Add support for rate limiting in ingress rule locations

ingress/controllers/nginx/nginx.tmpl

@@ -156,6 +156,12 @@ http {
  }
  {{ end }}
 
+ {{/* build all the required rate limit zones. Each annotation requires a dedicated zone */}}
+ {{/* 1MB -> 16 thousand 64-byte states or about 8 thousand 128-byte states */}}
+ {{ $zone := range (buildRateLimitZones .servers) }}
+ {{ $zone }}
+ {{ end }}
+
  {{ range $server := .servers }}
  server {
  server_name {{ $server.Name }};

ingress/controllers/nginx/nginx/ratelimit/main.go

@@ -0,0 +1,131 @@
+/*
+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.
+*/
+
+package ratelimit
+
+import (
+ "errors"
+ "fmt"
+ "strconv"
+
+ "k8s.io/kubernetes/pkg/apis/extensions"
+)
+
+const (
+ limitIp = "ingress-nginx.kubernetes.io/limit-connections"
+ limitRps = "ingress-nginx.kubernetes.io/limit-rps"
+
+ // allow 5 times the specified limit as burst
+ defBurst = 5
+
+ // 1MB -> 16 thousand 64-byte states or about 8 thousand 128-byte states
+ // default is 5MB
+ defSharedSize = 5
+)
+
+var (
+ // ErrInvalidRateLimit is returned when the annotation caontains invalid values
+ ErrInvalidRateLimit = errors.New("invalid rate limit value. Must be > 0")
+)
+
+// ErrMissingAnnotations is returned when the ingress rule
+// does not contains annotations related with rate limit
+type ErrMissingAnnotations struct {
+ msg string
+}
+
+func (e ErrMissingAnnotations) Error() string {
+ return e.msg
+}
+
+// RateLimit returns rate limit configuration for an Ingress rule
+// Is possible to limit the number of connections per IP address or
+// connections per second.
+// Note: Is possible to specify both limits
+type RateLimit struct {
+ // Connections indicates a limit with the number of connections per IP address
+ Connections Zone
+ // RPS indicates a limit with the number of connections per second
+ RPS Zone
+}
+
+// Zone returns information about the rate limit
+type Zone struct {
+ Name string
+ Limit int
+ Burst int
+ // SharedSize amount of shared memory for the zone
+ SharedSize int
+}
+
+type ingAnnotations map[string]string
+
+func (a ingAnnotations) limitIp() int {
+ val, ok := a[limitIp]
+ if ok {
+ if i, err := strconv.Atoi(val); err == nil {
+ return i
+ }
+ }
+
+ return -1
+}
+
+func (a ingAnnotations) limitRps() int {
+ val, ok := a[limitRps]
+ if ok {
+ if i, err := strconv.Atoi(val); err == nil {
+ return i
+ }
+ }
+
+ return -1
+}
+
+// ParseAnnotations parses the annotations contained in the ingress
+// rule used to rewrite the defined paths
+func ParseAnnotations(ing *extensions.Ingress) (*RateLimit, error) {
+ if ing.GetAnnotations() == nil {
+ return &RateLimit{}, ErrMissingAnnotations{"no annotations present"}
+ }
+
+ rps := ingAnnotations(ing.GetAnnotations()).limitRps()
+ conn := ingAnnotations(ing.GetAnnotations()).limitIp()
+
+ if rps == 0 && conn == 0 {
+ return &RateLimit{
+ Connections: Zone{"", -1, -1, 1},
+ RPS: Zone{"", -1, -1, 1},
+ }, ErrInvalidRateLimit
+ }
+
+ zoneName := fmt.Sprintf("%v_%v", ing.GetNamespace(), ing.GetName())
+
+ return &RateLimit{
+ Connections: Zone{
+ Name: fmt.Sprintf("%v_conn", zoneName),
+ Limit: conn,
+ Burst: conn * defBurst,
+ SharedSize: defSharedSize,
+ },
+ RPS: Zone{
+ Name: fmt.Sprintf("%v_rps", zoneName),
+ Limit: rps,
+ Burst: conn * defBurst,
+ SharedSize: defSharedSize,
+ },
+ }, nil
+}

