split into packages

merlin/arthur/arthur.go

@@ -0,0 +1,114 @@
+package arthur
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"text/tabwriter"
+	"time"
+
+	"git.csclub.uwaterloo.ca/public/merlin/config"
+	"git.csclub.uwaterloo.ca/public/merlin/logger"
+	"git.csclub.uwaterloo.ca/public/merlin/sync"
+)
+
+// get repo by name function in config
+
+func GetAndRunCommand(conn net.Conn) (newSync bool) {
+	newSync = false
+	defer conn.Close()
+
+	var buf bytes.Buffer
+	_, err := io.Copy(&buf, conn)
+	if err != nil {
+		logger.ErrLog(err.Error())
+		return
+	}
+
+	command := buf.String()
+	args := strings.Split(command, ":")
+	respondAndLogErr := func(msg string) {
+		logger.OutLog(msg)
+		conn.Write([]byte(msg))
+	}
+
+	if args[0] == "status" {
+		status := tabwriter.NewWriter(conn, 5, 5, 5, ' ', 0)
+		fmt.Fprintf(status, "Repository\tLast Synced\tNext Expected Sync\n")
+
+		// for time formating see https://pkg.go.dev/time#pkg-constants
+		for name, repo := range config.RepoMap {
+			fmt.Fprintf(status, "%s\t%s\t%s\n",
+				name,
+				time.Unix(repo.State.LastAttemptStartTime, 0).Format(time.RFC1123),
+				time.Unix(repo.State.LastAttemptRunTime+int64(repo.Frequency), 0).Format(time.RFC1123),
+			)
+		}
+
+		status.Flush()
+	} else if args[0] == "sync" {
+		if len(args) != 2 {
+			respondAndLogErr("Could not parse sync command, forced sync fails.")
+			return
+		}
+
+		if repo, inMap := config.RepoMap[args[1]]; inMap {
+			logger.OutLog("Attempting to force sync of " + repo.Name)
+			if sync.SyncIfPossible(repo) {
+				conn.Write([]byte("Forced sync for " + repo.Name))
+				newSync = true
+			} else {
+				respondAndLogErr("Cannot force sync: " + repo.Name + ", already syncing.")
+			}
+		} else {
+			respondAndLogErr(args[1] + " is not tracked so cannot sync")
+		}
+	} else {
+		respondAndLogErr("Received unrecognized command: " + command)
+	}
+	return
+}
+
+func UnixSockListener(connChan chan net.Conn, stopLisChan chan struct{}) {
+	sockpath := config.Conf.SockPath
+	// must remove cfg.SockPath otherwise get "bind: address already in use"
+	if filepath.Ext(sockpath) != ".sock" {
+		panic(fmt.Errorf("Socket file must end with .sock"))
+	} else if _, err := os.Stat(sockpath); err == nil {
+		if err := os.Remove(sockpath); err != nil {
+			panic(err)
+		}
+	} else if !errors.Is(err, os.ErrNotExist) {
+		panic(err)
+	}
+
+	ear, err := net.Listen("unix", sockpath)
+	if err != nil {
+		panic(err)
+	}
+	logger.OutLog("Listening to unix socket at " + sockpath)
+
+	go func() {
+		for {
+			// will exit when ear is closed
+			conn, err := ear.Accept()
+			if err != nil {
+				if ne, ok := err.(net.Error); ok && ne.Temporary() {
+					logger.ErrLog("Accepted socket error: " + err.Error())
+					continue
+				}
+				logger.ErrLog("Unhandlable socket error: " + err.Error())
+				return
+			}
+			connChan <- conn
+		}
+	}()
+
+	<-stopLisChan
+	ear.Close()
+}

merlin/arthur/arthur_test.go

@@ -0,0 +1 @@
+package arthur

merlin/common/tests/common_test.go

@@ -1 +0,0 @@
-package common

merlin/config/config.go

@@ -1,12 +1,11 @@
-package common
+package config
 
 import (
-	"fmt"
 	"os"
-	"os/exec"
-	"time"
 
-	ini "gopkg.in/ini.v1"
+	"gopkg.in/ini.v1"
+
+	"git.csclub.uwaterloo.ca/public/merlin/logger"
 )
 
 const (
@@ -51,11 +50,39 @@ const (
 	TERMINATED // was killed by a signal
 )
 
