improve Patroni config sync (#1635)

* improve Patroni config sync
* collect new and updated slots to patch patroni
* refactor httpGet in Patroni and extend unit tests
* GetMemberData should call the patroni endpoint
* add PATCH test

e2e/tests/test_e2e.py

@@ -1099,19 +1099,19 @@ class EndToEndTestCase(unittest.TestCase):
 
             def compare_config():
                 effective_config = k8s.patroni_rest(masterPod.metadata.name, "config")
-                desired_patroni = pg_patch_config["spec"]["patroni"]
+                desired_config = pg_patch_config["spec"]["patroni"]
                 desired_parameters = pg_patch_config["spec"]["postgresql"]["parameters"]
                 effective_parameters = effective_config["postgresql"]["parameters"]
                 self.assertEqual(desired_parameters["max_connections"], effective_parameters["max_connections"],
                             "max_connections not updated")
                 self.assertTrue(effective_config["slots"] is not None, "physical replication slot not added")
-                self.assertEqual(desired_patroni["ttl"], effective_config["ttl"],
+                self.assertEqual(desired_config["ttl"], effective_config["ttl"],
                             "ttl not updated")
-                self.assertEqual(desired_patroni["loop_wait"], effective_config["loop_wait"],
+                self.assertEqual(desired_config["loop_wait"], effective_config["loop_wait"],
                             "loop_wait not updated")
-                self.assertEqual(desired_patroni["retry_timeout"], effective_config["retry_timeout"],
+                self.assertEqual(desired_config["retry_timeout"], effective_config["retry_timeout"],
                             "retry_timeout not updated")
-                self.assertEqual(desired_patroni["synchronous_mode"], effective_config["synchronous_mode"],
+                self.assertEqual(desired_config["synchronous_mode"], effective_config["synchronous_mode"],
                             "synchronous_mode not updated")
                 return True
 

pkg/cluster/k8sres.go

@@ -30,13 +30,12 @@ import (
 )
 
 const (
-	pgBinariesLocationTemplate       = "/usr/lib/postgresql/%v/bin"
+	pgBinariesLocationTemplate     = "/usr/lib/postgresql/%v/bin"
-	patroniPGBinariesParameterName   = "bin_dir"
+	patroniPGBinariesParameterName = "bin_dir"
-	patroniPGParametersParameterName = "parameters"
+	patroniPGHBAConfParameterName  = "pg_hba"
-	patroniPGHBAConfParameterName    = "pg_hba"
+	localHost                      = "127.0.0.1/32"
-	localHost                        = "127.0.0.1/32"
+	connectionPoolerContainer      = "connection-pooler"
-	connectionPoolerContainer        = "connection-pooler"
+	pgPort                         = 5432
-	pgPort                           = 5432
 )
 
 type pgUser struct {
@@ -277,11 +276,11 @@ PatroniInitDBParams:
 		local, bootstrap := getLocalAndBoostrapPostgreSQLParameters(pg.Parameters)
 
 		if len(local) > 0 {
-			config.PgLocalConfiguration[patroniPGParametersParameterName] = local
+			config.PgLocalConfiguration[constants.PatroniPGParametersParameterName] = local
 		}
 		if len(bootstrap) > 0 {
 			config.Bootstrap.DCS.PGBootstrapConfiguration = make(map[string]interface{})
-			config.Bootstrap.DCS.PGBootstrapConfiguration[patroniPGParametersParameterName] = bootstrap
+			config.Bootstrap.DCS.PGBootstrapConfiguration[constants.PatroniPGParametersParameterName] = bootstrap
 		}
 	}
 	// Patroni gives us a choice of writing pg_hba.conf to either the bootstrap section or to the local postgresql one.

