tidy up logging

config.go

@@ -3,7 +3,6 @@ package main
 import (
 	"encoding/json"
 	"fmt"
-	"log"
 	"os"
 
 	"github.com/adhocore/jsonc"
@@ -32,7 +31,7 @@ func (config *Config) load() error {
 
 	homeDir, err := os.UserHomeDir()
 	if err != nil {
-		log.Println("could not get home directory!")
+		elog.Println("could not get home directory!")
 		return err
 	}
 
@@ -43,25 +42,25 @@ func (config *Config) load() error {
 			defaultConfig := makeDefaultConfig()
 			defaultConfigJSON, err := json.MarshalIndent(defaultConfig, "", "")
 			if err != nil {
-				log.Println("could not encode default config!")
+				elog.Println("could not encode default config!")
 				return err
 			}
 			//TODO: make parent directories if they don't exist
 			err = os.Mkdir(homeDir+"/.config", 755)
 			if err != nil && !os.IsExist(err) {
-				log.Println("could not create .config directory", err)
+				elog.Println("could not create .config directory", err)
 				return err
 			}
 			err = os.Mkdir(configDir, 755)
 			if err != nil && !os.IsExist(err) {
-				log.Println("could not create .config/gopaper directory")
+				elog.Println("could not create .config/gopaper directory")
 				return err
 			}
 
 			file, err := os.Create(configDir + "config.jsonc")
 			defer file.Close()
 			if err != nil {
-				log.Println("could not create config file!")
+				elog.Println("could not create config file!")
 				return err
 			}
 			file.Write(defaultConfigJSON)
@@ -72,7 +71,7 @@ func (config *Config) load() error {
 		configRaw = j.Strip(configRaw)
 		err = json.Unmarshal(configRaw, &config)
 		if err != nil {
-			log.Println("Couldn't unmarshal config!")
+			elog.Println("Couldn't unmarshal config!")
 			return err
 		}
 

image.go

@@ -37,7 +37,6 @@ func hexToHSL(string) [3]int {
 func pickRandomImage(dir string) (string, error) {
 
 	dir = config.ImagesDir + dir
-	log.Printf("getting random file from %v\n", dir)
 	randomImg, filename, _ := getRandomFile(dir)
 	filenameNoExt := strings.TrimSuffix(filename, filepath.Ext(filename))
 
@@ -50,13 +49,13 @@ func pickRandomImage(dir string) (string, error) {
 	if !fileExists {
 		img, err := loadImage(randomImg)
 		if err != nil {
-			log.Printf("failed to load image %v", randomImg)
+			elog.Printf("failed to load image %v", randomImg)
 			return "", err
 		}
 		dst := processImage(img, config)
 		saveImage(curr, dst)
 	} else {
-		log.Println("file already exists in cache. skipping image processing")
+		log.Printf("file %v already exists in cache. skipping image processing\n", filename)
 	}
 	return curr, nil
 }

main.go

@@ -1,12 +1,11 @@
 package main
 
 import (
-	"bytes"
-	"encoding/binary"
 	"flag"
 	"log"
 	"os"
 	"os/exec"
+	"strconv"
 	"sync"
 )
 
@@ -15,43 +14,23 @@ var config Config
 const sockfile = "/tmp/gopaper.sock"
 const pidfilePath = "/tmp/gopaper.pid"
 
+var clog = log.New(os.Stdout, "## ", 0)
+var elog = log.New(os.Stdout, "ERROR: ", 3)
+
 func main() {
 	//SETUP FLAGS
 	var debugFlag = flag.Bool("debug", false, "help message for flag n")
 	flag.Parse()
 
-	//INITIALIZE CONFIG
+	clog.Println("Welcome to GoPaper!")
+
+	//INIT CONFIG
 	err := config.load()
 	if err != nil {
-		log.Println("unable to initialize config", err)
+		elog.Println("unable to initialize config", err)
 	}
-
+	handleProcesses()
-	//SETUP LOGGER
+	setupLogging(*debugFlag)
-	log.SetFlags(log.LstdFlags | log.Lshortfile)
-	if *debugFlag {
-		logfile, err := openLogfile()
-		if err != nil {
-			log.Println("failed to load config", err)
-			cleanExit(1)
-		}
-		log.SetOutput(logfile)
-	}
-	log.SetFlags(log.LstdFlags | log.Lshortfile | log.Lmicroseconds)
-	log.Println("Welcome to GoPaper!")
-
-	killPrevProc()
-	//create new pidfile
-	pid := os.Getpid()
-	pidfile, err := os.Create(pidfilePath)
-	if err != nil {
-		log.Println("error trying to create pidfile:", err)
-		cleanExit(1)
-	}
-	buf := new(bytes.Buffer)
-	err = binary.Write(buf, binary.LittleEndian, pid)
-	if err != nil {
-	}
-	pidfile.Write(buf.Bytes())
 
