WIP: Add ability to define custom entries in pg_ident.conf

cmd/keeper/cmd/keeper.go

@@ -1058,6 +1058,7 @@ func (p *PostgresKeeper) postgresKeeperSM(pctx context.Context) {
 
 	// Generate hba auth from clusterData
 	pgm.SetHba(p.generateHBA(cd, db, p.waitSyncStandbysSynced))
+	pgm.SetIdent(db.Spec.PgIdent)
 
 	var pgParameters common.Parameters
 
@@ -1475,6 +1476,7 @@ func (p *PostgresKeeper) postgresKeeperSM(pctx context.Context) {
 				p.waitSyncStandbysSynced = true
 				log.Infow("not allowing connection as normal users since synchronous replication is enabled and instance was down")
 				pgm.SetHba(p.generateHBA(cd, db, true))
+				pgm.SetIdent(db.Spec.PgIdent)
 			}
 
 			if err = pgm.Start(); err != nil {
@@ -1657,6 +1659,15 @@ func (p *PostgresKeeper) postgresKeeperSM(pctx context.Context) {
 		// for tests
 		log.Infow("postgres hba entries not changed")
 	}
+	newIdent := db.Spec.PgIdent
+	if !reflect.DeepEqual(newIdent, pgm.CurIdent()) {
+		log.Infow("postgres ident entries changed, reloading postgres instance")
+		pgm.SetIdent(newIdent)
+		needsReload = true
+	} else {
+		// for tests
+		log.Infow("postgres ident entries not changed")
+	}
 
 	if needsReload {
 		needsReloadGauge.Set(1) // mark as reload needed

cmd/sentinel/cmd/sentinel.go

@@ -381,6 +381,7 @@ func (s *Sentinel) setDBSpecFromClusterSpec(cd *cluster.ClusterData) {
 		db.Spec.UsePgrewind = *clusterSpec.UsePgrewind
 		db.Spec.PGParameters = clusterSpec.PGParameters
 		db.Spec.PGHBA = clusterSpec.PGHBA
+		db.Spec.PgIdent = clusterSpec.PgIdent
 		if db.Spec.FollowConfig != nil && db.Spec.FollowConfig.Type == cluster.FollowTypeExternal {
 			db.Spec.FollowConfig.StandbySettings = clusterSpec.StandbyConfig.StandbySettings
 			db.Spec.FollowConfig.ArchiveRecoverySettings = clusterSpec.StandbyConfig.ArchiveRecoverySettings

cmd/stolonctl/cmd/spec.go

@@ -19,6 +19,7 @@ import (
 
 	cmdcommon "github.com/sorintlab/stolon/cmd"
 	"github.com/sorintlab/stolon/internal/cluster"
+	"github.com/sorintlab/stolon/internal/postgresql"
 
 	"github.com/spf13/cobra"
 )
@@ -69,6 +70,7 @@ type ClusterSpecNoDefaults struct {
 	DefaultSUReplAccessMode          *cluster.SUReplAccessMode `json:"defaultSUReplAccessMode,omitempty"`
 	PGParameters                     cluster.PGParameters      `json:"pgParameters,omitempty"`
 	PGHBA                            []string                  `json:"pgHBA,omitempty"`
+	PgIdent                          postgresql.PgIdent        `json:"pgIdent"`
 	AutomaticPgRestart               *bool                     `json:"automaticPgRestart,omitempty"`
 }
 
@@ -100,6 +102,7 @@ type ClusterSpecDefaults struct {
 	DefaultSUReplAccessMode          *cluster.SUReplAccessMode `json:"defaultSUReplAccessMode"`
 	PGParameters                     cluster.PGParameters      `json:"pgParameters"`
 	PGHBA                            []string                  `json:"pgHBA"`
+	PgIdent                          postgresql.PgIdent        `json:"pgIdent"`
 	AutomaticPgRestart               *bool                     `json:"automaticPgRestart"`
 }
 

internal/cluster/cluster.go

@@ -286,6 +286,8 @@ type ClusterSpec struct {
 	// Additional pg_hba.conf entries
 	// we don't set omitempty since we want to distinguish between null or empty slice
 	PGHBA []string `json:"pgHBA"`
+	// pg_ident.conf entries
+	PgIdent util.PgIdent `json:"pgIdent"`
 	// Enable automatic pg restart when pg parameters that requires restart changes
 	AutomaticPgRestart *bool `json:"automaticPgRestart"`
 }
@@ -625,6 +627,8 @@ type DBSpec struct {
 	// Additional pg_hba.conf entries
 	// We don't set omitempty since we want to distinguish between null or empty slice
 	PGHBA []string `json:"pgHBA"`
+	// pg_ident.conf entries
+	PgIdent util.PgIdent `json:"pgIdent"`
 	// DB Role (master or standby)
 	Role common.Role `json:"role,omitempty"`
 	// FollowConfig when Role is "standby"

internal/postgresql/postgresql.go

@@ -59,6 +59,13 @@ var (
 
 var log = slog.S()
 