-type Result struct {
+type SyncResult struct {
 	Name string
 	Exit int
 }
 
+type Config struct {
+	// the maximum number of jobs allowed to execute concurrently
+	MaxJobs int `ini:"max_jobs"`
+	// the IP addresses to use for rsync
+	IPv4Address string `ini:"ipv4_address"`
+	IPv6Address string `ini:"ipv6_address"`
+	// the default sync type
+	SyncType string `ini:"default_sync_type"`
+	// the default frequency string for the repos
+	FrequencyStr string `ini:"default_frequency"`
+	// the default MaxTime for each repo
+	MaxTime int `ini:"default_max_time"`
+	// the directory where rsync should download files
+	DownloadDir string `ini:"download_dir"`
+	// the directory where rsync passwords are stored
+	PasswordDir string `ini:"password_dir"`
+	// the directory where the state of each repo sync is saved
+	StateDir string `ini:"states_dir"`
+	// the directory where merlin will store the general logs for each repo
+	LoggerDir string `ini:"log_dir"`
+	// the directory to store the rsync logs for each repo
+	RsyncLogDir string `ini:"rsync_log_dir"`
+	// the directory to store the zfssync logs for each repo
+	ZfssyncLogDir string `ini:"zfssync_log_dir"`
+	// the Unix socket path which arthur will use to communicate with us
+	SockPath string `ini:"sock_path"`
+}
+
 type Repo struct {
 	// the name of this repo
 	Name string `ini:"-"`
@@ -82,50 +109,18 @@ type Repo struct {
 	// the file for general logging of this repo
 	LoggerFile string `ini:"log_file"`
 	// a reference to the general logger
-	Logger *Logger `ini:"-"`
+	Logger *logger.Logger `ini:"-"`
 	// the file for logging this repo's rsync
 	RsyncLogFile string `ini:"rsync_log_file"`
 	// the file for logging this repo's zfssync
 	ZfssyncLogFile string `ini:"zfssync_log_file"`
 	// the repo will write its name and status in a Result struct to DoneChan
 	// when it has finished a job (shared by all repos)
-	DoneChan chan<- Result `ini:"-"`
+	DoneChan chan<- SyncResult `ini:"-"`
 	// the repo should stop syncing if StopChan is closed (shared by all repos)
 	StopChan chan struct{} `ini:"-"`
 	// a struct that stores the repo's status
 	State RepoState `ini:"-"`
-	// a reference to the global config
-	cfg *Config `ini:"-"`
-}
-
-type Config struct {
-	// the maximum number of jobs allowed to execute concurrently
-	MaxJobs int `ini:"max_jobs"`
-	// the IP addresses to use for rsync
-	IPv4Address string `ini:"ipv4_address"`
-	IPv6Address string `ini:"ipv6_address"`
-	// the default sync type
-	SyncType string `ini:"default_sync_type"`
-	// the default frequency string for the repos
-	FrequencyStr string `ini:"default_frequency"`
-	// the default MaxTime for each repo
-	MaxTime int `ini:"default_max_time"`
-	// the directory where rsync should download files
-	DownloadDir string `ini:"download_dir"`
-	// the directory where rsync passwords are stored
-	PasswordDir string `ini:"password_dir"`
-	// the directory where the state of each repo sync is saved
-	StateDir string `ini:"states_dir"`
-	// the directory where merlin will store the general logs for each repo
-	LoggerDir string `ini:"log_dir"`
-	// the directory to store the rsync logs for each repo
-	RsyncLogDir string `ini:"rsync_log_dir"`
-	// the directory to store the zfssync logs for each repo
-	ZfssyncLogDir string `ini:"zfssync_log_dir"`
-	// the Unix socket path which arthur will use to communicate with us
-	SockPath string `ini:"sock_path"`
-	// a list of all of the repos
-	Repos []*Repo `ini:"-"`
 }
 
 // This should only be modified by the main thread
@@ -141,129 +136,18 @@ type RepoState struct {
 	LastAttemptExit int `ini:"last_attempt_exit"`
 }
 
-// save the current state of the repo to a file
-func (repo *Repo) SaveState() {
-	repo.Logger.Debug("Saving state")
-	state_cfg := ini.Empty()
-	if err := ini.ReflectFrom(state_cfg, &repo.State); err != nil {
-		repo.Logger.Error(err.Error())
-	}
-	file, err := os.OpenFile(repo.cfg.StateDir+"/"+repo.Name, os.O_RDWR|os.O_CREATE, 0644)
-	if err != nil {
-		repo.Logger.Error(err.Error())
-	}
-	if _, err := state_cfg.WriteTo(file); err != nil {
-		repo.Logger.Error(err.Error())
-	}
-	repo.Logger.Debug("Saved state")
-}
-
-// start sync job for this repo if more than repo.Frequency seconds have elapsed since its last job
-// and is not currently running.
-// returns true iff a job is started.
-func (repo *Repo) RunIfPossible() bool {
-	if repo.State.IsRunning {
-		return false
-	}
-
-	curTime := time.Now().Unix()
-	if curTime-repo.State.LastAttemptStartTime > int64(repo.Frequency) {
-		repo.State.IsRunning = true
-		repo.State.LastAttemptStartTime = curTime
-		repo.SaveState()
-		repo.Logger.Info(fmt.Sprintf("Repo %s has started syncing", repo.Name))
-		go repo.StartSyncJob()
-		return true
-	}
-	return false
-}
-
-func zfsSync(repo *Repo) {
-	out, err := exec.Command("/home/mirror/bin/zfssync", repo.Name).CombinedOutput()
-	if err != nil {
-		repo.Logger.Error(err)
-	} else {
-		f, err := os.OpenFile(repo.ZfssyncLogFile, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
-		if err != nil {
-			repo.Logger.Error(err.Error())
-		} else {
-			f.Write(out)
-		}
-
-	}
-}
-
-// update the repo state with the last attempt time and exit now that the job is done
-func (repo *Repo) SyncCompleted(exit int) {
-	repoState := repo.State
-	syncTook := time.Now().Unix() - repoState.LastAttemptStartTime
-	nextSync := repo.MaxTime - int(syncTook)
-	if nextSync < 0 {
-		nextSync = 0
-	}
-
-	repoState.IsRunning = false
-	repoState.LastAttemptExit = exit
-	repoState.LastAttemptRunTime = syncTook
-
-	var exitStr string
-	switch exit {
-	case SUCCESS:
-		exitStr = "completed"
-	case TERMINATED:
-		exitStr = "terminated"
-	default:
-		exitStr = "failed"
-	}
-	repo.SaveState()
-	repo.Logger.Info(fmt.Sprintf("Sync "+exitStr+" after running for %d seconds, will run again in %d seconds", syncTook, nextSync))
-	if exit == SUCCESS {
-		// it is possible that the zfssync from the last repo sync is still running is that fine?
-		go zfsSync(repo)
-	}
-}
-
-func panicIfErr(e error) {
-	if e != nil {
-		panic(e)
-	}
-}
-
-func touchFile(file string) {
-	fi, err := os.Stat(file)
-	if err != nil {
-		f, err := os.OpenFile(file, os.O_CREATE, 0644)
-		if err != nil {
-			panic(fmt.Errorf("unable to create file %s", file))
-		}
-		f.Close()
-	} else if fi.IsDir() {
-		panic(fmt.Errorf("%s is a directory", file))
-	} else if os.Geteuid() != 1001 {
-		// UID 1001 is the hardcoded uid for mirror
-		err := os.Chown(file, 1001, os.Getegid())
-		panicIfErr(err)
-	} else if fi.Mode().Perm() != 0644 {
-		err := os.Chmod(file, 0644)
-		panicIfErr(err)
-	}
-}
-
-func touchFiles(files ...string) {
-	for _, file := range files {
-		touchFile(file)
-	}
-}
+var (
+	Conf    Config
+	Repos   []*Repo
+	RepoMap map[string]*Repo
+)
 
