From 9d9925ec86bb779c60655bbf487d7921f22a36eb Mon Sep 17 00:00:00 2001
From: "Suren A. Chilingaryan" <csa@suren.me>
Date: Mon, 19 Mar 2018 06:21:30 +0100
Subject: Include peer-finder and modify to match also IPs in order to support
 hostNetwork configuration

---
 peer-finder/Dockerfile          |  23 ++++
 peer-finder/Makefile            |  33 +++++
 peer-finder/peer-finder.go      | 152 ++++++++++++++++++++++
 peer-finder/sets/BUILD          |  71 +++++++++++
 peer-finder/sets/byte.go        | 203 ++++++++++++++++++++++++++++++
 peer-finder/sets/doc.go         |  20 +++
 peer-finder/sets/empty.go       |  23 ++++
 peer-finder/sets/int.go         | 203 ++++++++++++++++++++++++++++++
 peer-finder/sets/int64.go       | 203 ++++++++++++++++++++++++++++++
 peer-finder/sets/set_test.go    | 270 ++++++++++++++++++++++++++++++++++++++++
 peer-finder/sets/string.go      | 203 ++++++++++++++++++++++++++++++
 peer-finder/sets/types/BUILD    |  25 ++++
 peer-finder/sets/types/types.go |  32 +++++
 13 files changed, 1461 insertions(+)
 create mode 100644 peer-finder/Dockerfile
 create mode 100644 peer-finder/Makefile
 create mode 100644 peer-finder/peer-finder.go
 create mode 100644 peer-finder/sets/BUILD
 create mode 100644 peer-finder/sets/byte.go
 create mode 100644 peer-finder/sets/doc.go
 create mode 100644 peer-finder/sets/empty.go
 create mode 100644 peer-finder/sets/int.go
 create mode 100644 peer-finder/sets/int64.go
 create mode 100644 peer-finder/sets/set_test.go
 create mode 100644 peer-finder/sets/string.go
 create mode 100644 peer-finder/sets/types/BUILD
 create mode 100644 peer-finder/sets/types/types.go

(limited to 'peer-finder')

diff --git a/peer-finder/Dockerfile b/peer-finder/Dockerfile
new file mode 100644
index 0000000..137d2b4
--- /dev/null
+++ b/peer-finder/Dockerfile
@@ -0,0 +1,23 @@
+# Copyright 2016 The Kubernetes Authors 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.
+
+FROM gcr.io/google_containers/ubuntu-slim:0.2
+MAINTAINER Prashanth.B <beeps@google.com>
+
+RUN apt-get update && apt-get install -y wget bash dnsutils
+ADD peer-finder /peer-finder
+ADD peer-finder.go /peer-finder.go
+
+EXPOSE 9376
+ENTRYPOINT ["/peer-finder"]
diff --git a/peer-finder/Makefile b/peer-finder/Makefile
new file mode 100644
index 0000000..6e9a2cf
--- /dev/null
+++ b/peer-finder/Makefile
@@ -0,0 +1,33 @@
+# Copyright 2016 The Kubernetes Authors 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.
+
+all: server
+
+TAG = 0.1
+PREFIX = gcr.io/google_containers/peer-finder
+
+server: peer-finder.go
+	CGO_ENABLED=0 go build -a -installsuffix cgo --ldflags '-w' ./peer-finder.go
+
+release: server
+	gsutil cp peer-finder gs://kubernetes-release/pets/peer-finder
+
+container: server
+	docker build -t $(PREFIX):$(TAG) .
+
+push: container
+	gcloud docker push $(PREFIX):$(TAG)
+
+clean:
+	rm -f peer-finder
diff --git a/peer-finder/peer-finder.go b/peer-finder/peer-finder.go
new file mode 100644
index 0000000..5b48c1c
--- /dev/null
+++ b/peer-finder/peer-finder.go
@@ -0,0 +1,152 @@
+/*
+Copyright 2014 The Kubernetes Authors 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.
