feat(cmd/influxd): use a better default for upgraded V2 config, and a…

…llow users to override it (#20110)

CHANGELOG.md

@@ -1,12 +1,27 @@
 ## unreleased
 
+### Breaking Changes
+
+Previously, `influxd upgrade` would attempt to write upgraded `config.toml` files into the same directory as the source
+`influxdb.conf` file. If this failed, a warning would be logged and `config.toml` would be written into the `HOME` directory.
+
+This release breaks this behavior in two ways:
+1. By default, `config.toml` is now written into the same directory as the Bolt DB and engine files (`~/.influxdbv2/`)
+2. If writing upgraded config fails, the `upgrade` process exits with an error instead of falling back to the `HOME` directory
+
+Users can use the new `--v2-config-path` option to override the output path for upgraded config if they can't or don't
+want to use the default.
+
 ### Features
 
 1. [20123](https://github.com/influxdata/influxdb/pull/20123): Allow password to be specified as a CLI option in `influx v1 auth create`.
 1. [20123](https://github.com/influxdata/influxdb/pull/20123): Allow password to be specified as a CLI option in `influx v1 auth set-password`.
+1. [20110](https://github.com/influxdata/influxdb/pull/20110): Allow for users to specify where V2 config should be written in `influxd upgrade`.
 
 ### Bug Fixes
 
+1. [20110](https://github.com/influxdata/influxdb/pull/20110): Use V2 directory for default V2 config path in `influxd upgrade`.
+
 ## v2.0.2 [2020-11-19]
 
 ### Features

cmd/influxd/upgrade/config.go

@@ -4,7 +4,6 @@ package upgrade
 // The strategy is to transform only those entries for which rule exists.
 
 import (
-	"bytes"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -109,25 +108,22 @@ func load(path string) ([]byte, error) {
 }
 
 // upgradeConfig upgrades existing 1.x configuration file to 2.x influxdb.toml file.
-func upgradeConfig(v1Config map[string]interface{}, targetOptions optionsV2, log *zap.Logger) (string, error) {
+func upgradeConfig(v1Config map[string]interface{}, targetOptions optionsV2, log *zap.Logger) error {
 	// create and initialize helper
 	cu := &configUpgrader{
 		rules:           configMapRules,
 		valueTransforms: configValueTransforms,
 		log:             log,
 	}
 
+	// rewrite config options from V1 to V2 paths
 	cTransformed := cu.transform(v1Config)
 
 	// update new config with upgrade command options
 	cu.updateV2Config(cTransformed, targetOptions)
 
-	configFileV2, err := cu.save(cTransformed, targetOptions.configPath)
-	if err != nil {
-		return "", err
-	}
-
-	return configFileV2, nil
+	// write the ugpraded config to disk
+	return cu.save(cTransformed, targetOptions.configPath)
 }
 
 // configUpgrader is a helper used by `upgrade-config` command.
@@ -146,20 +142,19 @@ func (cu *configUpgrader) updateV2Config(config map[string]interface{}, targetOp
 	}
 }
 
-func (cu *configUpgrader) save(config map[string]interface{}, path string) (string, error) {
-	buf := new(bytes.Buffer)
-	if err := toml.NewEncoder(buf).Encode(&config); err != nil {
-		return "", err
+func (cu *configUpgrader) save(config map[string]interface{}, path string) error {
+	// Open the target file, creating parent directories if needed.
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+		return err
 	}
-
-	err := ioutil.WriteFile(path, buf.Bytes(), 0666)
-	if err != nil { // permission issue possible - try to save the file to home or current dir
-		cu.log.Warn(fmt.Sprintf("Could not save upgraded config to %s, trying to save it to user's home.", path), zap.Error(err))
-		path = filepath.Join(homeOrAnyDir(), filepath.Base(path))
-		err = ioutil.WriteFile(path, buf.Bytes(), 0666)
+	outFile, err := os.OpenFile(path, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0644)
+	if err != nil {
+		return err
 	}
+	defer outFile.Close()
 
-	return path, err
+	// Encode the config directly into the file as TOML.
+	return toml.NewEncoder(outFile).Encode(&config)
 }
 
 // Credits: @rogpeppe (Roger Peppe)

cmd/influxd/upgrade/config_test.go

@@ -62,11 +62,8 @@ func TestConfigUpgrade(t *testing.T) {
 			if _, err = toml.Decode(tc.config1x, &rawV1Config); err != nil {
 				t.Fatal(err)
 			}
-			retval, err := upgradeConfig(rawV1Config, targetOtions, zaptest.NewLogger(t))
-			if err != nil {
-				t.Fatal(err)
-			}
-			assert.Equal(t, retval, configFileV2)
+			err = upgradeConfig(rawV1Config, targetOtions, zaptest.NewLogger(t))
+			assert.NoError(t, err)
 
 			var actual, expected map[string]interface{}
 			if _, err = toml.Decode(tc.config2x, &expected); err != nil {

cmd/influxd/upgrade/upgrade.go

@@ -238,6 +238,12 @@ func NewCommand(v *viper.Viper) *cobra.Command {
 			Flag:  "config-file",
 			Desc:  "optional: Custom InfluxDB 1.x config file path, else the default config file",
 		},
+		{
+			DestP:   &options.target.configPath,
+			Flag:    "v2-config-path",
+			Default: filepath.Join(v2dir, "config.toml"),
+			Desc:    "optional: Custom path where upgraded 2.x config should be written",
+		},
 		{
 			DestP:   &options.logLevel,
 			Flag:    "log-level",
@@ -355,8 +361,6 @@ func runUpgradeE(*cobra.Command, []string) error {
 		options.source.dataDir = v1Config.Data.Dir
 		options.source.walDir = v1Config.Data.WALDir
 		options.source.dbURL = v1Config.dbURL()
-
-		options.target.configPath = filepath.Join(filepath.Dir(options.source.configFile), "config.toml")
 	} else {
 		// Otherwise, assume a standard directory layout.
 		options.source.populateDirs()
@@ -371,15 +375,15 @@ func runUpgradeE(*cobra.Command, []string) error {
 
 	if genericV1ops != nil {
 		log.Info("Upgrading config file", zap.String("file", options.source.configFile))
-		v2ConfigPath, err := upgradeConfig(*genericV1ops, options.target, log)
-		if err != nil {
+		if err := upgradeConfig(*genericV1ops, options.target, log); err != nil {
 			return err
 		}
 		log.Info(
 			"Config file upgraded.",
 			zap.String("1.x config", options.source.configFile),
-			zap.String("2.x config", v2ConfigPath),
+			zap.String("2.x config", options.target.configPath),
 		)
+
 	} else {
 		log.Info("No InfluxDB 1.x config file specified, skipping its upgrade")
 	}