I'm bad at commits...

main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"encoding/json"
 	"flag"
+	"fmt"
 	"html/template"
 	"io/ioutil"
 	"log"
@@ -12,7 +13,6 @@ import (
 	"net/url"
 	"os"
 	"regexp"
-	"strconv"
 	"strings"
 	"time"
 
@@ -22,20 +22,6 @@ import (
 	"github.com/patrickmn/go-cache"
 )
 
-type config struct {
-	addr       string
-	domain     string
-	dumpFile   string
-	path       string
-	proto      string
-	hostSuf    string
-	listenAddr string
-	port       int
-	urlSize    int
-	version    bool
-	templates  *template.Template
-}
-
 type body struct {
 	FullHeader bool
 	IsGhost    bool
@@ -52,74 +38,19 @@ const (
 	letterIdxBits = 6                                                                // 6 bits to represent a letter index
 	letterIdxMask = 1<<letterIdxBits - 1                                             // All 1-bits, as many as letterIdxBits
 	letterIdxMax  = 63 / letterIdxBits                                               // # of letter indices fitting in 63 bits
-	appVersion    = "1.2.1"
+	appVersion    = "1.3.0"
 )
 
 var (
-	cfg  config
+	// tiny entropy pool
 	src = rand.NewSource(time.Now().UnixNano())
-	pool = cache.New(240*time.Hour, 1*time.Hour)
+	// KV memory DB
+	pool *cache.Cache
+	// Error codes
+	errBadRequest = fmt.Errorf("Bad Request")
+	errNotFound   = fmt.Errorf("Not Found")
 )
 
-func init() {
-	flag.StringVar(&cfg.addr, "addr", "localhost", "Address to listen for connections")
-	flag.StringVar(&cfg.domain, "domain", "localhost", "Domain to write to the URLs")
-	flag.StringVar(&cfg.dumpFile, "dump", "urls.json", "Path to the file to dump the kv db")
-	flag.StringVar(&cfg.path, "path", "", "Path to the base URL (https://localhost/PATH/... remember to append a / at the end")
-	flag.StringVar(&cfg.proto, "proto", "https", "proto to the base URL (HTTPS://localhost/path/... no real https here just to set the url (for like a proxy offloading https")
-	flag.IntVar(&cfg.port, "port", 8080, "Port to listen for connections")
-	flag.IntVar(&cfg.urlSize, "urlsize", 10, "Define the size of the shortened String, default 10")
-	flag.BoolVar(&cfg.version, "v", false, "prints current version")
-	flag.Parse()
-
-	if cfg.version {
-		log.SetFlags(0)
-		log.Println(appVersion)
-		os.Exit(0)
-	}
-
-	if cfg.port > 65535 || cfg.port < 1 {
-		log.Fatalln("Invalid port number")
-	}
-	if cfg.path != "" && !strings.HasSuffix(cfg.path, "/") {
-		cfg.path = cfg.path + "/"
-	}
-
-	if cfg.port != 80 && cfg.proto == "http" {
-		cfg.hostSuf = ":" + strconv.Itoa(cfg.port) + "/"
-	} else if cfg.port != 443 && cfg.proto == "https" {
-		cfg.hostSuf = ":" + strconv.Itoa(cfg.port) + "/"
-	} else if cfg.port == 443 || cfg.port == 80 {
-		cfg.hostSuf = "/"
-	}
-
-	ip := net.ParseIP(cfg.addr)
-	if ip != nil {
-		cfg.listenAddr = ip.String() + ":" + strconv.Itoa(cfg.port)
-	} else {
-		if govalidator.IsDNSName(cfg.addr) {
-			cfg.listenAddr = cfg.addr + ":" + strconv.Itoa(cfg.port)
-		} else {
-			log.Fatalln("Invalid ip address")
-		}
-	}
-
-	if !govalidator.IsDNSName(cfg.domain) {
-		log.Fatalln("Invalid domain address")
-	}
-
-	cfg.templates = template.Must(template.ParseFiles("templates/response.html"))
-}
-
-func (c config) index(w http.ResponseWriter, r *http.Request) {
-	b := body{
-		HasForm: true,
-		Line1:   "Welcome to Short, the simple URL shortener,",
-		Line2:   "Type an URL below to shorten it",
-	}
-	c.templates.Execute(w, b)
-}
-
 // get executes the GET command
 func get(key string) (string, bool) {
 	value, status := pool.Get(key)
@@ -134,76 +65,42 @@ func set(key, suffix string) {
 	pool.Set(suffix, key, 0)
 }
 
-// redirect reads the key from the requests url (GET /key) searches the
+// redirect receives a key searches the kv database for it and if
-// kv database for it and if found redirects the user to value, if not
+// found returns the value, or a error if not found
-// found return a 404.
+func redirect(k string) (string, error) {
-func (c config) redirect(w http.ResponseWriter, r *http.Request) {
-	vals := mux.Vars(r)
-	key := vals["key"]
-	b := body{
-		FullHeader: true,
-		IsGhost:    true,
-		HasForm:    true,
-		H1:         "404",
-		H3:         "page not found",
-		Line1:      "Boo, looks like this ghost stole this page!",
-		Line2:      "But you can type an URL below to shorten it",
-	}
-	if c.path != "" {
-		key = strings.Replace(key, c.path, "", 1)
-	}
 	rgx, _ := regexp.Compile("[a-zA-Z0-9]+")
-	key = rgx.FindString(key)
+	key := rgx.FindString(k)
 	key, status := get(key)
 	if !status {
-		w.WriteHeader(http.StatusNotFound)
+		return "", errNotFound
-		c.templates.Execute(w, b)
-		return
 	}
 	u, _ := url.Parse(key)
 	if u.Scheme == "" {
 		u.Scheme = "https"
 	}
-	http.Redirect(w, r, u.String(), http.StatusFound)
+	return u.String(), nil
 }
 
