make encoding configurable in initdb

config.go

@@ -19,6 +19,7 @@ type Config struct {
 	dataPath            string
 	binariesPath        string
 	locale              string
+	encoding            string
 	startParameters     map[string]string
 	binaryRepositoryURL string
 	startTimeout        time.Duration
@@ -110,6 +111,12 @@ func (c Config) Locale(locale string) Config {
 	return c
 }
 
+// Encoding sets the default character set for initdb
+func (c Config) Encoding(encoding string) Config {
+	c.encoding = encoding
+	return c
+}
+
 // StartParameters sets run-time parameters when starting Postgres (passed to Postgres via "-c").
 //
 // These parameters can be used to override the default configuration values in postgres.conf such

embedded_postgres.go

@@ -167,7 +167,7 @@ func (ep *EmbeddedPostgres) cleanDataDirectoryAndInit() error {
 		return fmt.Errorf("unable to clean up data directory %s with error: %s", ep.config.dataPath, err)
 	}
 
-	if err := ep.initDatabase(ep.config.binariesPath, ep.config.runtimePath, ep.config.dataPath, ep.config.username, ep.config.password, ep.config.locale, ep.syncedLogger.file); err != nil {
+	if err := ep.initDatabase(ep.config.binariesPath, ep.config.runtimePath, ep.config.dataPath, ep.config.username, ep.config.password, ep.config.locale, ep.config.encoding, ep.syncedLogger.file); err != nil {
 		return err
 	}
 

embedded_postgres_test.go

@@ -123,7 +123,7 @@ func Test_ErrorWhenUnableToInitDatabase(t *testing.T) {
 		return jarFile, true
 	}
 
-	database.initDatabase = func(binaryExtractLocation, runtimePath, dataLocation, username, password, locale string, logger *os.File) error {
+	database.initDatabase = func(binaryExtractLocation, runtimePath, dataLocation, username, password, locale string, encoding string, logger *os.File) error {
 		return errors.New("ah it did not work")
 	}
 
@@ -226,7 +226,7 @@ func Test_ErrorWhenCannotStartPostgresProcess(t *testing.T) {
 		return jarFile, true
 	}
 
-	database.initDatabase = func(binaryExtractLocation, runtimePath, dataLocation, username, password, locale string, logger *os.File) error {
+	database.initDatabase = func(binaryExtractLocation, runtimePath, dataLocation, username, password, locale string, encoding string, logger *os.File) error {
 		_, _ = logger.Write([]byte("ah it did not work"))
 		return nil
 	}
@@ -257,6 +257,7 @@ func Test_CustomConfig(t *testing.T) {
 		Port(9876).
 		StartTimeout(10 * time.Second).
 		Locale("C").
+		Encoding("UTF8").
 		Logger(nil))
 
 	if err := database.Start(); err != nil {
@@ -356,6 +357,36 @@ func Test_CustomLocaleConfig(t *testing.T) {
 	}
 }
 
+func Test_CustomEncodingConfig(t *testing.T) {
+	database := NewDatabase(DefaultConfig().Encoding("UTF8"))
+	if err := database.Start(); err != nil {
+		shutdownDBAndFail(t, err, database)
+	}
+
+	db, err := sql.Open("postgres", "host=localhost port=5432 user=postgres password=postgres dbname=postgres sslmode=disable")
+	if err != nil {
+		shutdownDBAndFail(t, err, database)
+	}
+
+	rows := db.QueryRow("SHOW SERVER_ENCODING;")
+
+	var (
+		value string
+	)
+	if err := rows.Scan(&value); err != nil {
+		shutdownDBAndFail(t, err, database)
+	}
+	assert.Equal(t, "UTF8", value)
+
+	if err := db.Close(); err != nil {
+		shutdownDBAndFail(t, err, database)
+	}
+
+	if err := database.Stop(); err != nil {
+		shutdownDBAndFail(t, err, database)
+	}
+}
+
 func Test_ConcurrentStart(t *testing.T) {
 	var wg sync.WaitGroup
 

prepare_database.go

@@ -18,10 +18,10 @@ const (
 	fmtAfterError  = "%v happened after error: %w"
 )
 
-type initDatabase func(binaryExtractLocation, runtimePath, pgDataDir, username, password, locale string, logger *os.File) error
+type initDatabase func(binaryExtractLocation, runtimePath, pgDataDir, username, password, locale string, encoding string, logger *os.File) error
 type createDatabase func(port uint32, username, password, database string) error
 