pkg/cluster/sync.go

@@ -395,18 +395,24 @@ func (c *Cluster) syncStatefulSet() error {
 	// get Postgres config, compare with manifest and update via Patroni PATCH endpoint if it differs
 	// Patroni's config endpoint is just a "proxy" to DCS. It is enough to patch it only once and it doesn't matter which pod is used.
 	for i, pod := range pods {
+		emptyPatroniConfig := acidv1.Patroni{}
 		podName := util.NameFromMeta(pods[i].ObjectMeta)
-		config, err := c.patroni.GetConfig(&pod)
+		patroniConfig, pgParameters, err := c.patroni.GetConfig(&pod)
 		if err != nil {
 			c.logger.Warningf("could not get Postgres config from pod %s: %v", podName, err)
 			continue
 		}
-		instanceRestartRequired, err = c.checkAndSetGlobalPostgreSQLConfiguration(&pod, config)
+
-		if err != nil {
+		// empty config probably means cluster is not fully initialized yet, e.g. restoring from backup
-			c.logger.Warningf("could not set PostgreSQL configuration options for pod %s: %v", podName, err)
+		// do not attempt a restart
-			continue
+		if !reflect.DeepEqual(patroniConfig, emptyPatroniConfig) || len(pgParameters) > 0 {
+			instanceRestartRequired, err = c.checkAndSetGlobalPostgreSQLConfiguration(&pod, patroniConfig, pgParameters)
+			if err != nil {
+				c.logger.Warningf("could not set PostgreSQL configuration options for pod %s: %v", podName, err)
+				continue
+			}
+			break
 		}
-		break
 	}
 
 	// if the config update requires a restart, call Patroni restart for replicas first, then master
@@ -493,16 +499,9 @@ func (c *Cluster) AnnotationsToPropagate(annotations map[string]string) map[stri
 
 // checkAndSetGlobalPostgreSQLConfiguration checks whether cluster-wide API parameters
 // (like max_connections) have changed and if necessary sets it via the Patroni API
-func (c *Cluster) checkAndSetGlobalPostgreSQLConfiguration(pod *v1.Pod, patroniConfig map[string]interface{}) (bool, error) {
+func (c *Cluster) checkAndSetGlobalPostgreSQLConfiguration(pod *v1.Pod, patroniConfig acidv1.Patroni, effectivePgParameters map[string]string) (bool, error) {
 	configToSet := make(map[string]interface{})
 	parametersToSet := make(map[string]string)
-	effectivePgParameters := make(map[string]interface{})
-
-	// read effective Patroni config if set
-	if patroniConfig != nil {
-		effectivePostgresql := patroniConfig["postgresql"].(map[string]interface{})
-		effectivePgParameters = effectivePostgresql[patroniPGParametersParameterName].(map[string]interface{})
-	}
 
 	// compare parameters under postgresql section with c.Spec.Postgresql.Parameters from manifest
 	desiredPgParameters := c.Spec.Parameters
@@ -514,36 +513,47 @@ func (c *Cluster) checkAndSetGlobalPostgreSQLConfiguration(pod *v1.Pod, patroniC
 	}
 
 	if len(parametersToSet) > 0 {
-		configToSet["postgresql"] = map[string]interface{}{patroniPGParametersParameterName: parametersToSet}
+		configToSet["postgresql"] = map[string]interface{}{constants.PatroniPGParametersParameterName: parametersToSet}
 	}
 