 // GetConfig reads the config from a JSON file, initializes default values,
 // and initializes the non-configurable fields of each repo.
 // It returns a Config.
-func GetConfig(doneChan chan Result, stopChan chan struct{}) Config {
-	// add global configuration in cfg
-	data, err := ini.Load(CONFIG_PATH)
-	panicIfErr(err)
-
-	cfg := Config{
+func LoadConfig(doneChan chan SyncResult, stopChan chan struct{}) {
+	// set default values then load config from file
+	newConf := Config{
 		MaxJobs:       DEFAULT_MAX_JOBS,
 		MaxTime:       DEFAULT_MAX_TIME,
 		PasswordDir:   DEFAULT_PASSWORD_DIR,
@@ -273,36 +157,39 @@ func GetConfig(doneChan chan Result, stopChan chan struct{}) Config {
 		RsyncLogDir:   DEFAULT_RSYNC_LOG_DIR,
 		ZfssyncLogDir: DEFAULT_ZFSSYNC_LOG_DIR,
 		SockPath:      DEFAULT_SOCK_PATH,
-		Repos:         make([]*Repo, 0),
 	}
-	err = data.MapTo(&cfg)
+	iniInfo, err := ini.Load(CONFIG_PATH)
+	panicIfErr(err)
+	err = iniInfo.MapTo(&newConf)
 	panicIfErr(err)
 
-	for _, dir := range []string{cfg.StateDir, cfg.LoggerDir, cfg.RsyncLogDir, cfg.ZfssyncLogDir} {
+	// check config for major errors
+	for _, dir := range []string{Conf.StateDir, Conf.LoggerDir, Conf.RsyncLogDir, Conf.ZfssyncLogDir} {
 		err := os.MkdirAll(dir, 0755)
 		panicIfErr(err)
 	}
-	if cfg.IPv4Address == "" {
+	if Conf.IPv4Address == "" {
 		panic("Missing IPv4 address from config")
-	} else if cfg.IPv6Address == "" {
+	} else if Conf.IPv6Address == "" {
 		panic("Missing IPv6 address from config")
 	}
 
-	// add each repo configuration to cfg
-	for _, section := range data.Sections() {
+	newRepos := make([]*Repo, 0)
+	for _, section := range iniInfo.Sections() {
 		repoName := section.Name()
 		if repoName == "DEFAULT" {
 			continue
 		}
 
+		// set the default values for the repo then load from file
 		repo := Repo{
 			Name:           repoName,
-			SyncType:       cfg.SyncType,
-			FrequencyStr:   cfg.FrequencyStr,
-			MaxTime:        cfg.MaxTime,
-			LoggerFile:     cfg.LoggerDir + "/" + repoName + ".log",
-			RsyncLogFile:   cfg.RsyncLogDir + "/" + repoName + "-rsync.log",
-			ZfssyncLogFile: cfg.ZfssyncLogDir + "/" + repoName + "-zfssync.log",
+			SyncType:       Conf.SyncType,
+			FrequencyStr:   Conf.FrequencyStr,
+			MaxTime:        Conf.MaxTime,
+			LoggerFile:     Conf.LoggerDir + "/" + repoName + ".log",
+			RsyncLogFile:   Conf.RsyncLogDir + "/" + repoName + "-rsync.log",
+			ZfssyncLogFile: Conf.ZfssyncLogDir + "/" + repoName + "-zfssync.log",
 			DoneChan:       doneChan,
 			StopChan:       stopChan,
 		}
@@ -314,15 +201,13 @@ func GetConfig(doneChan chan Result, stopChan chan struct{}) Config {
 			repo.RsyncLogFile,
 			repo.ZfssyncLogFile,
 		)
-
-		repo.Logger = NewLogger(repo.Name, repo.LoggerFile)
+		repo.Logger = logger.NewLogger(repo.Name, repo.LoggerFile)
 		repo.Frequency = frequencies[repo.FrequencyStr]
 		if repo.SyncType == "" {
 			panic("Missing sync type from " + repo.Name)
 		} else if repo.Frequency == 0 {
 			panic("Missing or invalid frequency for " + repo.Name)
 		}
-		repo.cfg = &cfg
 
 		repo.State = RepoState{
 			IsRunning:            false,
@@ -332,7 +217,7 @@ func GetConfig(doneChan chan Result, stopChan chan struct{}) Config {
 		}
 
 		// create the state file if it does not exist, otherwise load it from existing file
-		repoStateFile := cfg.StateDir + "/" + repo.Name
+		repoStateFile := Conf.StateDir + "/" + repo.Name
 		if _, err := os.Stat(repoStateFile); err != nil {
 			touchFile(repoStateFile)
 			repo.SaveState()
@@ -341,12 +226,33 @@ func GetConfig(doneChan chan Result, stopChan chan struct{}) Config {
 			panicIfErr(err)
 		}
 
-		cfg.Repos = append(cfg.Repos, &repo)
+		newRepos = append(newRepos, &repo)
 	}
 
-	if len(cfg.Repos) == 0 {
+	if len(newRepos) == 0 {
 		panic("No repos found in config")
 	}
 