-func defaultInitDatabase(binaryExtractLocation, runtimePath, pgDataDir, username, password, locale string, logger *os.File) error {
+func defaultInitDatabase(binaryExtractLocation, runtimePath, pgDataDir, username, password, locale string, encoding string, logger *os.File) error {
 	passwordFile, err := createPasswordFile(runtimePath, password)
 	if err != nil {
 		return err
@@ -38,6 +38,10 @@ func defaultInitDatabase(binaryExtractLocation, runtimePath, pgDataDir, username
 		args = append(args, fmt.Sprintf("--locale=%s", locale))
 	}
 
+	if encoding != "" {
+		args = append(args, fmt.Sprintf("--encoding=%s", encoding))
+	}
+
 	postgresInitDBBinary := filepath.Join(binaryExtractLocation, "bin/initdb")
 	postgresInitDBProcess := exec.Command(postgresInitDBBinary, args...)
 	postgresInitDBProcess.Stderr = logger

prepare_database_test.go

@@ -12,7 +12,7 @@ import (
 )
 
 func Test_defaultInitDatabase_ErrorWhenCannotCreatePasswordFile(t *testing.T) {
-	err := defaultInitDatabase("path_not_exists", "path_not_exists", "path_not_exists", "Tom", "Beer", "", os.Stderr)
+	err := defaultInitDatabase("path_not_exists", "path_not_exists", "path_not_exists", "Tom", "Beer", "", "", os.Stderr)
 
 	assert.EqualError(t, err, "unable to write password file to path_not_exists/pwfile")
 }
@@ -49,7 +49,7 @@ func Test_defaultInitDatabase_ErrorWhenCannotStartInitDBProcess(t *testing.T) {
 
 	_, _ = logFile.Write([]byte("and here are the logs!"))
 
-	err = defaultInitDatabase(binTempDir, runtimeTempDir, filepath.Join(runtimeTempDir, "data"), "Tom", "Beer", "", logFile)
+	err = defaultInitDatabase(binTempDir, runtimeTempDir, filepath.Join(runtimeTempDir, "data"), "Tom", "Beer", "", "", logFile)
 
 	assert.NotNil(t, err)
 	assert.Contains(t, err.Error(), fmt.Sprintf("unable to init database using '%s/bin/initdb -A password -U Tom -D %s/data --pwfile=%s/pwfile'",
@@ -72,7 +72,7 @@ func Test_defaultInitDatabase_ErrorInvalidLocaleSetting(t *testing.T) {
 		}
 	}()
 
-	err = defaultInitDatabase(tempDir, tempDir, filepath.Join(tempDir, "data"), "postgres", "postgres", "en_XY", os.Stderr)
+	err = defaultInitDatabase(tempDir, tempDir, filepath.Join(tempDir, "data"), "postgres", "postgres", "en_XY", "", os.Stderr)
 
 	assert.NotNil(t, err)
 	assert.Contains(t, err.Error(), fmt.Sprintf("unable to init database using '%s/bin/initdb -A password -U postgres -D %s/data --pwfile=%s/pwfile --locale=en_XY'",
@@ -81,6 +81,27 @@ func Test_defaultInitDatabase_ErrorInvalidLocaleSetting(t *testing.T) {
 		tempDir))
 }
 
+func Test_defaultInitDatabase_ErrorInvalidEncodingSetting(t *testing.T) {
+	tempDir, err := os.MkdirTemp("", "prepare_database_test")
+	if err != nil {
+		panic(err)
+	}
+
+	defer func() {
+		if err := os.RemoveAll(tempDir); err != nil {
+			panic(err)
+		}
+	}()
+
+	err = defaultInitDatabase(tempDir, tempDir, filepath.Join(tempDir, "data"), "postgres", "postgres", "", "invalid", os.Stderr)
+
+	assert.NotNil(t, err)
+	assert.Contains(t, err.Error(), fmt.Sprintf("unable to init database using '%s/bin/initdb -A password -U postgres -D %s/data --pwfile=%s/pwfile --encoding=invalid'",
+		tempDir,
+		tempDir,
+		tempDir))
+}
+
 func Test_defaultInitDatabase_PwFileRemoved(t *testing.T) {
 	tempDir, err := os.MkdirTemp("", "prepare_database_test")
 	if err != nil {