 	// compare other options from config with c.Spec.Patroni from manifest
 	desiredPatroniConfig := c.Spec.Patroni
-	if desiredPatroniConfig.LoopWait > 0 && desiredPatroniConfig.LoopWait != uint32(patroniConfig["loop_wait"].(float64)) {
+	if desiredPatroniConfig.LoopWait > 0 && desiredPatroniConfig.LoopWait != patroniConfig.LoopWait {
 		configToSet["loop_wait"] = desiredPatroniConfig.LoopWait
 	}
-	if desiredPatroniConfig.MaximumLagOnFailover > 0 && desiredPatroniConfig.MaximumLagOnFailover != float32(patroniConfig["maximum_lag_on_failover"].(float64)) {
+	if desiredPatroniConfig.MaximumLagOnFailover > 0 && desiredPatroniConfig.MaximumLagOnFailover != patroniConfig.MaximumLagOnFailover {
 		configToSet["maximum_lag_on_failover"] = desiredPatroniConfig.MaximumLagOnFailover
 	}
-	if desiredPatroniConfig.PgHba != nil && !reflect.DeepEqual(desiredPatroniConfig.PgHba, (patroniConfig["pg_hba"])) {
+	if desiredPatroniConfig.PgHba != nil && !reflect.DeepEqual(desiredPatroniConfig.PgHba, patroniConfig.PgHba) {
 		configToSet["pg_hba"] = desiredPatroniConfig.PgHba
 	}
-	if desiredPatroniConfig.RetryTimeout > 0 && desiredPatroniConfig.RetryTimeout != uint32(patroniConfig["retry_timeout"].(float64)) {
+	if desiredPatroniConfig.RetryTimeout > 0 && desiredPatroniConfig.RetryTimeout != patroniConfig.RetryTimeout {
 		configToSet["retry_timeout"] = desiredPatroniConfig.RetryTimeout
 	}
-	if desiredPatroniConfig.Slots != nil && !reflect.DeepEqual(desiredPatroniConfig.Slots, patroniConfig["slots"]) {
+	if desiredPatroniConfig.SynchronousMode != patroniConfig.SynchronousMode {
-		configToSet["slots"] = desiredPatroniConfig.Slots
-	}
-	if desiredPatroniConfig.SynchronousMode != patroniConfig["synchronous_mode"] {
 		configToSet["synchronous_mode"] = desiredPatroniConfig.SynchronousMode
 	}
-	if desiredPatroniConfig.SynchronousModeStrict != patroniConfig["synchronous_mode_strict"] {
+	if desiredPatroniConfig.SynchronousModeStrict != patroniConfig.SynchronousModeStrict {
 		configToSet["synchronous_mode_strict"] = desiredPatroniConfig.SynchronousModeStrict
 	}
-	if desiredPatroniConfig.TTL > 0 && desiredPatroniConfig.TTL != uint32(patroniConfig["ttl"].(float64)) {
+	if desiredPatroniConfig.TTL > 0 && desiredPatroniConfig.TTL != patroniConfig.TTL {
 		configToSet["ttl"] = desiredPatroniConfig.TTL
 	}
 
+	// check if specified slots exist in config and if they differ
+	slotsToSet := make(map[string]map[string]string)
+	for slotName, desiredSlot := range desiredPatroniConfig.Slots {
+		if effectiveSlot, exists := patroniConfig.Slots[slotName]; exists {
+			if reflect.DeepEqual(desiredSlot, effectiveSlot) {
+				continue
+			}
+		}
+		slotsToSet[slotName] = desiredSlot
+	}
+	if len(slotsToSet) > 0 {
+		configToSet["slots"] = slotsToSet
+	}
+
 	if len(configToSet) == 0 {
 		return false, nil
 	}

pkg/util/constants/postgresql.go

@@ -8,6 +8,8 @@ const (
 	PostgresDataMount = "/home/postgres/pgdata"
 	PostgresDataPath  = PostgresDataMount + "/pgroot"
 
+	PatroniPGParametersParameterName = "parameters"
+
 	PostgresConnectRetryTimeout = 2 * time.Minute
 	PostgresConnectTimeout      = 15 * time.Second
 

pkg/util/patroni/patroni.go

@@ -10,9 +10,11 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/zalando/postgres-operator/pkg/util/constants"
 	httpclient "github.com/zalando/postgres-operator/pkg/util/httpclient"
 
 	"github.com/sirupsen/logrus"
+	acidv1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
 	v1 "k8s.io/api/core/v1"
 )
 
@@ -31,7 +33,7 @@ type Interface interface {
 	SetPostgresParameters(server *v1.Pod, options map[string]string) error
 	GetMemberData(server *v1.Pod) (MemberData, error)
 	Restart(server *v1.Pod) error
-	GetConfig(server *v1.Pod) (map[string]interface{}, error)
+	GetConfig(server *v1.Pod) (acidv1.Patroni, map[string]string, error)
 	SetConfig(server *v1.Pod, config map[string]interface{}) error
 }
 
@@ -109,28 +111,23 @@ func (p *Patroni) httpPostOrPatch(method string, url string, body *bytes.Buffer)
 }
 
 func (p *Patroni) httpGet(url string) (string, error) {
-	request, err := http.NewRequest("GET", url, nil)
+	p.logger.Debugf("making GET http request: %s", url)
-	if err != nil {
-		return "", fmt.Errorf("could not create request: %v", err)
-	}
 
-	p.logger.Debugf("making GET http request: %s", request.URL.String())
+	response, err := p.httpClient.Get(url)
-
-	resp, err := p.httpClient.Do(request)
 	if err != nil {
 		return "", fmt.Errorf("could not make request: %v", err)
 	}
-	bodyBytes, err := ioutil.ReadAll(resp.Body)
+	defer response.Body.Close()
+
+	bodyBytes, err := ioutil.ReadAll(response.Body)
 	if err != nil {
 		return "", fmt.Errorf("could not read response: %v", err)
 	}
-	if err := resp.Body.Close(); err != nil {
+
-		return "", fmt.Errorf("could not close request: %v", err)
+	if response.StatusCode != http.StatusOK {
+		return string(bodyBytes), fmt.Errorf("patroni returned '%d'", response.StatusCode)
 	}
 
