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reflect latest change in restart logic

This commit is contained in:
Felix Kunde 2021-10-26 17:06:06 +02:00
parent db76b8c642 1eafd688d0
commit a5acfd3b42
9 changed files with 303 additions and 69 deletions
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1
docker/logical-backup/Dockerfile
View File

@ -23,6 +23,7 @@ RUN apt-get update \
&& curl --silent https://www.postgresql.org/media/keys/ACCC4CF8.asc | apt-key add - \
&& apt-get update \
&& apt-get install --no-install-recommends -y \
postgresql-client-14 \
postgresql-client-13 \
postgresql-client-12 \
postgresql-client-11 \

4
docs/reference/cluster_manifest.md
View File

@ -110,7 +110,7 @@ These parameters are grouped directly under the `spec` key in the manifest.
`CREATEDB`, `BYPASSURL`. A login user is created by default unless NOLOGIN is
specified, in which case the operator creates a role. One can specify empty
flags by providing a JSON empty array '*[]*'. If the config option
`enable_cross_namespace_secrets` is enabled you can specify the namespace in
`enable_cross_namespace_secret` is enabled you can specify the namespace in
the user name in the form `{namespace}.{username}` and the operator will
create the K8s secret in that namespace. The part after the first `.` is
considered to be the user name. Optional.
@ -215,7 +215,7 @@ information, see [user docs](../user.md#prepared-databases-with-roles-and-defaul
* **secretNamespace**
for each default LOGIN role the operator will create a secret. You can
specify the namespace in which these secrets will get created, if
`enable_cross_namespace_secrets` is set to `true` in the config. Otherwise,
`enable_cross_namespace_secret` is set to `true` in the config. Otherwise,
the cluster namespace is used.
## Postgres parameters

2
docs/reference/operator_parameters.md
View File

@ -264,7 +264,7 @@ configuration they are grouped under the `kubernetes` key.
[admin docs](../administrator.md#pod-disruption-budget) for more information.
Default is true.
* **enable_cross_namespace_secrets**
* **enable_cross_namespace_secret**
To allow secrets in a different namespace other than the Postgres cluster
namespace. Once enabled, specify the namespace in the user name under the
`users` section in the form `{namespace}.{username}`. The default is `false`.

2
e2e/Dockerfile
View File

@ -16,7 +16,7 @@ RUN apt-get update \
curl \
vim \
&& pip3 install --no-cache-dir -r requirements.txt \
&& curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.18.0/bin/linux/amd64/kubectl \
&& curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.22.0/bin/linux/amd64/kubectl \
&& chmod +x ./kubectl \
&& mv ./kubectl /usr/local/bin/kubectl \
&& apt-get clean \

2
e2e/run.sh
View File

@ -8,7 +8,7 @@ IFS=$'\n\t'
readonly cluster_name="postgres-operator-e2e-tests"
readonly kubeconfig_path="/tmp/kind-config-${cluster_name}"
readonly spilo_image="registry.opensource.zalan.do/acid/spilo-13-e2e:0.3"
readonly spilo_image="registry.opensource.zalan.do/acid/spilo-14-e2e:0.1"
readonly e2e_test_runner_image="registry.opensource.zalan.do/acid/postgres-operator-e2e-tests-runner:0.3"
export GOPATH=${GOPATH-~/go}

