refactor httpGet in Patroni and extend unit tests

pkg/util/patroni/patroni.go

@@ -111,28 +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
 }
 
@@ -196,37 +191,16 @@ type MemberData struct {
 	Patroni         MemberDataPatroni `json:"patroni"`
 }
 
-func (p *Patroni) GetConfigOrStatus(server *v1.Pod, path string) (string, error) {
-	apiURLString, err := apiURL(server)
-	if err != nil {
-		return "", err
-	}
-	result, err := p.httpGet(apiURLString + path)
-	if err != nil {
-		return "", err
-	}
-	return result, nil
-}
-
-func (p *Patroni) GetStatus(server *v1.Pod) (map[string]interface{}, error) {
-	result := make(map[string]interface{})
-	body, err := p.GetConfigOrStatus(server, statusPath)
-	if err != nil {
-		return result, err
-	}
-	err = json.Unmarshal([]byte(body), &result)
-	if err != nil {
-		return result, err
-	}
-	return result, err
-}
-
 func (p *Patroni) GetConfig(server *v1.Pod) (acidv1.Patroni, map[string]string, error) {
 	var (
 		patroniConfig acidv1.Patroni
 		pgConfig      map[string]interface{}
 	)
-	body, err := p.GetConfigOrStatus(server, configPath)
+	apiURLString, err := apiURL(server)
+	if err != nil {
+		return patroniConfig, nil, err
+	}
+	body, err := p.httpGet(apiURLString + configPath)
 	if err != nil {
 		return patroniConfig, nil, err
 	}
@@ -264,9 +238,9 @@ func (p *Patroni) Restart(server *v1.Pod) error {
 	if err != nil {
 		return err
 	}
-	status, _ := p.GetStatus(server)
+	memberData, _ := p.GetMemberData(server)
-	pending_restart, ok := status["pending_restart"]
+
-	if !ok || !pending_restart.(bool) {
+	if !memberData.PendingRestart {
 		return nil
 	}
 	return p.httpPostOrPatch(http.MethodPost, apiURLString+restartPath, buf)
@@ -279,19 +253,13 @@ 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)
 	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{
@@ -84,27 +89,118 @@ func TestPatroniAPI(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{
 		Status: v1.PodStatus{
 			PodIP: "192.168.100.1",
 		},
 	}
-	_, err := p.GetMemberData(&pod)
+	memberData, err := p.GetMemberData(&pod)
+
+	if !reflect.DeepEqual(expectedMemberData, memberData) {
+		t.Errorf("Patroni member data differs: expected: %#v, got: %#v", expectedMemberData, memberData)
+	}
 
 	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)
+
+	pod := v1.Pod{
+		Status: v1.PodStatus{
+			PodIP: "192.168.100.1",
+		},
+	}
+	patroniConfig, pgParameters, err := p.GetConfig(&pod)
+	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)
+	}
+}