-	if resp.StatusCode != http.StatusOK {
-		return string(bodyBytes), fmt.Errorf("patroni returned '%d'", resp.StatusCode)
-	}
 	return string(bodyBytes), nil
 }
 
@@ -194,30 +191,43 @@ type MemberData struct {
 	Patroni         MemberDataPatroni `json:"patroni"`
 }
 
-func (p *Patroni) GetConfigOrStatus(server *v1.Pod, path string) (map[string]interface{}, error) {
+func (p *Patroni) GetConfig(server *v1.Pod) (acidv1.Patroni, map[string]string, error) {
-	result := make(map[string]interface{})
+	var (
+		patroniConfig acidv1.Patroni
+		pgConfig      map[string]interface{}
+	)
 	apiURLString, err := apiURL(server)
 	if err != nil {
-		return result, err
+		return patroniConfig, nil, err
 	}
-	body, err := p.httpGet(apiURLString + path)
+	body, err := p.httpGet(apiURLString + configPath)
-	err = json.Unmarshal([]byte(body), &result)
 	if err != nil {
-		return result, err
+		return patroniConfig, nil, err
+	}
+	err = json.Unmarshal([]byte(body), &patroniConfig)
+	if err != nil {
+		return patroniConfig, nil, err
 	}
 
-	return result, err
+	// unmarshalling postgresql parameters needs a detour
+	err = json.Unmarshal([]byte(body), &pgConfig)
+	if err != nil {
+		return patroniConfig, nil, err
+	}
+	pgParameters := make(map[string]string)
+	if _, exists := pgConfig["postgresql"]; exists {
+		effectivePostgresql := pgConfig["postgresql"].(map[string]interface{})
+		effectivePgParameters := effectivePostgresql[constants.PatroniPGParametersParameterName].(map[string]interface{})
+		for parameter, value := range effectivePgParameters {
+			strValue := fmt.Sprintf("%v", value)
+			pgParameters[parameter] = strValue
+		}
+	}
+
+	return patroniConfig, pgParameters, err
 }
 
-func (p *Patroni) GetStatus(server *v1.Pod) (map[string]interface{}, error) {
+// Restart method restarts instance via Patroni POST API call.
-	return p.GetConfigOrStatus(server, statusPath)
-}
-
-func (p *Patroni) GetConfig(server *v1.Pod) (map[string]interface{}, error) {
-	return p.GetConfigOrStatus(server, configPath)
-}
-
-//Restart method restarts instance via Patroni POST API call.
 func (p *Patroni) Restart(server *v1.Pod) error {
 	buf := &bytes.Buffer{}
 	err := json.NewEncoder(buf).Encode(map[string]interface{}{"restart_pending": true})
@@ -228,9 +238,13 @@ func (p *Patroni) Restart(server *v1.Pod) error {
 	if err != nil {
 		return err
 	}
-	status, err := p.GetStatus(server)
+	memberData, err := p.GetMemberData(server)
-	pending_restart, ok := status["pending_restart"]
+	if err != nil {
-	if !ok || !pending_restart.(bool) {
+		return err
+	}
+
+	// do restart only when it is pending
+	if !memberData.PendingRestart {
 		return nil
 	}
 	return p.httpPostOrPatch(http.MethodPost, apiURLString+restartPath, buf)
@@ -243,19 +257,13 @@ func (p *Patroni) GetMemberData(server *v1.Pod) (MemberData, error) {
 	if err != nil {
 		return MemberData{}, err
 	}
-	response, err := p.httpClient.Get(apiURLString)
+	body, err := p.httpGet(apiURLString + statusPath)
 	if err != nil {
-		return MemberData{}, fmt.Errorf("could not perform Get request: %v", err)
+		return MemberData{}, err
-	}
-	defer response.Body.Close()
-
-	body, err := ioutil.ReadAll(response.Body)
-	if err != nil {
-		return MemberData{}, fmt.Errorf("could not read response: %v", err)
 	}
 
 	data := MemberData{}
-	err = json.Unmarshal(body, &data)
+	err = json.Unmarshal([]byte(body), &data)
 	if err != nil {
 		return MemberData{}, err
 	}

pkg/util/patroni/patroni_test.go

@@ -6,14 +6,19 @@ import (
 	"fmt"
 	"io/ioutil"
 	"net/http"
+	"reflect"
 	"testing"
 