+*/
+
+// A small utility program to lookup hostnames of endpoints in a service.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"net"
+	"os"
+	"os/exec"
+	"sort"
+	"strings"
+	"time"
+
+	"./sets"
+//	"k8s.io/apimachinery/pkg/util/sets"
+)
+
+const (
+	svcLocalSuffix = "svc.cluster.local"
+	pollPeriod     = 1 * time.Second
+)
+
+var (
+	onChange  = flag.String("on-change", "", "Script to run on change, must accept a new line separated list of peers via stdin.")
+	onStart   = flag.String("on-start", "", "Script to run on start, must accept a new line separated list of peers via stdin.")
+	svc       = flag.String("service", "", "Governing service responsible for the DNS records of the domain this pod is in.")
+	namespace = flag.String("ns", "", "The namespace this pod is running in. If unspecified, the POD_NAMESPACE env var is used.")
+)
+
+func lookup(svcName string) (sets.String, error) {
+	endpoints := sets.NewString()
+	_, srvRecords, err := net.LookupSRV("", "", svcName)
+	if err != nil {
+		return endpoints, err
+	}
+	for _, srvRecord := range srvRecords {
+		// The SRV records ends in a "." for the root domain
+		ep := fmt.Sprintf("%v", srvRecord.Target[:len(srvRecord.Target)-1])
+		endpoints.Insert(ep)
+	}
+	return endpoints, nil
+}
+
+func resolve(s *sets.String, dnsName string) (error) {
+	ips, err := net.LookupIP(dnsName)
+	if (err == nil) {
+	    for _, ip := range ips {
+	        s.Insert(ip.String())
+	    }
+        }
+        return err
+}
+
+
+func shellOut(sendStdin, script string) {
+	log.Printf("execing: %v with stdin: %v", script, sendStdin)
+	// TODO: Switch to sending stdin from go
+	out, err := exec.Command("bash", "-c", fmt.Sprintf("echo -e '%v' | %v", sendStdin, script)).CombinedOutput()
+	if err != nil {
+		log.Fatalf("Failed to execute %v: %v, err: %v", script, string(out), err)
+	}
+	log.Print(string(out))
+}
+
+func main() {
+	flag.Parse()
+
+	ns := *namespace
+	if ns == "" {
+		ns = os.Getenv("POD_NAMESPACE")
+	}
+	if *svc == "" || ns == "" || (*onChange == "" && *onStart == "") {
+		log.Fatalf("Incomplete args, require -on-change and/or -on-start, -service and -ns or an env var for POD_NAMESPACE.")
+	}
+
+	hostname, err := os.Hostname()
+	if err != nil {
+		log.Fatalf("Failed to get hostname: %s", err)
+	}
+
+        matchIP := false
+	myName := strings.Join([]string{hostname, *svc, ns, svcLocalSuffix}, ".")
+	myIP := sets.NewString()
+	if (resolve(&myIP, myName) != nil) {
+	    if (resolve(&myIP, hostname) != nil) {
+	        log.Fatalf("Failed to resolve IP: %s", err)
+            } else {
+                myName = hostname
+                matchIP = true
+            }
+        }
+	log.Printf("MyName is: %v, MyIP is: %v, Match IP: %v.", myName, myIP.List(), matchIP)
+	
+	script := *onStart
+	if script == "" {
+		script = *onChange
+		log.Printf("No on-start supplied, on-change %v will be applied on start.", script)
+	}
+	for newPeers, peers := sets.NewString(), sets.NewString(); script != ""; time.Sleep(pollPeriod) {
+		newPeers, err = lookup(*svc)
+		if err != nil {
+			log.Printf("%v", err)
+			continue
+		}
+	        log.Printf("Peers is: %v.", newPeers.List())
+		if (newPeers.Equal(peers)) {
+		        continue
+                }
+                
+                if (!newPeers.Has(myName)) {
+		        if (matchIP) {
+                            peersIP := sets.NewString()
+		            for _, peer := range(newPeers.List()) {
+                                _ = resolve(&peersIP, peer)
+                            }
+                
+                            newIP := peersIP.Intersection(myIP)
+                            if (newIP.Len() == 0) {
+                                continue
+                            } 
+                        } else {
+			    continue
+                        }
+		}
+		peerList := newPeers.List()
+		sort.Strings(peerList)
+		log.Printf("Peer list updated\nwas %v\nnow %v", peers.List(), newPeers.List())
+		shellOut(strings.Join(peerList, "\n"), script)
+		peers = newPeers
+		script = *onChange
+	}
+	// TODO: Exit if there's no on-change?
