camfish/phases.go

package camfish

import "os"
import "fmt"
import "log"
import "io/fs"
import "errors"
import "context"
import "strings"
import "path/filepath"
import "git.tebibyte.media/sashakoshka/go-cli"
import "git.tebibyte.media/sashakoshka/go-service/daemon"
import "git.tebibyte.media/sashakoshka/go-service/rotate"

func (this *environment) phase10FlagParsing() bool {
	// create flag set and specify built-in flags
	set := flagSet {
		name: this.name,
		description: this.description,
	}
	flagHelp          := set.Flag('h', "help",          "Display usage information and exit", nil)
	flagPidFile       := set.Flag('p', "pid-file",      "Write the PID to the specified file", cli.ValString)
	flagUser          := set.Flag('u', "user",          "The user:group to run as", cli.ValString)
	flagLogDirectory  := set.Flag('l', "log-directory", "Write logs to the specified directory", cli.ValString)
	flagConfigFile    := set.Flag('c', "config-file",   "Use this configuration file", cli.ValString)
	flagVerbose       := set.Flag('v', "verbose",       "Enable verbose output/logging", nil)

	// ask actors to add flags
	actors, done := this.actors.RBorrow()
	defer done()
	for _, actor := range sortActors(actors, actors.flagAdder.all()) {
		actor.AddFlags(&set)
	}

	// parse flags
	err := set.parse(os.Args)
	if err != nil {
		fmt.Fprintf(os.Stderr, "%s: %v\n", os.Args[0], err)
		set.usage()
		return false
	}

	// handle built-in flags
	if _, ok := flagHelp.First(); ok {
		set.usage()
		return false
	}
	if pidFile, ok := flagPidFile.First(); ok {
		this.flags.pidFile = pidFile
	}
	if user, ok := flagUser.First(); ok {
		this.flags.user = user
	}
	if logDirectory, ok := flagLogDirectory.First(); ok {
		this.flags.logDirectory = logDirectory
	}
	if configFile, ok := flagConfigFile.First(); ok {
		this.flags.configFile = configFile
	}
	if _, ok := flagVerbose.First(); ok {
		this.flags.verbose = true
	}
	return true
}

func (this *environment) phase13PidFileCreation() bool {
	if this.flags.pidFile != "" {
		err := daemon.PidFile(this.flags.pidFile).Start()
		if err != nil {
			fmt.Fprintf(os.Stderr, "%s: %v\n", os.Args[0], err)
			return false
		}
	}
	return true
}

func (this *environment) phase17PrivilegeDropping() bool {
	if this.flags.user != "" {
		if this.Verb() {
			fmt.Fprintf(os.Stderr,
				"%s: dropping privilege to %s\n",
				os.Args[0], this.flags.user)
		}
		user, group, _ := strings.Cut(this.flags.user, ":")
		err := dropPrivelege(user, group)
		fmt.Fprintf(os.Stderr, "%s: could not drop privilege %v\n", os.Args[0], err)
	}
	return true
}

func (this *environment) phase20LogSwitching() bool {
	if this.flags.logDirectory != "" {
		directory := this.flags.logDirectory
		if this.Verb() {
			fmt.Fprintf(os.Stderr,
				"%s: logging to %s\n",
				os.Args[0], directory)
		}
		directory, err := filepath.Abs(directory)
		if err != nil {
			fmt.Fprintf(os.Stderr, "%s: could not rotate logs: %v\n", os.Args[0], err)
			return false
		}
		logger, err := rotate.New(directory)
		if err != nil {
			fmt.Fprintf(os.Stderr, "%s: could not rotate logs: %v\n", os.Args[0], err)
			return false
		}
		defer logger.Close()
		log.SetOutput(logger)
	}
	log.Printf("====== [%s] START =======", this.name)
	log.Printf("(i) (20) CAMFISH environment %s", version)
	logActors(All())
	return true
}