 	"github.com/golang/mock/gomock"
+	"github.com/sirupsen/logrus"
 	"github.com/zalando/postgres-operator/mocks"
 
+	acidv1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
 	v1 "k8s.io/api/core/v1"
 )
 
+var logger = logrus.New().WithField("test", "patroni")
+
 func newMockPod(ip string) *v1.Pod {
 	return &v1.Pod{
 		Status: v1.PodStatus{
@@ -80,31 +85,141 @@ func TestApiURL(t *testing.T) {
 	}
 }
 
-func TestPatroniAPI(t *testing.T) {
+func TestGetMemberData(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	defer ctrl.Finish()
 
-	json := `{"state": "running", "postmaster_start_time": "2021-02-19 14:31:50.053 CET", "role": "master", "server_version": 90621, "cluster_unlocked": false, "xlog": {"location": 55978296057856}, "timeline": 6, "database_system_identifier": "6462555844314089962", "pending_restart": true, "patroni": {"version": "2.0.1", "scope": "acid-rest92-standby"}}`
+	expectedMemberData := MemberData{
+		State:          "running",
+		Role:           "master",
+		ServerVersion:  130004,
+		PendingRestart: true,
+		Patroni: MemberDataPatroni{
+			Version: "2.1.1",
+			Scope:   "acid-test-cluster",
+		},
+	}
+
+	json := `{"state": "running", "postmaster_start_time": "2021-02-19 14:31:50.053 CET", "role": "master", "server_version": 130004, "cluster_unlocked": false, "xlog": {"location": 123456789}, "timeline": 1, "database_system_identifier": "6462555844314089962", "pending_restart": true, "patroni": {"version": "2.1.1", "scope": "acid-test-cluster"}}`
 	r := ioutil.NopCloser(bytes.NewReader([]byte(json)))
 
 	response := http.Response{
-		Status: "200",
+		StatusCode: 200,
-		Body:   r,
+		Body:       r,
 	}
 
 	mockClient := mocks.NewMockHTTPClient(ctrl)
 	mockClient.EXPECT().Get(gomock.Any()).Return(&response, nil)
 
-	p := New(nil, mockClient)
+	p := New(logger, mockClient)
 
-	pod := v1.Pod{
+	memberData, err := p.GetMemberData(newMockPod("192.168.100.1"))
-		Status: v1.PodStatus{
+
-			PodIP: "192.168.100.1",
+	if !reflect.DeepEqual(expectedMemberData, memberData) {
-		},
+		t.Errorf("Patroni member data differs: expected: %#v, got: %#v", expectedMemberData, memberData)
 	}
-	_, err := p.GetMemberData(&pod)
 