+	log.Printf("Peer finder exiting")
+}
+
diff --git a/peer-finder/sets/BUILD b/peer-finder/sets/BUILD
new file mode 100644
index 0000000..ec2f234
--- /dev/null
+++ b/peer-finder/sets/BUILD
@@ -0,0 +1,71 @@
+package(default_visibility = ["//visibility:public"])
+
+load("@io_kubernetes_build//defs:go.bzl", "go_genrule")
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+    "go_test",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "byte.go",
+        "doc.go",
+        "empty.go",
+        "int.go",
+        "int64.go",
+        "string.go",
+    ],
+    importpath = "k8s.io/apimachinery/pkg/util/sets",
+)
+
+go_genrule(
+    name = "set-gen",
+    srcs = [
+        "//hack/boilerplate:boilerplate.go.txt",
+    ],
+    outs = [
+        "byte.go",
+        "doc.go",
+        "empty.go",
+        "int.go",
+        "int64.go",
+        "string.go",
+    ],
+    cmd = """
+$(location //vendor/k8s.io/code-generator/cmd/set-gen) \
+    --input-dirs ./vendor/k8s.io/apimachinery/pkg/util/sets/types \
+    --output-base $$(dirname $$(dirname $(location :byte.go))) \
+    --go-header-file $(location //hack/boilerplate:boilerplate.go.txt) \
+    --output-package sets
+    """,
+    go_deps = [
+        "//vendor/k8s.io/apimachinery/pkg/util/sets/types:go_default_library",
+    ],
+    tools = [
+        "//vendor/k8s.io/code-generator/cmd/set-gen",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["set_test.go"],
+    embed = [":go_default_library"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [
+        ":package-srcs",
+        "//staging/src/k8s.io/apimachinery/pkg/util/sets/types:all-srcs",
+    ],
+    tags = ["automanaged"],
+)
diff --git a/peer-finder/sets/byte.go b/peer-finder/sets/byte.go
new file mode 100644
index 0000000..a460e4b
--- /dev/null
+++ b/peer-finder/sets/byte.go
@@ -0,0 +1,203 @@
+/*
+Copyright 2017 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.
+*/
+
+// This file was autogenerated by set-gen. Do not edit it manually!
+
+package sets
+
+import (
+	"reflect"
+	"sort"
+)
+
+// sets.Byte is a set of bytes, implemented via map[byte]struct{} for minimal memory consumption.
+type Byte map[byte]Empty
+
+// New creates a Byte from a list of values.
+func NewByte(items ...byte) Byte {
+	ss := Byte{}
+	ss.Insert(items...)
+	return ss
+}
+
+// ByteKeySet creates a Byte from a keys of a map[byte](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func ByteKeySet(theMap interface{}) Byte {
+	v := reflect.ValueOf(theMap)
+	ret := Byte{}
+
+	for _, keyValue := range v.MapKeys() {
+		ret.Insert(keyValue.Interface().(byte))
+	}
+	return ret
+}
+
+// Insert adds items to the set.
+func (s Byte) Insert(items ...byte) {
+	for _, item := range items {
+		s[item] = Empty{}
+	}
+}
+
+// Delete removes all items from the set.