-	return cfg
+	Conf = newConf
+	Repos = newRepos
+	for _, repo := range Repos {
+		RepoMap[repo.Name] = repo
+	}
+}
+
+// save the current state of the repo to a file
+func (repo *Repo) SaveState() {
+	repo.Logger.Debug("Saving state")
+	state_cfg := ini.Empty()
+	if err := ini.ReflectFrom(state_cfg, &repo.State); err != nil {
+		repo.Logger.Error(err.Error())
+	}
+	file, err := os.OpenFile(Conf.StateDir+"/"+repo.Name, os.O_RDWR|os.O_CREATE, 0644)
+	if err != nil {
+		repo.Logger.Error(err.Error())
+	}
+	if _, err := state_cfg.WriteTo(file); err != nil {
+		repo.Logger.Error(err.Error())
+	}
+	repo.Logger.Debug("Saved state")
 }

merlin/config/config_test.go

@@ -0,0 +1 @@
+package config

merlin/config/utils.go

@@ -0,0 +1,38 @@
+package config
+
+import (
+	"fmt"
+	"os"
+)
+
+func panicIfErr(e error) {
+	if e != nil {
+		panic(e)
+	}
+}
+
+func touchFile(file string) {
+	fi, err := os.Stat(file)
+	if err != nil {
+		f, err := os.OpenFile(file, os.O_CREATE, 0644)
+		if err != nil {
+			panic(fmt.Errorf("unable to create file %s", file))
+		}
+		f.Close()
+	} else if fi.IsDir() {
+		panic(fmt.Errorf("%s is a directory", file))
+	} else if os.Geteuid() != 1001 {
+		// UID 1001 is the hardcoded uid for mirror
+		err := os.Chown(file, 1001, os.Getegid())
+		panicIfErr(err)
+	} else if fi.Mode().Perm() != 0644 {
+		err := os.Chmod(file, 0644)
+		panicIfErr(err)
+	}
+}
+
+func touchFiles(files ...string) {
+	for _, file := range files {
+		touchFile(file)
+	}
+}

merlin/logger/logger.go

@@ -1,4 +1,4 @@
-package common
+package logger
 
 import (
 	"log"
@@ -30,12 +30,12 @@ var levels = map[int]string{
 var outLogger = log.New(os.Stdout, "", log.LstdFlags)
 var errLogger = log.New(os.Stderr, "", log.LstdFlags)
 
-func OutLogger() *log.Logger {
-	return outLogger
+func OutLog(v ...interface{}) {
+	outLogger.Println(v...)
 }
 
-func ErrLogger() *log.Logger {
-	return errLogger
+func ErrLog(v ...interface{}) {
+	errLogger.Println(v...)
 }
 
 func NewLogger(name, file string) *Logger {
@@ -48,15 +48,9 @@ func NewLogger(name, file string) *Logger {
 }
 
 func (logger *Logger) Log(level int, v ...interface{}) {
-	if level == INFO {
-		outLogger.Println(append([]interface{}{"[" + logger.name + "]"}, v...))
-	} else if level == ERROR {
-		errLogger.Println(append([]interface{}{"[" + logger.name + "]"}, v...))
-	}
-
 	f, err := os.OpenFile(logger.file, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
 	if err != nil {
-		errLogger.Println(err.Error())
+		ErrLog(err.Error())
 	}
 	defer f.Close()
 
@@ -65,7 +59,7 @@ func (logger *Logger) Log(level int, v ...interface{}) {
 	args = append(args, v...)
 
 	logger.SetOutput(f)
-	logger.Println(v...)
+	logger.Println(args)
 }
 
 func (logger *Logger) Debug(v ...interface{}) {
@@ -73,6 +67,7 @@ func (logger *Logger) Debug(v ...interface{}) {
 }
 
 func (logger *Logger) Info(v ...interface{}) {
+	OutLog(append([]interface{}{"[" + logger.name + "]"}, v...))
 	logger.Log(INFO, v...)
 }
 
@@ -81,5 +76,6 @@ func (logger *Logger) Warning(v ...interface{}) {
 }
 
 func (logger *Logger) Error(v ...interface{}) {
+	ErrLog(append([]interface{}{"[" + logger.name + "]"}, v...))
 	logger.Log(ERROR, v...)
 }

merlin/merlin.go

@@ -1,153 +1,32 @@
 package main
 
 import (
-	"bytes"
-	"errors"
 	"fmt"
-	"io"
-	"log"
 	"net"
 	"os"
 	"os/signal"
-	"path/filepath"
-	"strings"
 	"syscall"
-	"text/tabwriter"
 	"time"
 
-	"git.csclub.uwaterloo.ca/public/merlin/common"
 	"golang.org/x/sys/unix"
-)
 
-var (
-	cfg            common.Config
-	outLogger      *log.Logger
-	errLogger      *log.Logger
-	repoMap        map[string]*common.Repo
-	repoIdx        int
-	numJobsRunning int
+	"git.csclub.uwaterloo.ca/public/merlin/arthur"
+	"git.csclub.uwaterloo.ca/public/merlin/config"
+	"git.csclub.uwaterloo.ca/public/merlin/logger"
+	"git.csclub.uwaterloo.ca/public/merlin/sync"
 )
 
