sip/pkg/services/loadbalancer.go

308 lines
8.7 KiB
Go

/*
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
https://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 services
import (
"bytes"
"html/template"
airshipv1 "sipcluster/pkg/api/v1"
airshipvms "sipcluster/pkg/vbmh"
"github.com/go-logr/logr"
"k8s.io/apimachinery/pkg/types"
appsv1 "k8s.io/api/apps/v1"
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"sigs.k8s.io/controller-runtime/pkg/client"
)
const (
// ConfigSecretName name of the haproxy config secret name/volume/mount
/* #nosec */
ConfigSecretName = "haproxy-config"
// DefaultBalancerImage is the image that will be used as load balancer
DefaultBalancerImage = "haproxy:2.3.2"
LoadBalancerServiceName = "loadbalancer"
)
func (lb loadBalancer) Deploy() error {
if lb.config.Image == "" {
lb.config.Image = DefaultBalancerImage
}
instance := LoadBalancerServiceName + "-" + lb.sipName.Name
labels := map[string]string{
// See https://kubernetes.io/docs/concepts/overview/working-with-objects/common-labels/#labels
"app.kubernetes.io/part-of": "sip",
"app.kubernetes.io/component": LoadBalancerServiceName,
"app.kubernetes.io/name": "haproxy",
"app.kubernetes.io/instance": instance,
}
deployment, secret, err := lb.generateDeploymentAndSecret(instance, labels)
if err != nil {
return err
}
lb.logger.Info("Applying loadbalancer secret", "secret", secret.GetNamespace()+"/"+secret.GetName())
err = applyRuntimeObject(client.ObjectKey{Name: secret.GetName(), Namespace: secret.GetNamespace()}, secret, lb.client)
if err != nil {
return err
}
// TODO: Validate Deployment becomes ready.
lb.logger.Info("Applying loadbalancer deployment", "deployment", deployment.GetNamespace()+"/"+deployment.GetName())
err = applyRuntimeObject(client.ObjectKey{Name: deployment.GetName(), Namespace: deployment.GetNamespace()},
deployment, lb.client)
if err != nil {
return err
}
// TODO: Validate Service becomes ready.
lbService := lb.generateService(instance, labels)
lb.logger.Info("Applying loadbalancer service", "service", lbService.GetNamespace()+"/"+lbService.GetName())
err = applyRuntimeObject(client.ObjectKey{Name: lbService.GetName(), Namespace: lbService.GetNamespace()},
lbService, lb.client)
if err != nil {
return err
}
return nil
}
func (lb loadBalancer) generateDeploymentAndSecret(instance string, labels map[string]string) (*appsv1.Deployment,
*corev1.Secret, error) {
secret, err := lb.generateSecret(instance)
if err != nil {
return nil, nil, err
}
deployment := &appsv1.Deployment{
ObjectMeta: metav1.ObjectMeta{
Name: instance,
Namespace: lb.sipName.Namespace,
Labels: labels,
},
Spec: appsv1.DeploymentSpec{
Replicas: int32Ptr(1),
Selector: &metav1.LabelSelector{
MatchLabels: labels,
},
Template: corev1.PodTemplateSpec{
ObjectMeta: metav1.ObjectMeta{
Labels: labels,
},
Spec: corev1.PodSpec{
Containers: []corev1.Container{
{
Name: LoadBalancerServiceName,
Image: lb.config.Image,
ImagePullPolicy: corev1.PullIfNotPresent,
Ports: []corev1.ContainerPort{
{
Name: "http",
ContainerPort: 6443,
},
},
VolumeMounts: []corev1.VolumeMount{
{
Name: ConfigSecretName,
MountPath: "/usr/local/etc/haproxy",
},
},
},
},
Volumes: []corev1.Volume{
{
Name: ConfigSecretName,
VolumeSource: corev1.VolumeSource{
Secret: &corev1.SecretVolumeSource{
SecretName: secret.GetName(),
},
},
},
},
},
},
},
}
return deployment, secret, nil
}
func (lb loadBalancer) generateSecret(instance string) (*corev1.Secret, error) {
p := proxy{
FrontPort: 6443,
Backends: make([]backend, 0),
}
for _, machine := range lb.machines.Machines {
if machine.VMRole == airshipv1.VMControlPlane {
name := machine.BMH.Name
namespace := machine.BMH.Namespace
ip, exists := machine.Data.IPOnInterface[lb.config.NodeInterface]
if !exists {
lb.logger.Info("Machine does not have backend interface to be forwarded to",