+func (s Byte) Delete(items ...byte) {
+	for _, item := range items {
+		delete(s, item)
+	}
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Byte) Has(item byte) bool {
+	_, contained := s[item]
+	return contained
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Byte) HasAll(items ...byte) bool {
+	for _, item := range items {
+		if !s.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Byte) HasAny(items ...byte) bool {
+	for _, item := range items {
+		if s.Has(item) {
+			return true
+		}
+	}
+	return false
+}
+
+// Difference returns a set of objects that are not in s2
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s Byte) Difference(s2 Byte) Byte {
+	result := NewByte()
+	for key := range s {
+		if !s2.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Byte) Union(s2 Byte) Byte {
+	result := NewByte()
+	for key := range s1 {
+		result.Insert(key)
+	}
+	for key := range s2 {
+		result.Insert(key)
+	}
+	return result
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Byte) Intersection(s2 Byte) Byte {
+	var walk, other Byte
+	result := NewByte()
+	if s1.Len() < s2.Len() {
+		walk = s1
+		other = s2
+	} else {
+		walk = s2
+		other = s1
+	}
+	for key := range walk {
+		if other.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Byte) IsSuperset(s2 Byte) bool {
+	for item := range s2 {
+		if !s1.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Byte) Equal(s2 Byte) bool {
+	return len(s1) == len(s2) && s1.IsSuperset(s2)
+}
+
+type sortableSliceOfByte []byte
+
+func (s sortableSliceOfByte) Len() int           { return len(s) }
+func (s sortableSliceOfByte) Less(i, j int) bool { return lessByte(s[i], s[j]) }
+func (s sortableSliceOfByte) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// List returns the contents as a sorted byte slice.
+func (s Byte) List() []byte {
+	res := make(sortableSliceOfByte, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	sort.Sort(res)
+	return []byte(res)
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Byte) UnsortedList() []byte {
+	res := make([]byte, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	return res
+}
+
+// Returns a single element from the set.
+func (s Byte) PopAny() (byte, bool) {
+	for key := range s {
+		s.Delete(key)
+		return key, true
+	}
+	var zeroValue byte
+	return zeroValue, false
+}
+
+// Len returns the size of the set.
+func (s Byte) Len() int {
+	return len(s)
+}
+
+func lessByte(lhs, rhs byte) bool {
+	return lhs < rhs
+}
diff --git a/peer-finder/sets/doc.go b/peer-finder/sets/doc.go
new file mode 100644
index 0000000..28a6a7d
--- /dev/null
+++ b/peer-finder/sets/doc.go
@@ -0,0 +1,20 @@
+/*
+Copyright 2017 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.
+*/
+
+// This file was autogenerated by set-gen. Do not edit it manually!
+
+// Package sets has auto-generated set types.
+package sets
diff --git a/peer-finder/sets/empty.go b/peer-finder/sets/empty.go
new file mode 100644
index 0000000..cd22b95
--- /dev/null
+++ b/peer-finder/sets/empty.go
@@ -0,0 +1,23 @@
+/*
+Copyright 2017 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.
+*/
+
+// This file was autogenerated by set-gen. Do not edit it manually!
+
+package sets
+
+// Empty is public since it is used by some internal API objects for conversions between external
+// string arrays and internal sets, and conversion logic requires public types today.
+type Empty struct{}
diff --git a/peer-finder/sets/int.go b/peer-finder/sets/int.go
new file mode 100644
index 0000000..0614e9f
--- /dev/null
+++ b/peer-finder/sets/int.go
@@ -0,0 +1,203 @@
+/*
+Copyright 2017 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.
+*/
+
+// This file was autogenerated by set-gen. Do not edit it manually!
+
+package sets
+
+import (
+	"reflect"
+	"sort"
+)
+
+// sets.Int is a set of ints, implemented via map[int]struct{} for minimal memory consumption.
+type Int map[int]Empty
+
+// New creates a Int from a list of values.
+func NewInt(items ...int) Int {
+	ss := Int{}
+	ss.Insert(items...)
+	return ss
+}
+
+// IntKeySet creates a Int from a keys of a map[int](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func IntKeySet(theMap interface{}) Int {
+	v := reflect.ValueOf(theMap)
+	ret := Int{}
+
+	for _, keyValue := range v.MapKeys() {
+		ret.Insert(keyValue.Interface().(int))
+	}
+	return ret
+}
+
+// Insert adds items to the set.
+func (s Int) Insert(items ...int) {
+	for _, item := range items {
+		s[item] = Empty{}
+	}
+}
+
+// Delete removes all items from the set.