-func getAndRunCommand(conn net.Conn) {
-	defer conn.Close()
-
-	var buf bytes.Buffer
-	_, err := io.Copy(&buf, conn)
-	if err != nil {
-		errLogger.Println(err.Error())
-		return
-	}
-
-	command := buf.String()
-	args := strings.Split(command, ":")
-	respondAndLogErr := func(msg string) {
-		outLogger.Println(msg)
-		conn.Write([]byte(msg))
-	}
-
-	if args[0] == "status" {
-		status := tabwriter.NewWriter(conn, 5, 5, 5, ' ', 0)
-		fmt.Fprintf(status, "Repository\tLast Synced\tNext Expected Sync\n")
-
-		// for time formating see https://pkg.go.dev/time#pkg-constants
-		for name, repo := range repoMap {
-			fmt.Fprintf(status, "%s\t%s\t%s\n",
-				name,
-				time.Unix(repo.State.LastAttemptStartTime, 0).Format(time.RFC1123),
-				time.Unix(repo.State.LastAttemptRunTime+int64(repo.Frequency), 0).Format(time.RFC1123),
-			)
-		}
-
-		status.Flush()
-	} else if args[0] == "sync" {
-		if len(args) != 2 {
-			respondAndLogErr("Could not parse sync command, forced sync fails.")
-			return
-		}
-
-		if repo, inMap := repoMap[args[1]]; inMap {
-			outLogger.Println("Attempting to force sync of " + repo.Name)
-			if repo.RunIfPossible() {
-				conn.Write([]byte("Forced sync for " + repo.Name))
-				numJobsRunning++
-			} else {
-				respondAndLogErr("Cannot force sync: " + repo.Name + ", already syncing.")
-			}
-		} else {
-			respondAndLogErr(args[1] + " is not tracked so cannot sync")
-		}
-	} else {
-		respondAndLogErr("Received unrecognized command: " + command)
-	}
-}
-
-func unixSockListener(connChan chan net.Conn, stopLisChan chan struct{}) {
-	// must remove cfg.SockPath otherwise get "bind: address already in use"
-	if filepath.Ext(cfg.SockPath) != ".sock" {
-		panic(fmt.Errorf("Socket file must end with .sock"))
-	} else if _, err := os.Stat(cfg.SockPath); err == nil {
-		if err := os.Remove(cfg.SockPath); err != nil {
-			panic(err)
-		}
-	} else if !errors.Is(err, os.ErrNotExist) {
-		panic(err)
-	}
-
-	ear, err := net.Listen("unix", cfg.SockPath)
-	if err != nil {
-		panic(err)
-	}
-	outLogger.Println("Listening to unix socket at " + cfg.SockPath)
-
-	go func() {
-		for {
-			// will exit when ear is closed
-			conn, err := ear.Accept()
-			if err != nil {
-				if ne, ok := err.(net.Error); ok && ne.Temporary() {
-					errLogger.Println("Accepted socket error: " + err.Error())
-					continue
-				}
-				errLogger.Println("Unhandlable socket error: " + err.Error())
-				return
-			}
-			connChan <- conn
-		}
-	}()
-
-	<-stopLisChan
-	ear.Close()
-}
-
-// We use a round-robin strategy. It's not the most efficient, but it's simple
-// (read: easy to understand) and guarantees each repo will eventually get a chance to run.
-func runAsManyAsPossible() {
-	repos := cfg.Repos
-	startIdx := repoIdx
-
-	for numJobsRunning < cfg.MaxJobs {
-		repo := repos[repoIdx]
-		if repo.RunIfPossible() {
-			numJobsRunning++
-		}
-		repoIdx = (repoIdx + 1) % len(repos)
-		if repoIdx == startIdx {
-			// we've come full circle
-			return
-		}
-	}
-}
-
 func main() {
-	outLogger = common.OutLogger()
-	errLogger = common.ErrLogger()
-
 	// check that merlin is run as mirror user
 	// check that mirror user has pid of 1001
 
-	doneChan := make(chan common.Result)
+	// receives a Result struct when a repo stops syncing
+	doneChan := make(chan config.SyncResult)
+	// closed when merlin is told to stop running
 	stopChan := make(chan struct{})
+	// receives a Conn when a client makes a connection to unix socket
 	connChan := make(chan net.Conn)
+	// signal channel to stop listening to unix socket
 	stopLisChan := make(chan struct{})
 
 	stopSig := make(chan os.Signal, 1)
@@ -157,24 +36,37 @@ func main() {
 
 	unix.Umask(002)
 
-	numJobsRunning = 0
+	numJobsRunning := 0
+	repoIdx := 0
 
 	loadConfig := func() {
-		cfg = common.GetConfig(doneChan, stopChan)
-		outLogger.Println("Loaded config:\n" + fmt.Sprintf("%+v\n", cfg))
-
-		repoMap = make(map[string]*common.Repo)
-		for _, repo := range cfg.Repos {
-			repoMap[repo.Name] = repo
-		}
+		config.LoadConfig(doneChan, stopChan)
+		logger.OutLog("Loaded config:\n" + fmt.Sprintf("%+v\n", config.Conf))
 
 		repoIdx = 0
-		go unixSockListener(connChan, stopLisChan)
+		go arthur.UnixSockListener(connChan, stopLisChan)
+	}
+	// We use a round-robin strategy. It's not the most efficient, but it's simple
+	// (read: easy to understand) and guarantees each repo will eventually get a chance to run.
+	runAsManyAsPossible := func() {
+		startIdx := repoIdx
+
+		for numJobsRunning < config.Conf.MaxJobs {
+			repo := config.Repos[repoIdx]
+			if sync.SyncIfPossible(repo) {
+				numJobsRunning++
+			}
+			repoIdx = (repoIdx + 1) % len(config.Repos)
+			if repoIdx == startIdx {
+				// we've come full circle
+				return
+			}
+		}
 	}
 
 	loadConfig()
-	// IsRunning must be false otherwise repo will never sync
-	for _, repo := range repoMap {
+	// ensure that IsRunning is false otherwise repo will never sync
+	for _, repo := range config.RepoMap {
 		repo.State.IsRunning = false
 	}
 	runAsManyAsPossible()
@@ -192,22 +84,27 @@ runLoop:
 			loadConfig()
 
 		case done := <-doneChan:
-			repoMap[done.Name].SyncCompleted(done.Exit)
+			sync.SyncCompleted(config.RepoMap[done.Name], done.Exit)
 			numJobsRunning--
 
 		case conn := <-connChan:
-			getAndRunCommand(conn)
+			// TODO: may want to split this into GetCommand and something else
+			// to make it more clear tha GetAndRunCommand returns true if
+			// it starts a sync
+			if arthur.GetAndRunCommand(conn) {
+				numJobsRunning--
+			}
 
 		case <-time.After(1 * time.Minute):
 		}
 		runAsManyAsPossible()
 	}
 
-	// give time for jobs to terminate before exiting
+	// give time for all jobs to terminate before exiting program
 	for {
 		select {
 		case done := <-doneChan:
-			repoMap[done.Name].SyncCompleted(done.Exit)
+			sync.SyncCompleted(config.RepoMap[done.Name], done.Exit)
 			numJobsRunning--
 
 		case <-time.After(1 * time.Second):

merlin/merlin_test.go

@@ -1,7 +0,0 @@
-package main
-
-import "testing"
-
-func TestSock1(t *testing.T) {
-
-}

merlin/sync/command.go

@@ -1,50 +1,51 @@
-package common
+package sync
 
 import (
 	"fmt"
 	"math/rand"
-	"os"
 	"strconv"
+
+	"git.csclub.uwaterloo.ca/public/merlin/config"
 )
 