 	if err != nil {
 		t.Errorf("Could not read Patroni data: %v", err)
 	}
 }
+
+func TestGetConfig(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	expectedPatroniConfig := acidv1.Patroni{
+		TTL:                  30,
+		LoopWait:             10,
+		RetryTimeout:         10,
+		MaximumLagOnFailover: 33554432,
+		Slots: map[string]map[string]string{
+			"cdc": {
+				"database": "foo",
+				"plugin":   "wal2json",
+				"type":     "logical",
+			},
+		},
+	}
+
+	expectedPgParameters := map[string]string{
+		"archive_mode":                    "on",
+		"archive_timeout":                 "1800s",
+		"autovacuum_analyze_scale_factor": "0.02",
+		"autovacuum_max_workers":          "5",
+		"autovacuum_vacuum_scale_factor":  "0.05",
+		"checkpoint_completion_target":    "0.9",
+		"hot_standby":                     "on",
+		"log_autovacuum_min_duration":     "0",
+		"log_checkpoints":                 "on",
+		"log_connections":                 "on",
+		"log_disconnections":              "on",
+		"log_line_prefix":                 "%t [%p]: [%l-1] %c %x %d %u %a %h ",
+		"log_lock_waits":                  "on",
+		"log_min_duration_statement":      "500",
+		"log_statement":                   "ddl",
+		"log_temp_files":                  "0",
+		"max_connections":                 "100",
+		"max_replication_slots":           "10",
+		"max_wal_senders":                 "10",
+		"tcp_keepalives_idle":             "900",
+		"tcp_keepalives_interval":         "100",
+		"track_functions":                 "all",
+		"wal_level":                       "hot_standby",
+		"wal_log_hints":                   "on",
+	}
+
+	configJson := `{"loop_wait": 10, "maximum_lag_on_failover": 33554432, "postgresql": {"parameters": {"archive_mode": "on", "archive_timeout": "1800s", "autovacuum_analyze_scale_factor": 0.02, "autovacuum_max_workers": 5, "autovacuum_vacuum_scale_factor": 0.05, "checkpoint_completion_target": 0.9, "hot_standby": "on", "log_autovacuum_min_duration": 0, "log_checkpoints": "on", "log_connections": "on", "log_disconnections": "on", "log_line_prefix": "%t [%p]: [%l-1] %c %x %d %u %a %h ", "log_lock_waits": "on", "log_min_duration_statement": 500, "log_statement": "ddl", "log_temp_files": 0, "max_connections": 100, "max_replication_slots": 10, "max_wal_senders": 10, "tcp_keepalives_idle": 900, "tcp_keepalives_interval": 100, "track_functions": "all", "wal_level": "hot_standby", "wal_log_hints": "on"}, "use_pg_rewind": true, "use_slots": true}, "retry_timeout": 10, "slots": {"cdc": {"database": "foo", "plugin": "wal2json", "type": "logical"}}, "ttl": 30}`
+	r := ioutil.NopCloser(bytes.NewReader([]byte(configJson)))
+
+	response := http.Response{
+		StatusCode: 200,
+		Body:       r,
+	}
+
+	mockClient := mocks.NewMockHTTPClient(ctrl)
+	mockClient.EXPECT().Get(gomock.Any()).Return(&response, nil)
+
+	p := New(logger, mockClient)
+
+	patroniConfig, pgParameters, err := p.GetConfig(newMockPod("192.168.100.1"))
+	if err != nil {
+		t.Errorf("Could not read Patroni config endpoint: %v", err)
+	}
+
+	if !reflect.DeepEqual(expectedPatroniConfig, patroniConfig) {
+		t.Errorf("Patroni config differs: expected: %#v, got: %#v", expectedPatroniConfig, patroniConfig)
+	}
+	if !reflect.DeepEqual(expectedPgParameters, pgParameters) {
+		t.Errorf("Postgre parameters differ: expected: %#v, got: %#v", expectedPgParameters, pgParameters)
+	}
+}
+
+func TestSetPostgresParameters(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	parametersToSet := map[string]string{
+		"max_connections": "50",
+		"wal_level":       "logical",
+	}
+
+	configJson := `{"loop_wait": 10, "maximum_lag_on_failover": 33554432, "postgresql": {"parameters": {"archive_mode": "on", "archive_timeout": "1800s", "autovacuum_analyze_scale_factor": 0.02, "autovacuum_max_workers": 5, "autovacuum_vacuum_scale_factor": 0.05, "checkpoint_completion_target": 0.9, "hot_standby": "on", "log_autovacuum_min_duration": 0, "log_checkpoints": "on", "log_connections": "on", "log_disconnections": "on", "log_line_prefix": "%t [%p]: [%l-1] %c %x %d %u %a %h ", "log_lock_waits": "on", "log_min_duration_statement": 500, "log_statement": "ddl", "log_temp_files": 0, "max_connections": 50, "max_replication_slots": 10, "max_wal_senders": 10, "tcp_keepalives_idle": 900, "tcp_keepalives_interval": 100, "track_functions": "all", "wal_level": "logical", "wal_log_hints": "on"}, "use_pg_rewind": true, "use_slots": true}, "retry_timeout": 10, "slots": {"cdc": {"database": "foo", "plugin": "wal2json", "type": "logical"}}, "ttl": 30}`
+	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)
+
+	p := New(logger, mockClient)
+
+	err := p.SetPostgresParameters(newMockPod("192.168.100.1"), parametersToSet)
+	if err != nil {
+		t.Errorf("could not call patch Patroni config: %v", err)
+	}
+
+}