+func (s Int) Delete(items ...int) {
+	for _, item := range items {
+		delete(s, item)
+	}
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Int) Has(item int) bool {
+	_, contained := s[item]
+	return contained
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Int) HasAll(items ...int) bool {
+	for _, item := range items {
+		if !s.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Int) HasAny(items ...int) bool {
+	for _, item := range items {
+		if s.Has(item) {
+			return true
+		}
+	}
+	return false
+}
+
+// Difference returns a set of objects that are not in s2
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s Int) Difference(s2 Int) Int {
+	result := NewInt()
+	for key := range s {
+		if !s2.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Int) Union(s2 Int) Int {
+	result := NewInt()
+	for key := range s1 {
+		result.Insert(key)
+	}
+	for key := range s2 {
+		result.Insert(key)
+	}
+	return result
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Int) Intersection(s2 Int) Int {
+	var walk, other Int
+	result := NewInt()
+	if s1.Len() < s2.Len() {
+		walk = s1
+		other = s2
+	} else {
+		walk = s2
+		other = s1
+	}
+	for key := range walk {
+		if other.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Int) IsSuperset(s2 Int) bool {
+	for item := range s2 {
+		if !s1.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Int) Equal(s2 Int) bool {
+	return len(s1) == len(s2) && s1.IsSuperset(s2)
+}
+
+type sortableSliceOfInt []int
+
+func (s sortableSliceOfInt) Len() int           { return len(s) }
+func (s sortableSliceOfInt) Less(i, j int) bool { return lessInt(s[i], s[j]) }
+func (s sortableSliceOfInt) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// List returns the contents as a sorted int slice.
+func (s Int) List() []int {
+	res := make(sortableSliceOfInt, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	sort.Sort(res)
+	return []int(res)
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Int) UnsortedList() []int {
+	res := make([]int, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	return res
+}
+
+// Returns a single element from the set.
+func (s Int) PopAny() (int, bool) {
+	for key := range s {
+		s.Delete(key)
+		return key, true
+	}
+	var zeroValue int
+	return zeroValue, false
+}
+
+// Len returns the size of the set.
+func (s Int) Len() int {
+	return len(s)
+}
+
+func lessInt(lhs, rhs int) bool {
+	return lhs < rhs
+}
diff --git a/peer-finder/sets/int64.go b/peer-finder/sets/int64.go
new file mode 100644
index 0000000..82e1ba7
--- /dev/null
+++ b/peer-finder/sets/int64.go
@@ -0,0 +1,203 @@
+/*
+Copyright 2017 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.
+*/
+
+// This file was autogenerated by set-gen. Do not edit it manually!
+
+package sets
+
+import (
+	"reflect"
+	"sort"
+)
+
+// sets.Int64 is a set of int64s, implemented via map[int64]struct{} for minimal memory consumption.
+type Int64 map[int64]Empty
+
+// New creates a Int64 from a list of values.
+func NewInt64(items ...int64) Int64 {
+	ss := Int64{}
+	ss.Insert(items...)
+	return ss
+}
+
+// Int64KeySet creates a Int64 from a keys of a map[int64](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func Int64KeySet(theMap interface{}) Int64 {
+	v := reflect.ValueOf(theMap)
+	ret := Int64{}
+
+	for _, keyValue := range v.MapKeys() {
+		ret.Insert(keyValue.Interface().(int64))
+	}
+	return ret
+}
+
+// Insert adds items to the set.
+func (s Int64) Insert(items ...int64) {
+	for _, item := range items {
+		s[item] = Empty{}
+	}
+}
+
+// Delete removes all items from the set.
+func (s Int64) Delete(items ...int64) {
+	for _, item := range items {
+		delete(s, item)
+	}
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Int64) Has(item int64) bool {
+	_, contained := s[item]
+	return contained
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Int64) HasAll(items ...int64) bool {
+	for _, item := range items {
+		if !s.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Int64) HasAny(items ...int64) bool {
+	for _, item := range items {
+		if s.Has(item) {
+			return true
+		}
+	}
+	return false
+}
+
+// Difference returns a set of objects that are not in s2
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s Int64) Difference(s2 Int64) Int64 {
+	result := NewInt64()
+	for key := range s {
+		if !s2.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Int64) Union(s2 Int64) Int64 {
+	result := NewInt64()
+	for key := range s1 {
+		result.Insert(key)
+	}
+	for key := range s2 {
+		result.Insert(key)
+	}
+	return result
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Int64) Intersection(s2 Int64) Int64 {
+	var walk, other Int64
+	result := NewInt64()
+	if s1.Len() < s2.Len() {
+		walk = s1
+		other = s2
+	} else {
+		walk = s2
+		other = s1
+	}
+	for key := range walk {
+		if other.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Int64) IsSuperset(s2 Int64) bool {
+	for item := range s2 {
+		if !s1.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Int64) Equal(s2 Int64) bool {
+	return len(s1) == len(s2) && s1.IsSuperset(s2)
+}
+
+type sortableSliceOfInt64 []int64
+
+func (s sortableSliceOfInt64) Len() int           { return len(s) }
+func (s sortableSliceOfInt64) Less(i, j int) bool { return lessInt64(s[i], s[j]) }
+func (s sortableSliceOfInt64) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// List returns the contents as a sorted int64 slice.