79
e2e/tests/test_e2e.py
View File

@ -11,8 +11,8 @@ from kubernetes import client
from tests.k8s_api import K8s
from kubernetes.client.rest import ApiException
SPILO_CURRENT = "registry.opensource.zalan.do/acid/spilo-13-e2e:0.3"
SPILO_LAZY = "registry.opensource.zalan.do/acid/spilo-13-e2e:0.4"
SPILO_CURRENT = "registry.opensource.zalan.do/acid/spilo-14-e2e:0.1"
SPILO_LAZY = "registry.opensource.zalan.do/acid/spilo-14-e2e:0.2"
def to_selector(labels):
@ -85,6 +85,7 @@ class EndToEndTestCase(unittest.TestCase):
# set a single K8s wrapper for all tests
k8s = cls.k8s = K8s()
cluster_label = 'application=spilo,cluster-name=acid-minimal-cluster'
# remove existing local storage class and create hostpath class
try:
@ -150,8 +151,8 @@ class EndToEndTestCase(unittest.TestCase):
result = k8s.create_with_kubectl("manifests/minimal-postgres-manifest.yaml")
print('stdout: {}, stderr: {}'.format(result.stdout, result.stderr))
try:
k8s.wait_for_pod_start('spilo-role=master')
k8s.wait_for_pod_start('spilo-role=replica')
k8s.wait_for_pod_start('spilo-role=master,' + cluster_label)
k8s.wait_for_pod_start('spilo-role=replica,' + cluster_label)
except timeout_decorator.TimeoutError:
print('Operator log: {}'.format(k8s.get_operator_log()))
raise
@ -1064,12 +1065,13 @@ class EndToEndTestCase(unittest.TestCase):
via restarting cluster through Patroni's rest api
'''
k8s = self.k8s
masterPod = k8s.get_cluster_leader_pod()
labels = 'application=spilo,cluster-name=acid-minimal-cluster,spilo-role=master'
creationTimestamp = masterPod.metadata.creation_timestamp
leader = k8s.get_cluster_leader_pod()
replica = k8s.get_cluster_replica_pod()
masterCreationTimestamp = leader.metadata.creation_timestamp
replicaCreationTimestamp = replica.metadata.creation_timestamp
new_max_connections_value = "50"
# adjust max_connection
# adjust Postgres config
pg_patch_config = {
"spec": {
"postgresql": {
@ -1098,7 +1100,7 @@ class EndToEndTestCase(unittest.TestCase):
self.eventuallyEqual(lambda: k8s.get_operator_state(), {"0": "idle"}, "Operator does not get in sync")
def compare_config():
effective_config = k8s.patroni_rest(masterPod.metadata.name, "config")
effective_config = k8s.patroni_rest(leader.metadata.name, "config")
desired_config = pg_patch_config["spec"]["patroni"]
desired_parameters = pg_patch_config["spec"]["postgresql"]["parameters"]
effective_parameters = effective_config["postgresql"]["parameters"]
@ -1115,19 +1117,63 @@ class EndToEndTestCase(unittest.TestCase):
"synchronous_mode not updated")
return True
# check if Patroni config has been updated
self.eventuallyTrue(compare_config, "Postgres config not applied")
# make sure that pods were not recreated
leader = k8s.get_cluster_leader_pod()
replica = k8s.get_cluster_replica_pod()
self.assertEqual(masterCreationTimestamp, leader.metadata.creation_timestamp,
"Master pod creation timestamp is updated")
self.assertEqual(replicaCreationTimestamp, replica.metadata.creation_timestamp,
"Master pod creation timestamp is updated")
# query max_connections setting
setting_query = """
SELECT setting
FROM pg_settings
WHERE name = 'max_connections';
"""
self.eventuallyEqual(lambda: self.query_database(masterPod.metadata.name, "postgres", setting_query)[0], new_max_connections_value,