-func (repo *Repo) buildRsyncHost() string {
+func buildRsyncHost(repo *config.Repo) string {
 	if repo.RsyncUser != "" {
 		repo.RsyncHost = repo.RsyncUser + "@" + repo.RsyncHost
 	}
 	return "rsync://" + repo.RsyncHost + "/" + repo.RsyncDir
 }
 
-func (repo *Repo) buildRsyncDaemonHost() string {
+func buildRsyncDaemonHost(repo *config.Repo) string {
 	if repo.RsyncUser != "" {
 		repo.RsyncHost = repo.RsyncUser + "@" + repo.RsyncHost
 	}
 	return repo.RsyncHost + "::" + repo.RsyncDir
 }
 
-func (repo *Repo) buildRsyncSSHHost() string {
+func buildRsyncSSHHost(repo *config.Repo) string {
 	if repo.RsyncUser != "" {
 		repo.RsyncHost = repo.RsyncUser + "@" + repo.RsyncHost
 	}
 	return repo.RsyncHost + ":" + repo.RsyncDir
 }
 
-func (repo *Repo) buildDownloadDir() string {
-	return repo.cfg.DownloadDir + "/" + repo.LocalDir
+func buildDownloadDir(repo *config.Repo) string {
+	return config.Conf.DownloadDir + "/" + repo.LocalDir
 }
 
-func (repo *Repo) CSCSyncApache() []string {
+func cscSyncApache(repo *config.Repo) []string {
 	args := []string{
 		"nice", "rsync", "-az", "--no-owner", "--no-group", "--delete", "--safe-links",
-		"--timeout=3600", "-4", "--address=" + repo.cfg.IPv4Address,
+		"--timeout=3600", "-4", "--address=" + config.Conf.IPv4Address,
 		"--exclude", ".~tmp~/",
 		"--quiet", "--stats", "--log-file=" + repo.RsyncLogFile,
 	}
-	args = append(args, repo.buildRsyncDaemonHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncDaemonHost(repo), buildDownloadDir(repo))
 
 	return args
 }
 
-func (repo *Repo) CSCSyncArchLinux() []string {
+func cscSyncArchLinux(repo *config.Repo) []string {
 
 	tempDir := "" // is this option even needed?
 
@@ -52,83 +53,83 @@ func (repo *Repo) CSCSyncArchLinux() []string {
 	args := []string{
 		"rsync", "-rtlH", "--safe-links", "--delete-after", "--timeout=600",
 		"--contimeout=60", "-p", "--delay-updates", "--no-motd",
-		"--temp-dir=" + tempDir, "--log-file=" + repo.RsyncLogFile, "--address=" + repo.cfg.IPv4Address,
+		"--temp-dir=" + tempDir, "--log-file=" + repo.RsyncLogFile, "--address=" + config.Conf.IPv4Address,
 	}
-	args = append(args, repo.buildRsyncHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncHost(repo), buildDownloadDir(repo))
 
 	return args
 
 }
 
-func (repo *Repo) CSCSyncBadPerms() []string {
+func cscSyncBadPerms(repo *config.Repo) []string {
 	args := []string{
 		"nice", "rsync", "-aH", "--no-owner", "--no-group", "--chmod=o=rX", "--delete",
-		"--timeout=3600", "-4", "--address=" + repo.cfg.IPv4Address,
+		"--timeout=3600", "-4", "--address=" + config.Conf.IPv4Address,
 		"--exclude", ".~tmp~/",
 		"--quiet", "--stats", "--log-file=" + repo.RsyncLogFile,
 	}
-	args = append(args, repo.buildRsyncDaemonHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncDaemonHost(repo), buildDownloadDir(repo))
 
 	return args
 }
 
 // TODO ceph
 
-func (repo *Repo) CSCSyncCDImage() []string {
+func cscSyncCDImage(repo *config.Repo) []string {
 	args := []string{
 		"nice", "rsync", "-aH", "--no-owner", "--no-group", "--delete",
-		"--timeout=3600", "-4", "--address=" + repo.cfg.IPv4Address,
+		"--timeout=3600", "-4", "--address=" + config.Conf.IPv4Address,
 		"--exclude", ".*/", "--quiet", "--stats", "--log-file=" + repo.RsyncLogFile,
 	}
-	args = append(args, repo.buildRsyncDaemonHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncDaemonHost(repo), buildDownloadDir(repo))
 
 	return args
 }
 
-func (repo *Repo) CSCSyncChmod() []string {
+func cscSyncChmod(repo *config.Repo) []string {
 	args := []string{
 		"nice", "rsync", "-aH", "--no-owner", "--no-group", "--delete-after", "--delay-updates", "--safe-links",
-		"--timeout=3600", "-4", "--address=" + repo.cfg.IPv4Address,
+		"--timeout=3600", "-4", "--address=" + config.Conf.IPv4Address,
 		"--exclude", ".~tmp~/", "--quiet", "--stats", "--log-file=" + repo.RsyncLogFile,
 		"--chmod=u=rwX,go=rX",
 	}
-	args = append(args, repo.buildRsyncHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncHost(repo), buildDownloadDir(repo))
 
 	return args
 }
 
-func (repo *Repo) CSCSyncDebian() []string {
+func cscSyncDebian(repo *config.Repo) []string {
 
 	// sync /pool
 	args := []string{"nice", "rsync", "-rlHtvp",
 		"--exclude", ".~tmp~/", "--timeout=3600", "-4",
-		"--address=" + repo.cfg.IPv4Address,
+		"--address=" + config.Conf.IPv4Address,
 	}
 	// $RSYNC_HOST::$RSYNC_DIR/pool/ $TO/pool/ >> $LOGFILE 2>&1
 	return args
 }
 
-func (repo *Repo) CSCSyncDebianCD() []string {
+func cscSyncDebianCD(repo *config.Repo) []string {
 