ingress/controllers/nginx/nginx/ratelimit/main_test.go

@@ -0,0 +1,129 @@
+/*
+Copyright 2015 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.
+*/
+
+package ratelimit
+
+import (
+ "testing"
+
+ "k8s.io/kubernetes/pkg/api"
+ "k8s.io/kubernetes/pkg/apis/extensions"
+ "k8s.io/kubernetes/pkg/util/intstr"
+)
+
+func buildIngress() *extensions.Ingress {
+ defaultBackend := extensions.IngressBackend{
+ ServiceName: "default-backend",
+ ServicePort: intstr.FromInt(80),
+ }
+
+ return &extensions.Ingress{
+ ObjectMeta: api.ObjectMeta{
+ Name: "foo",
+ Namespace: api.NamespaceDefault,
+ },
+ Spec: extensions.IngressSpec{
+ Backend: &extensions.IngressBackend{
+ ServiceName: "default-backend",
+ ServicePort: intstr.FromInt(80),
+ },
+ Rules: []extensions.IngressRule{
+ {
+ Host: "foo.bar.com",
+ IngressRuleValue: extensions.IngressRuleValue{
+ HTTP: &extensions.HTTPIngressRuleValue{
+ Paths: []extensions.HTTPIngressPath{
+ {
+ Path: "/foo",
+ Backend: defaultBackend,
+ },
+ },
+ },
+ },
+ },
+ },
+ },
+ }
+}
+
+func TestAnnotations(t *testing.T) {
+ ing := buildIngress()
+
+ lip := ingAnnotations(ing.GetAnnotations()).limitIp()
+ if lip != -1 {
+ t.Error("Expected -1 in limit by ip but %v was returned", lip)
+ }
+
+ lrps := ingAnnotations(ing.GetAnnotations()).limitRps()
+ if lrps != -1 {
+ t.Error("Expected -1 in limit by rps but %v was returend", lrps)
+ }
+
+ data := map[string]string{}
+ data[limitIp] = "5"
+ data[limitRps] = "100"
+ ing.SetAnnotations(data)
+
+ lip = ingAnnotations(ing.GetAnnotations()).limitIp()
+ if lip != 5 {
+ t.Error("Expected %v in limit by ip but %v was returend", lip)
+ }
+
+ lrps = ingAnnotations(ing.GetAnnotations()).limitRps()
+ if lrps != 100 {
+ t.Error("Expected 100 in limit by rps but %v was returend", lrps)
+ }
+}
+
+func TestWithoutAnnotations(t *testing.T) {
+ ing := buildIngress()
+ _, err := ParseAnnotations(ing)
+ if err == nil {
+ t.Error("Expected error with ingress without annotations")
+ }
+}
+
+func TestBadRateLimiting(t *testing.T) {
+ ing := buildIngress()
+
+ data := map[string]string{}
+ data[limitIp] = "0"
+ data[limitRps] = "0"
+ ing.SetAnnotations(data)
+
+ _, err := ParseAnnotations(ing)
+ if err == nil {
+ t.Errorf("Expected error with invalid limits (0)")
+ }
+
+ data = map[string]string{}
+ data[limitIp] = "5"
+ data[limitRps] = "100"
+ ing.SetAnnotations(data)
+
+ rateLimit, err := ParseAnnotations(ing)
+ if err != nil {
+ t.Errorf("Uxpected error: %v", err)
+ }
+
+ if rateLimit.Connections.Limit != 5 {
+ t.Error("Expected 5 in limit by ip but %v was returend", rateLimit.Connections)
+ }
+
+ if rateLimit.RPS.Limit != 100 {
+ t.Error("Expected 100 in limit by rps but %v was returend", rateLimit.RPS)
+ }
+}