"interface", lb.config.NodeInterface,
"machine", namespace+"/"+name,
)
continue
}
p.Backends = append(p.Backends, backend{IP: ip, Name: machine.BMH.Name, Port: 6443})
}
}
secretData, err := generateTemplate(p)
if err != nil {
return nil, err
}
return &corev1.Secret{
ObjectMeta: metav1.ObjectMeta{
Name: instance,
Namespace: lb.sipName.Namespace,
},
Type: corev1.SecretTypeOpaque,
Data: map[string][]byte{
"haproxy.cfg": secretData,
},
}, nil
}
func (lb loadBalancer) generateService(instance string, labels map[string]string) *corev1.Service {
return &corev1.Service{
ObjectMeta: metav1.ObjectMeta{
Name: instance,
Namespace: lb.sipName.Namespace,
},
Spec: corev1.ServiceSpec{
Ports: []corev1.ServicePort{
{
Name: "http",
Port: 6443,
NodePort: int32(lb.config.NodePort),
},
},
Selector: labels,
Type: corev1.ServiceTypeNodePort,
},
}
}
type proxy struct {
FrontPort int
Backends []backend
}
type backend struct {
IP string
Name string
Port int
}
type loadBalancer struct {
client client.Client
sipName types.NamespacedName
logger logr.Logger
config airshipv1.SIPClusterService
machines *airshipvms.MachineList
}
func newLB(name, namespace string,
logger logr.Logger,
config airshipv1.SIPClusterService,
machines *airshipvms.MachineList,
client client.Client) loadBalancer {
return loadBalancer{
sipName: types.NamespacedName{
Name: name,
Namespace: namespace,
},
logger: logger,
config: config,
machines: machines,
client: client,
}
}
func (lb loadBalancer) Finalize() error {
// implete to delete loadbalancer
return nil
}
func generateTemplate(p proxy) ([]byte, error) {
tmpl, err := template.New("haproxy-config").Parse(defaultTemplate)
if err != nil {
return nil, err
}
w := bytes.NewBuffer([]byte{})
if err := tmpl.Execute(w, p); err != nil {
return nil, err
}
rendered := w.Bytes()
return rendered, nil
}
var defaultTemplate = `global
log stdout format raw local0 notice
daemon
defaults
mode http
log global
option httplog
option dontlognull
retries 1
# Configures the timeout for a connection request to be left pending in a queue
# (connection requests are queued once the maximum number of connections is reached).
timeout queue 30s
# Configures the timeout for a connection to a backend server to be established.
timeout connect 30s
# Configures the timeout for inactivity during periods when we would expect
# the client to be speaking. For usability of 'kubectl exec', the timeout should
# be long enough to cover inactivity due to idleness of interactive sessions.
timeout client 600s
# Configures the timeout for inactivity during periods when we would expect
# the server to be speaking. For usability of 'kubectl log -f', the timeout should
# be long enough to cover inactivity due to the lack of new logs.
timeout server 600s
#---------------------------------------------------------------------
# apiserver frontend which proxys to the masters
#---------------------------------------------------------------------
frontend apiserver
bind *:{{ .FrontPort }}
mode tcp
option tcplog
default_backend kube-apiservers
#---------------------------------------------------------------------
# round robin balancing for apiserver
#---------------------------------------------------------------------
backend kube-apiservers
mode tcp
balance roundrobin
option httpchk GET /readyz
http-check expect status 200
option log-health-checks
# Observed apiserver returns 500 for around 10s when 2nd cp node joins.
# downinter 2s makes it check more frequently to recover from that state sooner.
# Also changing fall to 4 so that it takes longer (4 failures) for it to take down a backend.
default-server check check-ssl verify none inter 5s downinter 2s fall 4 on-marked-down shutdown-sessions
{{- range .Backends }}
{{- $backEnd := . }}
server {{ $backEnd.Name }} {{ $backEnd.IP }}:{{ $backEnd.Port }}
{{ end -}}`