 	// this is basically the same as CSCSyncDebian, except it has an extra --exclude
 	args := []string{"nice", "rsync", "-rlHtvp", "--delete",
 		"--exclude", ".~tmp~/", "--timeout=3600", "-4",
-		"--address=" + repo.cfg.IPv4Address,
+		"--address=" + config.Conf.IPv4Address,
 		// "--exclude", "Archive-Update-in-Progress-${HOSTNAME}"
 	}
 	// $RSYNC_HOST::$RSYNC_DIR $TO >> $LOGFILE 2>&1
 	return args
 }
 
-func (repo *Repo) CSCSyncGentoo() []string {
+func cscSyncGentoo(repo *config.Repo) []string {
 	repo.RsyncUser = "gentoo"
 	repo.PasswordFile = "gentoo-distfiles"
-	return repo.CSCSyncStandard()
+	return cscSyncStandard(repo)
 }
 
 // TODO s3
 
-func (repo *Repo) CSCSyncSSH() []string {
+func cscSyncSSH(repo *config.Repo) []string {
 
 	args := []string{
 		"rsync", "-aH", "--no-owner", "--no-group", "--delete",
@@ -138,39 +139,39 @@ func (repo *Repo) CSCSyncSSH() []string {
 	}
 	// not sure if we should be assuming ssh identity file is the password file
 	args = append(args, "-e", fmt.Sprintf("'ssh -i %s'", repo.PasswordFile))
-	args = append(args, repo.buildRsyncSSHHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncSSHHost(repo), buildDownloadDir(repo))
 
 	return args
 }
 
-func (repo *Repo) CSCSyncStandard() []string {
+func cscSyncStandard(repo *config.Repo) []string {
 	args := []string{
 		"nice", "rsync", "-aH", "--no-owner", "--no-group", "--delete-after",
-		"--delay-updates", "--safe-links", "--timeout=3600", "-4", "--address=" + repo.cfg.IPv4Address,
+		"--delay-updates", "--safe-links", "--timeout=3600", "-4", "--address=" + config.Conf.IPv4Address,
 		"--exclude", ".~tmp~/", "--quiet", "--stats", "--log-file=" + repo.RsyncLogFile,
 	}
 	if repo.PasswordFile != "" {
-		filename := repo.cfg.PasswordDir + "/" + repo.PasswordFile
+		filename := config.Conf.PasswordDir + "/" + repo.PasswordFile
 		args = append(args, "--password-file", filename)
 	}
-	args = append(args, repo.buildRsyncHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncHost(repo), buildDownloadDir(repo))
 
 	return args
 }
 
-func (repo *Repo) CSCSyncStandardIPV6() []string {
+func cscSyncStandardIPV6(repo *config.Repo) []string {
 	args := []string{
 		"nice", "rsync", "-aH", "--no-owner", "--no-group", "--delete-after",
-		"--delay-updates", "--safe-links", "--timeout=3600", "-6", "--address=" + repo.cfg.IPv4Address,
+		"--delay-updates", "--safe-links", "--timeout=3600", "-6", "--address=" + config.Conf.IPv4Address,
 		"--exclude", ".~tmp~/", "--quiet", "--stats", "--log-file=" + repo.RsyncLogFile,
 	}
-	args = append(args, repo.buildRsyncDaemonHost(), repo.buildDownloadDir())
+	args = append(args, buildRsyncDaemonHost(repo), buildDownloadDir(repo))
 
 	return args
 }
 
 // for testing, to be removed later
-func (repo *Repo) CSCSyncDummy() []string {
+func cscSyncDummy(repo *config.Repo) []string {
 
 	sleepDur := strconv.FormatInt(rand.Int63n(10)+5, 10)
 	args := []string{"sleep", sleepDur}
@@ -179,7 +180,7 @@ func (repo *Repo) CSCSyncDummy() []string {
 }
 
 // executes a particular sync job depending on repo.SyncType.
-func (repo *Repo) getSyncCommand() []string {
+func getSyncCommand(repo *config.Repo) []string {
 	/*
 		# scripts used by merlin.py
 		csc-sync-debian
@@ -208,78 +209,38 @@ func (repo *Repo) getSyncCommand() []string {
 	switch repo.SyncType {
 
 	case "csc-sync-apache":
-		return repo.CSCSyncApache()
+		return cscSyncApache(repo)
 	case "csc-sync-archlinux":
-		return repo.CSCSyncArchLinux()
+		return cscSyncArchLinux(repo)
 	case "csc-sync-badperms":
-		return repo.CSCSyncBadPerms()
+		return cscSyncBadPerms(repo)
 	case "csc-sync-cdimage":
-		return repo.CSCSyncCDImage()
+		return cscSyncCDImage(repo)
 	// case "csc-sync-ceph":
-	// 	return repo.CSCSyncCeph()
+	// 	return cscSyncCeph(repo)
 	case "csc-sync-chmod":
-		return repo.CSCSyncChmod()
+		return cscSyncChmod(repo)
 	case "csc-sync-debian":
-		return repo.CSCSyncDebian()
+		return cscSyncDebian(repo)
 	case "csc-sync-debian-cd":
-		return repo.CSCSyncDebianCD()
+		return cscSyncDebianCD(repo)
 	case "csc-sync-gentoo":
-		return repo.CSCSyncGentoo()
+		return cscSyncGentoo(repo)
 	// case "csc-sync-s3":
-	// 	return repo.CSCSyncS3()
+	// 	return cscSyncS3(repo)
 	case "csc-sync-ssh":
-		return repo.CSCSyncSSH()
+		return cscSyncSSH(repo)
 	case "csc-sync-standard":
-		return repo.CSCSyncStandard()
+		return cscSyncStandard(repo)
 	case "csc-sync-standard-ipv6":
-		return repo.CSCSyncStandardIPV6()
+		return cscSyncStandardIPV6(repo)
 		// case "csc-sync-wget":
-		// 	return repo.CSCSyncWget()
+		// 	return cscSyncWget(repo)
 	case "csc-sync-dummy":
-		return repo.CSCSyncDummy()
+		return cscSyncDummy(repo)
 	default:
 		repo.Logger.Error("Unrecognized sync type", "'"+repo.SyncType+"'")
 	}
 