"New max_connections setting not applied", 10, 5)
self.eventuallyEqual(lambda: self.query_database(leader.metadata.name, "postgres", setting_query)[0], new_max_connections_value,
"New max_connections setting not applied on master", 10, 5)
self.eventuallyNotEqual(lambda: self.query_database(replica.metadata.name, "postgres", setting_query)[0], new_max_connections_value,
"Expected max_connections not to be updated on replica since Postgres was restarted there first", 10, 5)
# make sure that pod wasn't recreated
self.assertEqual(creationTimestamp, masterPod.metadata.creation_timestamp,
"Master pod creation timestamp is updated")
# the next sync should restart the replica because it has pending_restart flag set
# force next sync by deleting the operator pod
k8s.delete_operator_pod()
self.eventuallyEqual(lambda: k8s.get_operator_state(), {"0": "idle"}, "Operator does not get in sync")
self.eventuallyEqual(lambda: self.query_database(replica.metadata.name, "postgres", setting_query)[0], new_max_connections_value,
"New max_connections setting not applied on replica", 10, 5)
# decrease max_connections again
# this time restart will be correct and new value should appear on both instances
lower_max_connections_value = "30"
pg_patch_max_connections = {
"spec": {
"postgresql": {
"parameters": {
"max_connections": lower_max_connections_value
}
}
}
}
k8s.api.custom_objects_api.patch_namespaced_custom_object(
"acid.zalan.do", "v1", "default", "postgresqls", "acid-minimal-cluster", pg_patch_max_connections)
self.eventuallyEqual(lambda: k8s.get_operator_state(), {"0": "idle"}, "Operator does not get in sync")
# check Patroni config again
pg_patch_config["spec"]["postgresql"]["parameters"]["max_connections"] = lower_max_connections_value
self.eventuallyTrue(compare_config, "Postgres config not applied")
# and query max_connections setting again
self.eventuallyEqual(lambda: self.query_database(leader.metadata.name, "postgres", setting_query)[0], lower_max_connections_value,
"Previous max_connections setting not applied on master", 10, 5)
self.eventuallyEqual(lambda: self.query_database(replica.metadata.name, "postgres", setting_query)[0], lower_max_connections_value,
"Previous max_connections setting not applied on replica", 10, 5)
except timeout_decorator.TimeoutError:
print('Operator log: {}'.format(k8s.get_operator_log()))
@ -1554,6 +1600,7 @@ class EndToEndTestCase(unittest.TestCase):
Toggle pod anti affinty to distribute pods accross nodes (replica in particular).
'''
k8s = self.k8s
cluster_label = 'application=spilo,cluster-name=acid-minimal-cluster'
failover_targets = self.get_failover_targets(master_node, replica_nodes)
# enable pod anti affintiy in config map which should trigger movement of replica
@ -1572,8 +1619,8 @@ class EndToEndTestCase(unittest.TestCase):
}
}
k8s.update_config(patch_disable_antiaffinity, "disable antiaffinity")
k8s.wait_for_pod_start('spilo-role=master')
k8s.wait_for_pod_start('spilo-role=replica')
k8s.wait_for_pod_start('spilo-role=master,' + cluster_label)
k8s.wait_for_pod_start('spilo-role=replica,' + cluster_label)
return True
def list_databases(self, pod_name):