+func (s Int64) List() []int64 {
+	res := make(sortableSliceOfInt64, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	sort.Sort(res)
+	return []int64(res)
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Int64) UnsortedList() []int64 {
+	res := make([]int64, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	return res
+}
+
+// Returns a single element from the set.
+func (s Int64) PopAny() (int64, bool) {
+	for key := range s {
+		s.Delete(key)
+		return key, true
+	}
+	var zeroValue int64
+	return zeroValue, false
+}
+
+// Len returns the size of the set.
+func (s Int64) Len() int {
+	return len(s)
+}
+
+func lessInt64(lhs, rhs int64) bool {
+	return lhs < rhs
+}
diff --git a/peer-finder/sets/set_test.go b/peer-finder/sets/set_test.go
new file mode 100644
index 0000000..df722ec
--- /dev/null
+++ b/peer-finder/sets/set_test.go
@@ -0,0 +1,270 @@
+/*
+Copyright 2014 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 sets
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestStringSet(t *testing.T) {
+	s := String{}
+	s2 := String{}
+	if len(s) != 0 {
+		t.Errorf("Expected len=0: %d", len(s))
+	}
+	s.Insert("a", "b")
+	if len(s) != 2 {
+		t.Errorf("Expected len=2: %d", len(s))
+	}
+	s.Insert("c")
+	if s.Has("d") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+	if !s.Has("a") {
+		t.Errorf("Missing contents: %#v", s)
+	}
+	s.Delete("a")
+	if s.Has("a") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+	s.Insert("a")
+	if s.HasAll("a", "b", "d") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+	if !s.HasAll("a", "b") {
+		t.Errorf("Missing contents: %#v", s)
+	}
+	s2.Insert("a", "b", "d")
+	if s.IsSuperset(s2) {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+	s2.Delete("d")
+	if !s.IsSuperset(s2) {
+		t.Errorf("Missing contents: %#v", s)
+	}
+}
+
+func TestStringSetDeleteMultiples(t *testing.T) {
+	s := String{}
+	s.Insert("a", "b", "c")
+	if len(s) != 3 {
+		t.Errorf("Expected len=3: %d", len(s))
+	}
+
+	s.Delete("a", "c")
+	if len(s) != 1 {
+		t.Errorf("Expected len=1: %d", len(s))
+	}
+	if s.Has("a") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+	if s.Has("c") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+	if !s.Has("b") {
+		t.Errorf("Missing contents: %#v", s)
+	}
+
+}
+
+func TestNewStringSet(t *testing.T) {
+	s := NewString("a", "b", "c")
+	if len(s) != 3 {
+		t.Errorf("Expected len=3: %d", len(s))
+	}
+	if !s.Has("a") || !s.Has("b") || !s.Has("c") {
+		t.Errorf("Unexpected contents: %#v", s)
+	}
+}
+
+func TestStringSetList(t *testing.T) {
+	s := NewString("z", "y", "x", "a")
+	if !reflect.DeepEqual(s.List(), []string{"a", "x", "y", "z"}) {
+		t.Errorf("List gave unexpected result: %#v", s.List())
+	}
+}
+
+func TestStringSetDifference(t *testing.T) {
+	a := NewString("1", "2", "3")
+	b := NewString("1", "2", "4", "5")
+	c := a.Difference(b)
+	d := b.Difference(a)
+	if len(c) != 1 {
+		t.Errorf("Expected len=1: %d", len(c))
+	}
+	if !c.Has("3") {
+		t.Errorf("Unexpected contents: %#v", c.List())
+	}
+	if len(d) != 2 {
+		t.Errorf("Expected len=2: %d", len(d))
+	}
+	if !d.Has("4") || !d.Has("5") {
+		t.Errorf("Unexpected contents: %#v", d.List())
+	}
+}
+
+func TestStringSetHasAny(t *testing.T) {
+	a := NewString("1", "2", "3")
+
+	if !a.HasAny("1", "4") {
+		t.Errorf("expected true, got false")
+	}
+
+	if a.HasAny("0", "4") {