+type PgIdent map[string][]UserMaps
+
+type UserMaps struct {
+	SystemUsername string `json:"systemUsername"`
+	DBUsername     string `json:"databaseUsername"`
+}
+
 type PGManager interface {
 	GetTimelinesHistory(timeline uint64) ([]*TimelineHistory, error)
 }
@@ -69,6 +76,8 @@ type Manager struct {
 	parameters         common.Parameters
 	recoveryOptions    *RecoveryOptions
 	hba                []string
+	ident              PgIdent
+	currentIdent       PgIdent
 	curParameters      common.Parameters
 	curRecoveryOptions *RecoveryOptions
 	curHba             []string
@@ -178,10 +187,18 @@ func (p *Manager) SetHba(hba []string) {
 	p.hba = hba
 }
 
+func (p *Manager) SetIdent(ident PgIdent) {
+	p.ident = ident
+}
+
 func (p *Manager) CurHba() []string {
 	return p.curHba
 }
 
+func (p *Manager) CurIdent() PgIdent {
+	return p.currentIdent
+}
+
 func (p *Manager) UpdateCurParameters() {
 	n, err := copystructure.Copy(p.parameters)
 	if err != nil {
@@ -202,6 +219,14 @@ func (p *Manager) UpdateCurHba() {
 	p.curHba = n.([]string)
 }
 
+func (p *Manager) UpdateCurIdent() {
+	n, err := copystructure.Copy(p.ident)
+	if err != nil {
+		panic(err)
+	}
+	p.currentIdent = n.(PgIdent)
+}
+
 func (p *Manager) Init(initConfig *InitConfig) error {
 	// ioutil.Tempfile already creates files with 0600 permissions
 	pwfile, err := ioutil.TempFile("", "pwfile")
@@ -374,6 +399,7 @@ func (p *Manager) start(args ...string) error {
 	p.UpdateCurParameters()
 	p.UpdateCurRecoveryOptions()
 	p.UpdateCurHba()
+	p.UpdateCurIdent()
 
 	return nil
 }
@@ -438,6 +464,7 @@ func (p *Manager) Reload() error {
 	p.UpdateCurParameters()
 	p.UpdateCurRecoveryOptions()
 	p.UpdateCurHba()
+	p.UpdateCurIdent()
 
 	return nil
 }
@@ -767,6 +794,9 @@ func (p *Manager) writeConfs(useTmpPostgresConf bool) error {
 			return fmt.Errorf("error writing %s file: %v", postgresRecoverySignal, err)
 		}
 	}
+	if err := p.writePgIdent(); err != nil {
+		return fmt.Errorf("error writing pg_ident.conf file: %v", err)
+	}
 	return nil
 }
 
@@ -877,6 +907,25 @@ func (p *Manager) writePgHba() error {
 		})
 }
 
+func (p *Manager) writePgIdent() error {
+	return common.WriteFileAtomicFunc(filepath.Join(p.dataDir, "pg_ident.conf"), 0600,
+		func(f io.Writer) error {
+			if p.ident != nil && len(p.ident) > 0 {
+				if _, err := f.Write([]byte("# MAPNAME\tSYSTEM-USERNAME\tPG-USERNAME" + "\n")); err != nil {
+					return err
+				}
+				for key, value := range p.ident {
+					for _, v := range value {
+						if _, err := f.Write([]byte(fmt.Sprintf("%s\t%s\t%s", key, v.SystemUsername, v.DBUsername) + "\n")); err != nil {
+							return err
+						}
+					}
+				}
+			}
+			return nil
+		})
+}
+
 // createPostgresqlAutoConf creates postgresql.auto.conf as a symlink to
 // /dev/null to block alter systems commands (they'll return an error)
 func (p *Manager) createPostgresqlAutoConf() error {