123
pkg/cluster/sync.go
View File

@ -6,6 +6,7 @@ import (
"fmt"
"reflect"
"regexp"
"strconv"
"strings"
"time"
@ -20,6 +21,14 @@ import (
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)
var requireMasterRestartWhenDecreased = []string{
"max_connections",
"max_prepared_transactions",
"max_locks_per_transaction",
"max_worker_processes",
"max_wal_senders",
}
// Sync syncs the cluster, making sure the actual Kubernetes objects correspond to what is defined in the manifest.
// Unlike the update, sync does not error out if some objects do not exist and takes care of creating them.
func (c *Cluster) Sync(newSpec *acidv1.Postgresql) error {
@ -270,11 +279,9 @@ func (c *Cluster) syncPodDisruptionBudget(isUpdate bool) error {
func (c *Cluster) syncStatefulSet() error {
var (
masterPod *v1.Pod
restartTTL uint32
instanceRestartRequired bool
restartWait uint32
restartMasterFirst bool
)
podsToRecreate := make([]v1.Pod, 0)
switchoverCandidates := make([]spec.NamespacedName, 0)
@ -408,35 +415,43 @@ func (c *Cluster) syncStatefulSet() error {
c.logger.Warningf("could not get Postgres config from pod %s: %v", podName, err)
continue
}
restartWait = patroniConfig.LoopWait
// empty config probably means cluster is not fully initialized yet, e.g. restoring from backup
// do not attempt a restart
if !reflect.DeepEqual(patroniConfig, emptyPatroniConfig) || len(pgParameters) > 0 {
instanceRestartRequired, err = c.checkAndSetGlobalPostgreSQLConfiguration(&pod, patroniConfig, c.Spec.Patroni, pgParameters, c.Spec.Parameters)
restartMasterFirst, err = c.checkAndSetGlobalPostgreSQLConfiguration(&pod, patroniConfig, c.Spec.Patroni, pgParameters, c.Spec.Parameters)
if err != nil {
c.logger.Warningf("could not set PostgreSQL configuration options for pod %s: %v", podName, err)
continue
}
restartTTL = patroniConfig.TTL
// it could take up to LoopWait to apply the config
time.Sleep(time.Duration(restartWait)*time.Second + time.Second*2)
break
}
}
// if the config update requires a restart, call Patroni restart for replicas first, then master
if instanceRestartRequired {
c.logger.Debug("restarting Postgres server within pods")
for i, pod := range pods {
role := PostgresRole(pod.Labels[c.OpConfig.PodRoleLabel])
if role == Master {
masterPod = &pods[i]
continue
}
c.restartInstance(&pod)
time.Sleep(time.Duration(restartTTL) * time.Second)
// restart instances if required
remainingPods := make([]*v1.Pod, 0)
skipRole := Master
if restartMasterFirst {
skipRole = Replica
}
for i, pod := range pods {
role := PostgresRole(pod.Labels[c.OpConfig.PodRoleLabel])
if role == skipRole {
remainingPods = append(remainingPods, &pods[i])
continue
}
c.restartInstance(&pod, restartWait)
}
if masterPod != nil {
c.restartInstance(masterPod)
// in most cases only the master should be left to restart
if len(remainingPods) > 0 {
for _, remainingPod := range remainingPods {
c.restartInstance(remainingPod, restartWait)
}
}
@ -453,19 +468,27 @@ func (c *Cluster) syncStatefulSet() error {
return nil
}
func (c *Cluster) restartInstance(pod *v1.Pod) {
func (c *Cluster) restartInstance(pod *v1.Pod, restartWait uint32) {
podName := util.NameFromMeta(pod.ObjectMeta)
role := PostgresRole(pod.Labels[c.OpConfig.PodRoleLabel])
c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", fmt.Sprintf("restarting Postgres server within %s pod %s", role, pod.Name))
if err := c.patroni.Restart(pod); err != nil {
c.logger.Warningf("could not restart Postgres server within %s pod %s: %v", role, podName, err)
// if the config update requires a restart, call Patroni restart
memberData, err := c.patroni.GetMemberData(pod)
if err != nil {
c.logger.Debugf("could not get member data of %s pod %s - skipping possible restart attempt: %v", role, podName, err)
return
}