func (this *environment) phase30ConfigurationParsing() bool {
	if this.Verb() { log.Println("... (30) parsing configuration") }
	// blank config if nothing happens
	this.conf = make(iniConfig)
	// get list of config files
	paths, err := configFiles(this.name)
	if err != nil {
		log.Println("!!! (30) could not determine location of file(s):", err)
		return true
	}
	if this.flags.configFile != "" {
		paths = append(paths, this.flags.configFile)
	}
	// parse every config and merge them all
	configs := make([]iniConfig, 0, len(paths))
	for _, path := range paths {
		file, err := os.Open(path)
		if err != nil {
			if !errors.Is(err, fs.ErrNotExist) {
				log.Println("!!! (30) file present but inaccessible:", err)
			} else if path == this.flags.configFile {
				log.Println("!!! (30)", err)
			}
			continue
		}
		defer file.Close()
		config, err := DecodeINI(path, file)
		if err != nil {
			log.Println("!!! (30) could not parse:", err)
			continue
		}
		configs = append(configs, config.(iniConfig))
	}
	this.conf = mergeINI(configs...)
	if this.Verb() { log.Println(".// (30) parsed configuration") }
	return true
}

func (this *environment) phase40ConfigurationProcessing() bool {
	if this.Verb() { log.Println("... (40) processing configuration") }
	actors, done := this.actors.RBorrow()
	defer done()
	for _, actor := range sortActors(actors, actors.configProcessor.all()) {
		err := actor.ProcessConfig(this.conf)
		if err != nil {
			log.Println("XXX (50) could not process configuration:", err)
			return false
		}
	}
	if this.Verb() { log.Println(".// (40) processed configuration") }
	return true
}

func (this *environment) phase50ConfigurationApplication() bool {
	if this.Verb() { log.Println("... (50) applying configuration") }
	err := this.applyConfig()
	if err != nil {
		log.Println("XXX (50) could not apply configuration:", err)
		return false
	}
	actors, done := this.actors.RBorrow()
	defer done()
	for _, actor := range sortActors(actors, actors.configurable.all()) {
		err := actor.Configure(this.conf)
		if err != nil {
			log.Printf (
				"XXX (50) could not apply configuration to %s: %v",
				actor.(Actor).Type(), err)
			return false
		}
	}
	if this.Verb() { log.Println(".// (50) applied configuration") }
	return true
}

func (this *environment) phase60Initialization() bool {
	if this.Verb() { log.Println("... (60) initializing") }
	var initializable []Initializable
	func() {
		actors, done := this.actors.RBorrow()
		defer done()
		initializable = actors.initializable.all()
	}()
	if err := this.initializeActors(this.ctx, initializable...); err != nil {
		log.Println(".// (60) failed to initialize:", err)
		return false
	}
	if this.Verb() { log.Println(".// (60) initialized") }
	return true
}

func (this *environment) phase70Running() bool {
	defer this.Done(nil)
	if this.Verb() { log.Println("... (70) starting up") }
	this.running.Store(true)
	defer this.running.Store(false)
	func() {
		actors, done := this.actors.RBorrow()
		defer done()
		for _, actor := range actors.runnable.all() {
			this.start(actor)
		}
		
	}()
	log.Println(".// (70) startup sequence complete")
	// await context cancellation or waitgroup completion
	wgChannel := make(chan struct { }, 1)
	go func() {
		this.group.Wait()
		wgChannel <- struct { } { }
	}()
	select {
	case <- this.ctx.Done():
		if this.Verb() { log.Println("(i) (70) canceled") }
	case <- wgChannel:
		if this.Verb() { log.Println("(i) (70) all actors have finished") }
	}
	return true
}

func (this *environment) phase70_5Trimming() bool {
	if this.Verb() { log.Println("... (70.5) trimming") }
	var trimmable []Trimmable
	func() {
		actors, done := this.actors.RBorrow()
		defer done()
		trimmable = actors.trimmable.all()
	}()
	if err := this.trimActors(this.ctx, trimmable...); err != nil {
		log.Println(".// (70.5) failed to trim:", err)
		return false
	}
	if this.Verb() { log.Println(".// (70.5) trimmed") }
	return true
}

func (this *environment) phase80Shutdown() bool {
	cause := context.Cause(this.ctx)
	if cause != nil {
		log.Println("XXX (80) shutting down because:", cause)
	}
	log.Println("... (80) waiting for actors to shut down")
	defer func() {
		log.Println(".// (80) shutdown succeeded, goodbye")
		log.Printf("====== [%s] END =======", this.name)
	}()
	this.group.Wait()
	return cause == nil
}