From 3bc99d57e664c287a41b91719a6100b74f2a8bb7 Mon Sep 17 00:00:00 2001
From: Sam Broughton <sam@weave.works>
Date: Sun, 17 Dec 2017 14:33:30 +0200
Subject: [PATCH] Store staged objects in a slice rather than a map

This brings back the previous ordering without doing a sort. Since we no longer
apply objects one at a time, we don't need an id.
---
 cluster/kubernetes/kubernetes.go      |  8 ++--
 cluster/kubernetes/kubernetes_test.go | 14 +++----
 cluster/kubernetes/release.go         | 57 +++++++++++++++------------
 3 files changed, 42 insertions(+), 37 deletions(-)

diff --git a/cluster/kubernetes/kubernetes.go b/cluster/kubernetes/kubernetes.go
index 60c655d3dc..69ae9738f8 100644
--- a/cluster/kubernetes/kubernetes.go
+++ b/cluster/kubernetes/kubernetes.go
@@ -83,8 +83,8 @@ func isAddon(obj namespacedLabeled) bool {
 type Applier interface {
 	delete(log.Logger, []byte) error
 	apply(log.Logger, []byte) error
-	stageDelete(string, *apiObject)
-	stageApply(string, *apiObject)
+	stageDelete(*apiObject)
+	stageApply(*apiObject)
 	execute(log.Logger, cluster.SyncError) error
 }
 
@@ -199,7 +199,7 @@ func (c *Cluster) Sync(spec cluster.SyncDef) error {
 		if len(action.Delete) > 0 {
 			obj, err := definitionObj(action.Delete)
 			if err == nil {
-				c.applier.stageDelete(action.ResourceID, obj)
+				c.applier.stageDelete(obj)
 			} else {
 				errs[action.ResourceID] = err
 				continue
@@ -208,7 +208,7 @@ func (c *Cluster) Sync(spec cluster.SyncDef) error {
 		if len(action.Apply) > 0 {
 			obj, err := definitionObj(action.Apply)
 			if err == nil {
-				c.applier.stageApply(action.ResourceID, obj)
+				c.applier.stageApply(obj)
 			} else {
 				errs[action.ResourceID] = err
 				continue
diff --git a/cluster/kubernetes/kubernetes_test.go b/cluster/kubernetes/kubernetes_test.go
index da83ae821d..d369ff23fd 100644
--- a/cluster/kubernetes/kubernetes_test.go
+++ b/cluster/kubernetes/kubernetes_test.go
@@ -182,7 +182,7 @@ type mockApplier struct {
 	createErr error
 	deleteErr error
 
-	*changeSet
+	changeSet
 }
 
 func (m *mockApplier) apply(_ log.Logger, _ []byte) error {
@@ -196,14 +196,14 @@ func (m *mockApplier) delete(_ log.Logger, _ []byte) error {
 }
 
 func (m *mockApplier) execute(_ log.Logger, errs cluster.SyncError) error {
-	for id, _ := range m.deleteObjs {
+	if len(m.deleteObjs) > 0 {
 		if err := m.delete(nil, nil); err != nil {
-			errs[id] = err
+			return err
 		}
 	}
-	for id, _ := range m.applyObjs {
+	if len(m.applyObjs) > 0 {
 		if err := m.apply(nil, nil); err != nil {
-			errs[id] = err
+			return err
 		}
 	}
 	if len(errs) != 0 {
@@ -223,9 +223,7 @@ metadata:
 
 func setup(t *testing.T) (*Cluster, *mockApplier) {
 	clientset := &mockClientset{}
-	applier := &mockApplier{
-		changeSet: newChangeSet(),
-	}
+	applier := &mockApplier{}
 	kube, err := NewCluster(clientset, applier, nil, log.NewNopLogger())
 	if err != nil {
 		t.Fatal(err)
diff --git a/cluster/kubernetes/release.go b/cluster/kubernetes/release.go
index 71520b72e2..82ab3577f3 100644
--- a/cluster/kubernetes/release.go
+++ b/cluster/kubernetes/release.go
@@ -17,14 +17,13 @@ type Kubectl struct {
 	exe    string
 	config *rest.Config
 
-	*changeSet
+	changeSet
 }
 
 func NewKubectl(exe string, config *rest.Config) *Kubectl {
 	return &Kubectl{
-		exe:       exe,
-		config:    config,
-		changeSet: newChangeSet(),
+		exe:    exe,
+		config: config,
 	}
 }
 
@@ -55,19 +54,28 @@ func (c *Kubectl) connectArgs() []string {
 }
 
 func (c *Kubectl) execute(logger log.Logger, errs cluster.SyncError) error {
-	for id, obj := range c.deleteObjs {
-		logger := log.With(logger, "resource", id)
-		if err := c.delete(logger, obj.bytes); err != nil {
-			errs[id] = err
-		}
+	defer c.changeSet.clear()
+
+	var deleteBuf bytes.Buffer
+	for _, obj := range c.deleteObjs {
+		fmt.Fprintln(&deleteBuf, "---")
+		fmt.Fprintln(&deleteBuf, string(obj.bytes))
 	}
-	for id, obj := range c.applyObjs {
-		logger := log.With(logger, "resource", id)
-		if err := c.apply(logger, obj.bytes); err != nil {
-			errs[id] = err
-		}
+
+	if err := c.delete(logger, deleteBuf.Bytes()); err != nil {
+		errs["deleting"] = err
 	}
-	c.changeSet = newChangeSet()
+
+	var applyBuf bytes.Buffer
+	for _, obj := range c.applyObjs {
+		fmt.Fprintln(&applyBuf, "---")
+		fmt.Fprintln(&applyBuf, string(obj.bytes))
+	}
+
+	if err := c.apply(logger, applyBuf.Bytes()); err != nil {
+		errs["applying"] = err
+	}
+
 	if len(errs) != 0 {
 		return errs
 	}
@@ -105,19 +113,18 @@ func (c *Kubectl) kubectlCommand(args ...string) *exec.Cmd {
 }
 
 type changeSet struct {
-	deleteObjs, applyObjs map[string]*apiObject
+	deleteObjs, applyObjs []*apiObject
 }
 
-func newChangeSet() *changeSet {
-	return &changeSet{
-		deleteObjs: make(map[string]*apiObject),
-		applyObjs:  make(map[string]*apiObject),
-	}
+func (c *changeSet) stageDelete(obj *apiObject) {
+	c.deleteObjs = append(c.deleteObjs, obj)
 }
-func (c *changeSet) stageDelete(id string, obj *apiObject) {
-	c.deleteObjs[id] = obj
+
+func (c *changeSet) stageApply(obj *apiObject) {
+	c.applyObjs = append(c.applyObjs, obj)
 }
 
-func (c *changeSet) stageApply(id string, obj *apiObject) {
-	c.applyObjs[id] = obj
+func (c *changeSet) clear() {
+	c.deleteObjs = nil
+	c.applyObjs = nil
 }