c.logger.Debugf("Postgres server successfuly restarted in %s pod %s", role, podName)
c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", fmt.Sprintf("Postgres server restart done for %s pod %s", role, pod.Name))
// do restart only when it is pending
if memberData.PendingRestart {
c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", fmt.Sprintf("restarting Postgres server within %s pod %s", role, pod.Name))
if err := c.patroni.Restart(pod); err != nil {
c.logger.Warningf("could not restart Postgres server within %s pod %s: %v", role, podName, err)
return
}
time.Sleep(time.Duration(restartWait) * time.Second)
c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", fmt.Sprintf("Postgres server restart done for %s pod %s", role, pod.Name))
}
}
// AnnotationsToPropagate get the annotations to update if required
@ -505,20 +528,10 @@ func (c *Cluster) AnnotationsToPropagate(annotations map[string]string) map[stri
func (c *Cluster) checkAndSetGlobalPostgreSQLConfiguration(pod *v1.Pod, effectivePatroniConfig, desiredPatroniConfig acidv1.Patroni, effectivePgParameters, desiredPgParameters map[string]string) (bool, error) {
configToSet := make(map[string]interface{})
parametersToSet := make(map[string]string)
restartMaster := make([]bool, 0)
requiresMasterRestart := false
// compare parameters under postgresql section with c.Spec.Postgresql.Parameters from manifest
for desiredOption, desiredValue := range desiredPgParameters {
effectiveValue := effectivePgParameters[desiredOption]
if isBootstrapOnlyParameter(desiredOption) && (effectiveValue != desiredValue) {
parametersToSet[desiredOption] = desiredValue
}
}
if len(parametersToSet) > 0 {
configToSet["postgresql"] = map[string]interface{}{constants.PatroniPGParametersParameterName: parametersToSet}
}
// compare other options from config with c.Spec.Patroni from manifest
// compare effective and desired Patroni config options
if desiredPatroniConfig.LoopWait > 0 && desiredPatroniConfig.LoopWait != effectivePatroniConfig.LoopWait {
configToSet["loop_wait"] = desiredPatroniConfig.LoopWait
}
@ -555,6 +568,34 @@ func (c *Cluster) checkAndSetGlobalPostgreSQLConfiguration(pod *v1.Pod, effectiv
configToSet["slots"] = slotsToSet
}
// compare parameters under postgresql section with c.Spec.Postgresql.Parameters from manifest
for desiredOption, desiredValue := range desiredPgParameters {
effectiveValue := effectivePgParameters[desiredOption]
if isBootstrapOnlyParameter(desiredOption) && (effectiveValue != desiredValue) {
parametersToSet[desiredOption] = desiredValue
if util.SliceContains(requireMasterRestartWhenDecreased, desiredOption) {
effectiveValueNum, errConv := strconv.Atoi(effectiveValue)
desiredValueNum, errConv2 := strconv.Atoi(desiredValue)
if errConv != nil || errConv2 != nil {
continue
}
if effectiveValueNum > desiredValueNum {
restartMaster = append(restartMaster, true)
continue
}
}
restartMaster = append(restartMaster, false)
}
}
if !util.SliceContains(restartMaster, false) && len(configToSet) == 0 {
requiresMasterRestart = true
}
if len(parametersToSet) > 0 {
configToSet["postgresql"] = map[string]interface{}{constants.PatroniPGParametersParameterName: parametersToSet}
}
if len(configToSet) == 0 {
return false, nil
}
@ -570,10 +611,10 @@ func (c *Cluster) checkAndSetGlobalPostgreSQLConfiguration(pod *v1.Pod, effectiv
c.logger.Debugf("patching Postgres config via Patroni API on pod %s with following options: %s",
podName, configToSetJson)
if err = c.patroni.SetConfig(pod, configToSet); err != nil {
return true, fmt.Errorf("could not patch postgres parameters within pod %s: %v", podName, err)
return requiresMasterRestart, fmt.Errorf("could not patch postgres parameters with a pod %s: %v", podName, err)
}
return true, nil
return requiresMasterRestart, nil
}
func (c *Cluster) syncSecrets() error {

