Pull request 2156: 6717-conf-path-logs

Updates #6717.

Squashed commit of the following:

commit 05a7e18923e987ea9bd6294fe675a22cf86f6dce
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Wed Feb 21 16:44:00 2024 +0300

    home: imp docs, logs

internal/home/config.go

@@ -456,20 +456,25 @@ var config = &configuration{
 	Theme:         ThemeAuto,
 }
 
-// getConfigFilename returns path to the current config file
-func (c *configuration) getConfigFilename() string {
-	configFile, err := filepath.EvalSymlinks(Context.configFilename)
+// configFilePath returns the absolute path to the symlink-evaluated path to the
+// current config file.
+func configFilePath() (confPath string) {
+	confPath, err := filepath.EvalSymlinks(Context.confFilePath)
 	if err != nil {
-		if !errors.Is(err, os.ErrNotExist) {
-			log.Error("unexpected error while config file path evaluation: %s", err)
-		}
-		configFile = Context.configFilename
-	}
-	if !filepath.IsAbs(configFile) {
-		configFile = filepath.Join(Context.workDir, configFile)
+		confPath = Context.confFilePath
+		logFunc := log.Error
+		if errors.Is(err, os.ErrNotExist) {
+			logFunc = log.Debug
 		}
 
-	return configFile
+		logFunc("evaluating config path: %s; using %q", err, confPath)
+	}
+
+	if !filepath.IsAbs(confPath) {
+		confPath = filepath.Join(Context.workDir, confPath)
+	}
+
+	return confPath
 }
 
 // validateBindHosts returns error if any of binding hosts from configuration is
@@ -510,7 +515,10 @@ func parseConfig() (err error) {
 		// Don't wrap the error, because it's informative enough as is.
 		return err
 	} else if upgraded {
-		err = maybe.WriteFile(config.getConfigFilename(), config.fileData, 0o644)
+		confPath := configFilePath()
+		log.Debug("writing config file %q after config upgrade", confPath)
+
+		err = maybe.WriteFile(confPath, config.fileData, 0o644)
 		if err != nil {
 			return fmt.Errorf("writing new config: %w", err)
 		}
@@ -531,12 +539,8 @@ func parseConfig() (err error) {
 		config.DNS.UpstreamTimeout = timeutil.Duration{Duration: dnsforward.DefaultTimeout}
 	}
 
-	err = setContextTLSCipherIDs()
-	if err != nil {
-		return err
-	}
-
-	return nil
+	// Do not wrap the error because it's informative enough as is.
+	return setContextTLSCipherIDs()
 }
 
 // validateConfig returns error if the configuration is invalid.
@@ -600,11 +604,11 @@ func readConfigFile() (fileData []byte, err error) {
 		return config.fileData, nil
 	}
 
-	name := config.getConfigFilename()
-	log.Debug("reading config file: %s", name)
+	confPath := configFilePath()
+	log.Debug("reading config file %q", confPath)
 
 	// Do not wrap the error because it's informative enough as is.
-	return os.ReadFile(name)
+	return os.ReadFile(confPath)
 }
 
 // Saves configuration to the YAML file and also saves the user filter contents to a file
@@ -668,8 +672,8 @@ func (c *configuration) write() (err error) {
 
 	config.Clients.Persistent = Context.clients.forConfig()
 
-	configFile := config.getConfigFilename()
-	log.Debug("writing config file %q", configFile)
+	confPath := configFilePath()
+	log.Debug("writing config file %q", confPath)
 
 	buf := &bytes.Buffer{}
 	enc := yaml.NewEncoder(buf)
@@ -680,7 +684,7 @@ func (c *configuration) write() (err error) {
 		return fmt.Errorf("generating config file: %w", err)
 	}
 
-	err = maybe.WriteFile(configFile, buf.Bytes(), 0o644)
+	err = maybe.WriteFile(confPath, buf.Bytes(), 0o644)
 	if err != nil {
 		return fmt.Errorf("writing config file: %w", err)
 	}

internal/home/home.go

@@ -40,7 +40,6 @@ import (
 	"github.com/AdguardTeam/golibs/log"
 	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/AdguardTeam/golibs/osutil"
-	"github.com/AdguardTeam/golibs/stringutil"
 )
 
