ log.Logger, command string, _ io.Reader) error {
-	m.commandRun = true
-	switch command {
-	case "apply":
-		return m.applyErr
-	case "delete":
-		return m.deleteErr
-	default:
-		return nil
-	}
-}
-
-func (m *mockApplier) execute(_ log.Logger, errs cluster.SyncError) {
+func (m *mockApplier) execute(_ log.Logger, _ cluster.SyncError) {
 	for _, cmd := range cmds {
-		if len(m.objs[cmd]) > 0 {
-			if err := m.doCommand(nil, cmd, nil); err != nil {
-				errs[cmd] = err
-			}
+		if len(m.objs[cmd]) != 0 {
+			m.commandRun = true
 		}
 	}
 }

cluster/kubernetes/release.go

@@ -62,25 +62,30 @@ func (c *Kubectl) execute(logger log.Logger, errs cluster.SyncError) {
 	defer c.changeSet.clear()
 
 	for _, cmd := range cmds {
-		buf := &bytes.Buffer{}
-		for _, obj := range c.objs[cmd] {
-			fmt.Fprintln(buf, "---")
-			fmt.Fprintln(buf, string(obj.bytes))
-		}
+		noNsObjs := c.noNsObjs[cmd]
+		nsObjs := c.nsObjs[cmd]
 
-		if err := c.doCommand(logger, cmd, buf); err != nil {
-			for _, obj := range c.objs[cmd] {
+		if err := c.doCommand(logger, makeMultidoc(noNsObjs), cmd, "--namespace", "default"); err != nil {
+			for _, obj := range noNsObjs {
 				r := bytes.NewReader(obj.bytes)
-				if err := c.doCommand(logger, cmd, r); err != nil {
-					errs[obj.Metadata.Name] = err
+				if err := c.doCommand(logger, r, cmd, "--namespace", "default"); err != nil {
+					errs[obj.id] = err
+				}
+			}
+		}
+		if err := c.doCommand(logger, makeMultidoc(nsObjs), cmd); err != nil {
+			for _, obj := range nsObjs {
+				r := bytes.NewReader(obj.bytes)
+				if err := c.doCommand(logger, r, cmd); err != nil {
+					errs[obj.id] = err
 				}
 			}
 		}
 	}
 }
 
-func (c *Kubectl) doCommand(logger log.Logger, command string, r io.Reader) error {
-	args := []string{command, "-f", "-"}
+func (c *Kubectl) doCommand(logger log.Logger, r io.Reader, args ...string) error {
+	args = append(args, "-f", "-")
 	cmd := c.kubectlCommand(args...)
 	cmd.Stdin = r
 	stderr := &bytes.Buffer{}
@@ -98,29 +103,46 @@ func (c *Kubectl) doCommand(logger log.Logger, command string, r io.Reader) erro
 	return err
 }
 
+func makeMultidoc(objs []obj) *bytes.Buffer {
+	buf := &bytes.Buffer{}
+	for _, obj := range objs {
+		fmt.Fprintln(buf, "---")
+		fmt.Fprintln(buf, obj.bytes)
+	}
+	return buf
+}
+
 func (c *Kubectl) kubectlCommand(args ...string) *exec.Cmd {
 	return exec.Command(c.exe, append(c.connectArgs(), args...)...)
 }
 
 type changeSet struct {
-	objs map[string][]obj
+	nsObjs   map[string][]obj
+	noNsObjs map[string][]obj
+}
+
+func (c *changeSet) init() {
+	if c.nsObjs == nil {
+		c.nsObjs = make(map[string][]obj)
+	}
+	if c.noNsObjs == nil {
+		c.noNsObjs = make(map[string][]obj)
+	}
 }
 
 func (c *changeSet) stage(cmd, id string, o *apiObject) {
-	if c.objs == nil {
-		c.objs = make(map[string][]obj)
+	c.init()
+	if o.hasNamespace() {
+		c.nsObjs[cmd] = append(c.nsObjs[cmd], obj{id, o})
+	} else {
+		c.noNsObjs[cmd] = append(c.noNsObjs[cmd], obj{id, o})
 	}
-	c.objs[cmd] = append(c.objs[cmd], obj{id, o})
 }
 
 func (c *changeSet) clear() {
-	if c.objs == nil {
-		c.objs = make(map[string][]obj)
-		return
-	}
-	for cmd := range c.objs {
-		c.objs[cmd] = nil
-	}
+	c.nsObjs = nil
+	c.noNsObjs = nil
+	c.init()
 }
 
 type obj struct {