149
pkg/cluster/sync_test.go
View File

@ -1,22 +1,40 @@
package cluster
import (
"bytes"
"io/ioutil"
"net/http"
"testing"
"time"
"context"
v1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/types"
"github.com/golang/mock/gomock"
"github.com/sirupsen/logrus"
"github.com/stretchr/testify/assert"
"github.com/zalando/postgres-operator/mocks"
acidv1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
fakeacidv1 "github.com/zalando/postgres-operator/pkg/generated/clientset/versioned/fake"
"github.com/zalando/postgres-operator/pkg/util/config"
"github.com/zalando/postgres-operator/pkg/util/k8sutil"
"github.com/zalando/postgres-operator/pkg/util/patroni"
"k8s.io/client-go/kubernetes/fake"
)
var patroniLogger = logrus.New().WithField("test", "patroni")
func newMockPod(ip string) *v1.Pod {
return &v1.Pod{
Status: v1.PodStatus{
PodIP: ip,
},
}
}
func newFakeK8sSyncClient() (k8sutil.KubernetesClient, *fake.Clientset) {
acidClientSet := fakeacidv1.NewSimpleClientset()
clientSet := fake.NewSimpleClientset()
@ -113,3 +131,134 @@ func TestSyncStatefulSetsAnnotations(t *testing.T) {
t.Errorf("%s: inherited annotation not found in desired statefulset: %#v", testName, desiredSts.Annotations)
}
}
func TestCheckAndSetGlobalPostgreSQLConfiguration(t *testing.T) {
testName := "test config comparison"
client, _ := newFakeK8sSyncClient()
clusterName := "acid-test-cluster"
namespace := "default"
ctrl := gomock.NewController(t)
defer ctrl.Finish()
pg := acidv1.Postgresql{
ObjectMeta: metav1.ObjectMeta{
Name: clusterName,
Namespace: namespace,
},
Spec: acidv1.PostgresSpec{
Patroni: acidv1.Patroni{
TTL: 20,
},
PostgresqlParam: acidv1.PostgresqlParam{
Parameters: map[string]string{
"log_min_duration_statement": "200",
"max_connections": "50",
},
},
Volume: acidv1.Volume{
Size: "1Gi",
},
},
}
var cluster = New(
Config{
OpConfig: config.Config{
PodManagementPolicy: "ordered_ready",
Resources: config.Resources{
ClusterLabels: map[string]string{"application": "spilo"},
ClusterNameLabel: "cluster-name",
DefaultCPURequest: "300m",
DefaultCPULimit: "300m",
DefaultMemoryRequest: "300Mi",
DefaultMemoryLimit: "300Mi",
PodRoleLabel: "spilo-role",
ResourceCheckInterval: time.Duration(3),
ResourceCheckTimeout: time.Duration(10),
},
},
}, client, pg, logger, eventRecorder)
// mocking a config after setConfig is called
configJson := `{"postgresql": {"parameters": {"log_min_duration_statement": 200, "max_connections": 50}}}, "ttl": 20}`
r := ioutil.NopCloser(bytes.NewReader([]byte(configJson)))
response := http.Response{
StatusCode: 200,
Body: r,
}
mockClient := mocks.NewMockHTTPClient(ctrl)
mockClient.EXPECT().Do(gomock.Any()).Return(&response, nil).AnyTimes()
p := patroni.New(patroniLogger, mockClient)
cluster.patroni = p
mockPod := newMockPod("192.168.100.1")
// simulate existing config that differs with cluster.Spec
tests := []struct {
subtest string
pod *v1.Pod
patroni acidv1.Patroni
pgParams map[string]string
restartMaster bool
}{
{
subtest: "Patroni and Postgresql.Parameters differ - restart replica first",
pod: mockPod,
patroni: acidv1.Patroni{
TTL: 30, // desired 20
},
pgParams: map[string]string{
"log_min_duration_statement": "500", // desired 200
"max_connections": "100", // desired 50
},
restartMaster: false,
},
{
subtest: "multiple Postgresql.Parameters differ - restart replica first",
pod: mockPod,
patroni: acidv1.Patroni{
TTL: 20,
},
pgParams: map[string]string{
"log_min_duration_statement": "500", // desired 200
"max_connections": "100", // desired 50
},
restartMaster: false,
},
{
subtest: "desired max_connections bigger - restart replica first",
pod: mockPod,
patroni: acidv1.Patroni{
TTL: 20,
},
pgParams: map[string]string{
"log_min_duration_statement": "200",
"max_connections": "30", // desired 50
},
restartMaster: false,
},
{
subtest: "desired max_connections smaller - restart master first",
pod: mockPod,
patroni: acidv1.Patroni{
TTL: 20,
},
pgParams: map[string]string{
"log_min_duration_statement": "200",
"max_connections": "100", // desired 50
},
restartMaster: true,
},
}
for _, tt := range tests {
requireMasterRestart, err := cluster.checkAndSetGlobalPostgreSQLConfiguration(tt.pod, tt.patroni, cluster.Spec.Patroni, tt.pgParams, cluster.Spec.Parameters)
assert.NoError(t, err)
if requireMasterRestart != tt.restartMaster {
t.Errorf("%s - %s: unexpect master restart strategy, got %v, expected %v", testName, tt.subtest, requireMasterRestart, tt.restartMaster)
}
}
}

10
pkg/util/patroni/patroni.go
View File

@ -238,16 +238,12 @@ func (p *Patroni) Restart(server *v1.Pod) error {
if err != nil {
return err
}
memberData, err := p.GetMemberData(server)
if err != nil {
if err := p.httpPostOrPatch(http.MethodPost, apiURLString+restartPath, buf); err != nil {
return err
}
p.logger.Infof("Postgres server successfuly restarted in pod %s", server.Name)
// do restart only when it is pending
if !memberData.PendingRestart {
return nil
}
return p.httpPostOrPatch(http.MethodPost, apiURLString+restartPath, buf)
return nil
}
// GetMemberData read member data from patroni API