+		t.Errorf("expected false, got true")
+	}
+}
+
+func TestStringSetEquals(t *testing.T) {
+	// Simple case (order doesn't matter)
+	a := NewString("1", "2")
+	b := NewString("2", "1")
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	// It is a set; duplicates are ignored
+	b = NewString("2", "2", "1")
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	// Edge cases around empty sets / empty strings
+	a = NewString()
+	b = NewString()
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	b = NewString("1", "2", "3")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	b = NewString("1", "2", "")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	// Check for equality after mutation
+	a = NewString()
+	a.Insert("1")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	a.Insert("2")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	a.Insert("")
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	a.Delete("")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+}
+
+func TestStringUnion(t *testing.T) {
+	tests := []struct {
+		s1       String
+		s2       String
+		expected String
+	}{
+		{
+			NewString("1", "2", "3", "4"),
+			NewString("3", "4", "5", "6"),
+			NewString("1", "2", "3", "4", "5", "6"),
+		},
+		{
+			NewString("1", "2", "3", "4"),
+			NewString(),
+			NewString("1", "2", "3", "4"),
+		},
+		{
+			NewString(),
+			NewString("1", "2", "3", "4"),
+			NewString("1", "2", "3", "4"),
+		},
+		{
+			NewString(),
+			NewString(),
+			NewString(),
+		},
+	}
+
+	for _, test := range tests {
+		union := test.s1.Union(test.s2)
+		if union.Len() != test.expected.Len() {
+			t.Errorf("Expected union.Len()=%d but got %d", test.expected.Len(), union.Len())
+		}
+
+		if !union.Equal(test.expected) {
+			t.Errorf("Expected union.Equal(expected) but not true.  union:%v expected:%v", union.List(), test.expected.List())
+		}
+	}
+}
+
+func TestStringIntersection(t *testing.T) {
+	tests := []struct {
+		s1       String
+		s2       String
+		expected String
+	}{
+		{
+			NewString("1", "2", "3", "4"),
+			NewString("3", "4", "5", "6"),
+			NewString("3", "4"),
+		},
+		{
+			NewString("1", "2", "3", "4"),
+			NewString("1", "2", "3", "4"),
+			NewString("1", "2", "3", "4"),
+		},
+		{
+			NewString("1", "2", "3", "4"),
+			NewString(),
+			NewString(),
+		},
+		{
+			NewString(),
+			NewString("1", "2", "3", "4"),
+			NewString(),
+		},
+		{
+			NewString(),
+			NewString(),
+			NewString(),
+		},
+	}
+
+	for _, test := range tests {
+		intersection := test.s1.Intersection(test.s2)
+		if intersection.Len() != test.expected.Len() {
+			t.Errorf("Expected intersection.Len()=%d but got %d", test.expected.Len(), intersection.Len())
+		}
+
+		if !intersection.Equal(test.expected) {
+			t.Errorf("Expected intersection.Equal(expected) but not true.  intersection:%v expected:%v", intersection.List(), test.expected.List())
+		}
+	}
+}
diff --git a/peer-finder/sets/string.go b/peer-finder/sets/string.go
new file mode 100644
index 0000000..baef7a6
--- /dev/null
+++ b/peer-finder/sets/string.go
@@ -0,0 +1,203 @@
+/*
+Copyright 2017 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.
+*/
+
+// This file was autogenerated by set-gen. Do not edit it manually!
+
+package sets
+
+import (
+	"reflect"
+	"sort"
+)
+
+// sets.String is a set of strings, implemented via map[string]struct{} for minimal memory consumption.