 	return []string{}
 }
-
-func (repo *Repo) StartSyncJob() {
-	status := FAILURE
-	defer func() {
-		repo.DoneChan <- Result{
-			Name: repo.Name,
-			Exit: status,
-		}
-	}()
-
-	localDir := repo.buildDownloadDir()
-	err := os.MkdirAll(localDir, 0775)
-	if err != nil {
-		err = fmt.Errorf("Could not create directory %s: %w", localDir, err)
-		// I'm not sure if logger can handle error so just use the string?
-		repo.Logger.Error(err.Error())
-		return
-	}
-
-	args := repo.getSyncCommand()
-	if repo.PasswordFile != "" {
-		filename := repo.cfg.PasswordDir + "/" + repo.PasswordFile
-		args = append(args, "--password-file", filename)
-	}
-	args = append(args, repo.buildRsyncHost(), localDir)
-
-	ch := SpawnProcess(repo, args)
-	if ch == nil {
-		// SpawnProcess will have already logged error
-		return
-	}
-	cmd := <-ch
-	switch cmd.ProcessState.ExitCode() {
-	case 0:
-		status = SUCCESS
-	case -1:
-		status = TERMINATED
-		// default is already FAILURE
-	}
-}

merlin/sync/command_test.go

@@ -0,0 +1 @@
+package sync

merlin/sync/interface.go

@@ -0,0 +1,59 @@
+package sync
+
+import (
+	"fmt"
+	"time"
+
+	"git.csclub.uwaterloo.ca/public/merlin/config"
+)
+
+// start sync job for this repo if more than repo.Frequency seconds have elapsed since its last job
+// and is not currently running.
+// returns true iff a job is started.
+func SyncIfPossible(repo *config.Repo) bool {
+	// Change to SyncIfPossible
+	if repo.State.IsRunning {
+		return false
+	}
+
+	curTime := time.Now().Unix()
+	if curTime-repo.State.LastAttemptStartTime > int64(repo.Frequency) {
+		repo.State.IsRunning = true
+		repo.State.LastAttemptStartTime = curTime
+		repo.SaveState()
+		repo.Logger.Info(fmt.Sprintf("Repo %s has started syncing", repo.Name))
+		go startSync(repo)
+		return true
+	}
+	return false
+}
+
+// update the repo state with the last attempt time and exit now that the job is done
+func SyncCompleted(repo *config.Repo, exit int) {
+	repoState := repo.State
+	syncTook := time.Now().Unix() - repoState.LastAttemptStartTime
+	nextSync := repo.MaxTime - int(syncTook)
+	if nextSync < 0 {
+		nextSync = 0
+	}
+
+	repoState.IsRunning = false
+	repoState.LastAttemptExit = exit
+	repoState.LastAttemptRunTime = syncTook
+
+	var exitStr string
+	switch exit {
+	case config.SUCCESS:
+		exitStr = "completed"
+	case config.TERMINATED:
+		exitStr = "terminated"
+	default:
+		exitStr = "failed"
+	}
+	repo.SaveState()
+	repo.Logger.Info(fmt.Sprintf("Sync "+exitStr+" after running for %d seconds, will run again in %d seconds", syncTook, nextSync))
+	if exit == config.SUCCESS {
+		// it is possible that the zfssync from the last repo sync is still running is that fine?
+		go zfsSync(repo)
+	}
+}

merlin/sync/sync.go

@@ -1,10 +1,13 @@
-package common
+package sync
 
 import (
 	"fmt"
+	"os"
 	"os/exec"
 	"syscall"
 	"time"
+
+	"git.csclub.uwaterloo.ca/public/merlin/config"
 )
 
 // SpawnProcess spawns a child process for the given repo. The process will
@@ -12,7 +15,7 @@ import (
 // runs for longer than the repo's MaxTime.
 // It returns a channel through which a Cmd will be sent once it has finished,
 // or nil if it was unable to start a process.
-func SpawnProcess(repo *Repo, args []string) (ch <-chan *exec.Cmd) {
+func spawnSyncProcess(repo *config.Repo, args []string) (ch <-chan *exec.Cmd) {
 	// startTime and time took will be handled in common.go by SyncExit
 	cmd := exec.Command(args[0], args[1:]...)
 
@@ -68,3 +71,58 @@ func SpawnProcess(repo *Repo, args []string) (ch <-chan *exec.Cmd) {
 	}()
 	return
 }
+
+func startSync(repo *config.Repo) {
+	status := config.FAILURE
+	defer func() {
+		repo.DoneChan <- config.SyncResult{
+			Name: repo.Name,
+			Exit: status,
+		}
+	}()
+
+	localDir := buildDownloadDir(repo)
+	err := os.MkdirAll(localDir, 0775)
+	if err != nil {
+		err = fmt.Errorf("Could not create directory %s: %w", localDir, err)
+		// I'm not sure if logger can handle error so just use the string?
+		repo.Logger.Error(err.Error())
+		return
+	}
+
+	args := getSyncCommand(repo)
+	if repo.PasswordFile != "" {
+		filename := config.Conf.PasswordDir + "/" + repo.PasswordFile
+		args = append(args, "--password-file", filename)
+	}
+	args = append(args, buildRsyncHost(repo), localDir)
+
+	ch := spawnSyncProcess(repo, args)
+	if ch == nil {
+		// SpawnProcess will have already logged error
+		return
+	}
+	cmd := <-ch
+	switch cmd.ProcessState.ExitCode() {
+	case 0:
+		status = config.SUCCESS
+	case -1:
+		status = config.TERMINATED
+		// default is already FAILURE
+	}
+}
+
+func zfsSync(repo *config.Repo) {
+	out, err := exec.Command("/home/mirror/bin/zfssync", repo.Name).CombinedOutput()
+	if err != nil {
+		repo.Logger.Error(err)
+	} else {
+		f, err := os.OpenFile(repo.ZfssyncLogFile, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
+		if err != nil {
+			repo.Logger.Error(err.Error())
+		} else {
+			f.Write(out)
+		}
+
+	}
+}