 	var waitGroup sync.WaitGroup
 	waitGroup.Add(1)
@@ -98,7 +77,7 @@ func cleanExit(code int) {
 
 	err := os.Remove(sockfile)
 	if err != nil && !os.IsNotExist(err) {
-		log.Printf("unable to remove sockfile at %v. Error: %v\n", sockfile, err)
+		elog.Printf("unable to remove sockfile at %v. Error: %v\n", sockfile, err)
 	} else if !os.IsNotExist(err) {
 		log.Println("sockfile removed")
 	} else {
@@ -107,7 +86,7 @@ func cleanExit(code int) {
 
 	err = os.Remove(pidfilePath)
 	if err != nil && !os.IsNotExist(err) {
-		log.Printf("unable to remove pidfile at %v. Error: %v\n", pidfilePath, err)
+		elog.Printf("unable to remove pidfile at %v. Error: %v\n", pidfilePath, err)
 	} else if !os.IsNotExist(err) {
 		log.Println("pidfile removed")
 	} else {
@@ -124,21 +103,51 @@ func killPrevProc() error {
 	//if it does, kill the process and delete the pidfile
 	prexPid, err := os.ReadFile(pidfilePath)
 	if err != nil {
-		log.Println("unable to read pre-existing pidfile", err)
+		elog.Println("unable to read pre-existing pidfile", err)
 		return err
 	}
 	//kill process
-	//BUG: kill command doesn't work. prexPid == []
+	err = exec.Command("kill", string(prexPid)).Run()
-	err = exec.Command("kill", "-9", string(prexPid)).Run()
 	if err != nil {
-		log.Printf("unable to kill process %v\n", string(prexPid))
+		elog.Printf("Error attempting to kill process %v: %v\n", string(prexPid), err)
-		return err
 	}
 	//remove pidfile
 	err = os.Remove(pidfilePath)
-	if err != nil {
+	if err != nil && !os.IsNotExist(err) {
-		log.Printf("unable to remove pidfile %v\n", pidfilePath)
+		elog.Printf("unable to remove pidfile at %v. Error: %v\n", pidfilePath, err)
-		return err
 	}
 	return nil
 }
+func handleProcesses() {
+	err := killPrevProc()
+	if err != nil {
+		elog.Println("error attempting to kill pre-existing process: ", err)
+		os.Exit(1)
+	}
+	//create new pidfile
+	pid := strconv.FormatInt(int64(os.Getpid()), 10)
+	pidfile, err := os.Create(pidfilePath)
+	if err != nil {
+		elog.Println("error trying to create pidfile:", err)
+		os.Exit(1)
+	}
+	pidfile.WriteString(pid)
+
+}
+
+func setupLogging(debug bool) {
+
+	//SETUP LOGGERS
+	if debug {
+		logfile, err := openLogfile()
+		if err != nil {
+			elog.Println("failed to load config", err)
+			os.Exit(1)
+		}
+		log.SetOutput(logfile)
+		clog.SetOutput(logfile)
+		elog.SetOutput(logfile)
+	}
+	elog.SetFlags(log.LstdFlags | log.Lshortfile)
+	log.SetFlags(log.LstdFlags)
+}

slideshow.go

@@ -16,11 +16,12 @@ func slideshow(ch <-chan string) {
 
 	go func() {
 		for {
-			err := setRandomWallpaper(dir)
+			img, err := setRandomWallpaper(dir)
 			if err != nil {
 				fmt.Printf("Failed to set random wallpaper from directory %v.", dir)
 				panic(err)
 			}
+			log.Printf("set %v as wallpaper\n", img)
 			select {
 			case dir = <-ch:
 				log.Println("directory set!")
@@ -33,10 +34,10 @@ func slideshow(ch <-chan string) {
 	}()
 }
 
-func setRandomWallpaper(dir string) error {
+func setRandomWallpaper(dir string) (string, error) {
 	img, err := pickRandomImage(dir)
 	if err != nil {
-		return err
+		return "", err
 	}
 
 	desktopEnv, bool := os.LookupEnv("DESKTOP_SESSION")
@@ -53,5 +54,5 @@ func setRandomWallpaper(dir string) error {
 		mode = ""
 	}
 
-	return wallutils.SetWallpaperCustom(img, mode, false)
+	return img, wallutils.SetWallpaperCustom(img, mode, false)
 }