refactor: reduce usage of k8s.io/kubernetes packages (#258)

Signed-off-by: Mikhail Mazurskiy <mmazurskiy@gitlab.com>

go.mod

@@ -3,6 +3,7 @@ module github.com/argoproj/gitops-engine
 go 1.15
 
 require (
+	github.com/davecgh/go-spew v1.1.1
 	github.com/evanphx/json-patch v4.9.0+incompatible
 	github.com/go-logr/logr v0.3.0
 	github.com/golang/mock v1.4.4

internal/kubernetes_vendor/pkg/api/v1/endpoints/util.go

@@ -0,0 +1,90 @@
+/*
+Copyright 2015 The Kubernetes Authors.
+
+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 endpoints
+
+import (
+	"bytes"
+	"crypto/md5"
+	"hash"
+	"sort"
+
+	hashutil "github.com/argoproj/gitops-engine/internal/kubernetes_vendor/pkg/util/hash"
+	v1 "k8s.io/api/core/v1"
+)
+
+// LessEndpointAddress compares IP addresses lexicographically and returns true if first argument is lesser than second
+func LessEndpointAddress(a, b *v1.EndpointAddress) bool {
+	ipComparison := bytes.Compare([]byte(a.IP), []byte(b.IP))
+	if ipComparison != 0 {
+		return ipComparison < 0
+	}
+	if b.TargetRef == nil {
+		return false
+	}
+	if a.TargetRef == nil {
+		return true
+	}
+	return a.TargetRef.UID < b.TargetRef.UID
+}
+
+// SortSubsets sorts an array of EndpointSubset objects in place.  For ease of
+// use it returns the input slice.
+func SortSubsets(subsets []v1.EndpointSubset) []v1.EndpointSubset {
+	for i := range subsets {
+		ss := &subsets[i]
+		sort.Sort(addrsByIPAndUID(ss.Addresses))
+		sort.Sort(addrsByIPAndUID(ss.NotReadyAddresses))
+		sort.Sort(portsByHash(ss.Ports))
+	}
+	sort.Sort(subsetsByHash(subsets))
+	return subsets
+}
+
+func hashObject(hasher hash.Hash, obj interface{}) []byte {
+	hashutil.DeepHashObject(hasher, obj)
+	return hasher.Sum(nil)
+}
+
+type subsetsByHash []v1.EndpointSubset
+
+func (sl subsetsByHash) Len() int      { return len(sl) }
+func (sl subsetsByHash) Swap(i, j int) { sl[i], sl[j] = sl[j], sl[i] }
+func (sl subsetsByHash) Less(i, j int) bool {
+	hasher := md5.New()
+	h1 := hashObject(hasher, sl[i])
+	h2 := hashObject(hasher, sl[j])
+	return bytes.Compare(h1, h2) < 0
+}
+
+type addrsByIPAndUID []v1.EndpointAddress
+
+func (sl addrsByIPAndUID) Len() int      { return len(sl) }
+func (sl addrsByIPAndUID) Swap(i, j int) { sl[i], sl[j] = sl[j], sl[i] }
+func (sl addrsByIPAndUID) Less(i, j int) bool {
+	return LessEndpointAddress(&sl[i], &sl[j])
+}
+
+type portsByHash []v1.EndpointPort
+
+func (sl portsByHash) Len() int      { return len(sl) }
+func (sl portsByHash) Swap(i, j int) { sl[i], sl[j] = sl[j], sl[i] }
+func (sl portsByHash) Less(i, j int) bool {
+	hasher := md5.New()
+	h1 := hashObject(hasher, sl[i])
+	h2 := hashObject(hasher, sl[j])
+	return bytes.Compare(h1, h2) < 0
+}

internal/kubernetes_vendor/pkg/util/hash/hash.go

@@ -0,0 +1,37 @@
+/*
+Copyright 2015 The Kubernetes Authors.
+
+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 hash
+
+import (
+	"hash"
+
+	"github.com/davecgh/go-spew/spew"
+)
+
+// DeepHashObject writes specified object to hash using the spew library
+// which follows pointers and prints actual values of the nested objects
+// ensuring the hash does not change when a pointer changes.
+func DeepHashObject(hasher hash.Hash, objectToWrite interface{}) {
+	hasher.Reset()
+	printer := spew.ConfigState{
+		Indent:         " ",
+		SortKeys:       true,
+		DisableMethods: true,
+		SpewKeys:       true,
+	}
+	printer.Fprintf(hasher, "%#v", objectToWrite)
+}

pkg/diff/diff.go

@@ -18,8 +18,8 @@ import (
 	"k8s.io/apimachinery/pkg/util/jsonmergepatch"
 	"k8s.io/apimachinery/pkg/util/strategicpatch"
 	"k8s.io/client-go/kubernetes/scheme"
-	"k8s.io/kubernetes/pkg/api/v1/endpoints"
 
+	"github.com/argoproj/gitops-engine/internal/kubernetes_vendor/pkg/api/v1/endpoints"
 	jsonutil "github.com/argoproj/gitops-engine/pkg/utils/json"
 	kubescheme "github.com/argoproj/gitops-engine/pkg/utils/kube/scheme"
 )

pkg/health/health_pod.go

@@ -8,7 +8,7 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
-	podutil "k8s.io/kubernetes/pkg/api/v1/pod"
+	"k8s.io/kubectl/pkg/util/podutils"
 )
 
 func getPodHealth(obj *unstructured.Unstructured) (*HealthStatus, error) {
@@ -96,7 +96,7 @@ func getCorev1PodHealth(pod *corev1.Pod) (*HealthStatus, error) {
 		switch pod.Spec.RestartPolicy {
 		case corev1.RestartPolicyAlways:
 			// if pod is ready, it is automatically healthy
-			if podutil.IsPodReady(pod) {
+			if podutils.IsPodReady(pod) {
 				return &HealthStatus{
 					Status:  HealthStatusHealthy,
 					Message: pod.Status.Message,