+type String map[string]Empty
+
+// New creates a String from a list of values.
+func NewString(items ...string) String {
+	ss := String{}
+	ss.Insert(items...)
+	return ss
+}
+
+// StringKeySet creates a String from a keys of a map[string](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func StringKeySet(theMap interface{}) String {
+	v := reflect.ValueOf(theMap)
+	ret := String{}
+
+	for _, keyValue := range v.MapKeys() {
+		ret.Insert(keyValue.Interface().(string))
+	}
+	return ret
+}
+
+// Insert adds items to the set.
+func (s String) Insert(items ...string) {
+	for _, item := range items {
+		s[item] = Empty{}
+	}
+}
+
+// Delete removes all items from the set.
+func (s String) Delete(items ...string) {
+	for _, item := range items {
+		delete(s, item)
+	}
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s String) Has(item string) bool {
+	_, contained := s[item]
+	return contained
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s String) HasAll(items ...string) bool {
+	for _, item := range items {
+		if !s.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s String) HasAny(items ...string) bool {
+	for _, item := range items {
+		if s.Has(item) {
+			return true
+		}
+	}
+	return false
+}
+
+// Difference returns a set of objects that are not in s2
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s String) Difference(s2 String) String {
+	result := NewString()
+	for key := range s {
+		if !s2.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 String) Union(s2 String) String {
+	result := NewString()
+	for key := range s1 {
+		result.Insert(key)
+	}
+	for key := range s2 {
+		result.Insert(key)
+	}
+	return result
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 String) Intersection(s2 String) String {
+	var walk, other String
+	result := NewString()
+	if s1.Len() < s2.Len() {
+		walk = s1
+		other = s2
+	} else {
+		walk = s2
+		other = s1
+	}
+	for key := range walk {
+		if other.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 String) IsSuperset(s2 String) bool {
+	for item := range s2 {
+		if !s1.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 String) Equal(s2 String) bool {
+	return len(s1) == len(s2) && s1.IsSuperset(s2)
+}
+
+type sortableSliceOfString []string
+
+func (s sortableSliceOfString) Len() int           { return len(s) }
+func (s sortableSliceOfString) Less(i, j int) bool { return lessString(s[i], s[j]) }
+func (s sortableSliceOfString) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// List returns the contents as a sorted string slice.
+func (s String) List() []string {
+	res := make(sortableSliceOfString, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	sort.Sort(res)
+	return []string(res)
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s String) UnsortedList() []string {
+	res := make([]string, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	return res
+}
+
+// Returns a single element from the set.
+func (s String) PopAny() (string, bool) {
+	for key := range s {
+		s.Delete(key)
+		return key, true
+	}
+	var zeroValue string
+	return zeroValue, false
+}
+
+// Len returns the size of the set.
+func (s String) Len() int {
+	return len(s)
+}
+
+func lessString(lhs, rhs string) bool {
+	return lhs < rhs
+}
diff --git a/peer-finder/sets/types/BUILD b/peer-finder/sets/types/BUILD
new file mode 100644
index 0000000..50f7528
--- /dev/null
+++ b/peer-finder/sets/types/BUILD
@@ -0,0 +1,25 @@
+package(default_visibility = ["//visibility:public"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["types.go"],
+    importpath = "k8s.io/apimachinery/pkg/util/sets/types",
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+)
diff --git a/peer-finder/sets/types/types.go b/peer-finder/sets/types/types.go
new file mode 100644
index 0000000..4197356
--- /dev/null
+++ b/peer-finder/sets/types/types.go
@@ -0,0 +1,32 @@
+/*
+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 types just provides input types to the set generator. It also
+// contains a "go generate" block.
+// (You must first `go install k8s.io/code-generator/cmd/set-gen`)
+package types
+
+//go:generate set-gen -i k8s.io/kubernetes/pkg/util/sets/types
+
+type ReferenceSetTypes struct {
+	// These types all cause files to be generated.
+	// These types should be reflected in the output of
+	// the "//pkg/util/sets:set-gen" genrule.
+	a int64
+	b int
+	c byte
+	d string
+}
-- 
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