 // Global context
@@ -68,7 +67,10 @@ type homeContext struct {
 	// Runtime properties
 	// --
 
-	configFilename string // Config filename (can be overridden via the command line arguments)
+	// confFilePath is the configuration file path as set by default or from the
+	// command-line options.
+	confFilePath string
+
 	workDir     string // Location of our directory, used to protect against CWD being somewhere else
 	pidFileName string // PID file name.  Empty if no PID file was created.
 	controlLock sync.Mutex
@@ -575,6 +577,9 @@ func run(opts options, clientBuildFS fs.FS, done chan struct{}) {
 		Path: path.Join("adguardhome", version.Channel(), "version.json"),
 	}
 
+	confPath := configFilePath()
+	log.Debug("using config path %q for updater", confPath)
+
 	upd := updater.NewUpdater(&updater.Config{
 		Client:          config.Filtering.HTTPClient,
 		Version:         version.Version(),
@@ -584,7 +589,7 @@ func run(opts options, clientBuildFS fs.FS, done chan struct{}) {
 		GOARM:           version.GOARM(),
 		GOMIPS:          version.GOMIPS(),
 		WorkDir:         Context.workDir,
-		ConfName:        config.getConfigFilename(),
+		ConfName:        confPath,
 		ExecPath:        execPath,
 		VersionCheckURL: u.String(),
 	})
@@ -748,7 +753,16 @@ func writePIDFile(fn string) bool {
 // initConfigFilename sets up context config file path.  This file path can be
 // overridden by command-line arguments, or is set to default.
 func initConfigFilename(opts options) {
-	Context.configFilename = stringutil.Coalesce(opts.confFilename, "AdGuardHome.yaml")
+	confPath := opts.confFilename
+	if confPath == "" {
+		Context.confFilePath = "AdGuardHome.yaml"
+
+		return
+	}
+
+	log.Debug("config path overridden to %q from cmdline", confPath)
+
+	Context.confFilePath = confPath
 }
 
 // initWorkingDir initializes the workDir.  If no command-line arguments are
@@ -906,16 +920,23 @@ func printHTTPAddresses(proto string) {
 	}
 }
 
-// -------------------
-// first run / install
-// -------------------
-func detectFirstRun() bool {
-	configfile := Context.configFilename
-	if !filepath.IsAbs(configfile) {
-		configfile = filepath.Join(Context.workDir, Context.configFilename)
+// detectFirstRun returns true if this is the first run of AdGuard Home.
+func detectFirstRun() (ok bool) {
+	confPath := Context.confFilePath
+	if !filepath.IsAbs(confPath) {
+		confPath = filepath.Join(Context.workDir, Context.confFilePath)
 	}
-	_, err := os.Stat(configfile)
-	return errors.Is(err, os.ErrNotExist)
+
+	_, err := os.Stat(confPath)
+	if err == nil {
+		return false
+	} else if errors.Is(err, os.ErrNotExist) {
+		return true
+	}
+
+	log.Error("detecting first run: %s; considering first run", err)
+
+	return true
 }
 
 // jsonError is a generic JSON error response.

internal/home/log.go

@@ -75,6 +75,8 @@ func getLogSettings(opts options) (ls *logSettings) {
 	if opts.verbose {
 		ls.Verbose = true
 	}
+
+	// TODO(a.garipov): Use cmp.Or in Go 1.22.
 	ls.File = stringutil.Coalesce(opts.logFile, ls.File)
 
 	if opts.runningAsService && ls.File == "" && runtime.GOOS == "windows" {

internal/home/service.go

@@ -227,12 +227,15 @@ func handleServiceControlAction(
 	runOpts := opts
 	runOpts.serviceControlAction = "run"
 
+	args := optsToArgs(runOpts)
+	log.Debug("service: using args %q", args)
+
 	svcConfig := &service.Config{
 		Name:             serviceName,
 		DisplayName:      serviceDisplayName,
 		Description:      serviceDescription,
 		WorkingDirectory: pwd,
-		Arguments:        optsToArgs(runOpts),
+		Arguments:        args,
 	}
 	configureService(svcConfig)