-// shortner reads url from a POST request, validates the url, generate a
+// shortener receive a url, validates the url, generate a random suffix string
-// random suffix string of urlSize size, checks if the suffix string is
+// of urlSize size, checks if the suffix string is ensure on the kv database
-// unique on the kv database and if not unique regenerates it and checks again,
+// and then writes the kv pair (suffix, url) to the database, returning the suffix
-// then if writes the kv pair suffix, url to the database and return the
+func shortener(u string, s int) (string, error) {
-// shortened url to the user
+	var su string
-func (c config) shortner(w http.ResponseWriter, r *http.Request) {
+	if !govalidator.IsURL(u) {
-	if !govalidator.IsURL(r.FormValue("url")) {
+		return su, errBadRequest
-		b := body{
-			FullHeader: true,
-			IsGhost:    true,
-			HasForm:    true,
-			H1:         "400",
-			H3:         "bad request",
-			Line1:      "Boo, looks like this ghost stole this page!",
-			Line2:      "But you can type an URL below to shorten it",
 	}
-		w.WriteHeader(http.StatusBadRequest)
+	pu, _ := url.Parse(u)
-		c.templates.Execute(w, b)
-		return
-	}
-	u, _ := url.Parse(r.FormValue("url"))
-	suffix := randStringBytesMaskImprSrc(c.urlSize)
 
 	for {
-		_, status := get(suffix)
+		su = randStringBytesMaskImprSrc(s)
+		_, status := get(su)
 		if !status {
 			break
 		}
-		suffix = randStringBytesMaskImprSrc(c.urlSize)
 	}
-	set(u.String(), suffix)
+
-	shortend := c.proto + "://" + c.domain + c.hostSuf + c.path + suffix
+	set(pu.String(), su)
-	b := body{
+	return su, nil
-		IsLink: true,
-		Line1:  shortend,
-	}
-	c.templates.Execute(w, b)
 }
 
 // randStringBytesMaskImprSrc Generate random string of n size
@@ -224,108 +121,211 @@ func randStringBytesMaskImprSrc(n int) string {
 	return string(b)
 }
 
-// internalError receives a http.ResponseWriter, msg and error and
+func internalError(msg string, err error) body {
-// return a internal error page with http code 500 to the user
+	log.Println(err)
-func (c config) internalError(w http.ResponseWriter, msg string, err error) {
+	return body{
-	b := body{
 		FullHeader: true,
 		IsGhost:    true,
 		HasForm:    true,
 		H1:         "500",
-		H3:         "internal erver error",
+		H3:         msg,
 		Line1:      "Boo, the ghost is broken :(",
 		Line2:      "His last words where: " + err.Error(),
 	}
-	log.Println(err)
-	w.WriteHeader(http.StatusInternalServerError)
-	c.templates.Execute(w, b)
 }
 
-// itemsCount returns the number of kv pairs on the in meomry database
+// loadFromFile loads kv pairs from the dumpFile json to the in memory database
-func (c config) itemsCount(w http.ResponseWriter, r *http.Request) {
+func loadFromFile(file string, e, c int) (int, error) {
-	w.Write(
+	dumpObj := make(map[string]cache.Item)
-		[]byte(
+	jsonFile, err := ioutil.ReadFile(file)
-			strconv.Itoa(
-				pool.ItemCount(),
-			),
-		),
-	)
-}
-
-// itemsDump returns a json with all the kv pairs on the in memory database
-func (c config) itemsDump(w http.ResponseWriter, r *http.Request) {
-	dumpObj, err := json.Marshal(
-		pool.Items(),
-	)
 	if err != nil {
-		c.internalError(w, "Unable to dump key value db: ", err)
+		return 0, err
 	}
-	w.Write(
-		[]byte(dumpObj),
-	)
-}
 
-// itemsFromFile loads kv pairs from the dumpFile json to the in memory database
+	err = json.Unmarshal([]byte(jsonFile), &dumpObj)
-func (c config) itemsFromFile(w http.ResponseWriter, r *http.Request) {
-	jsonFile, err := ioutil.ReadFile(c.dumpFile)
-	var dumpObj map[string]cache.Item
-	json.Unmarshal([]byte(jsonFile), &dumpObj)
 	if err != nil {
-		c.internalError(w, "Cannot open file "+c.dumpFile+": ", err)
+		return 0, err
-		return
 	}
-	pool = cache.NewFrom(240*time.Hour, 1*time.Hour, dumpObj)
+
-	b := body{
+	pool = cache.NewFrom(time.Duration(e)*time.Hour, time.Duration(c)*time.Hour, dumpObj)
-		Line1: "Imported " + strconv.Itoa(len(dumpObj)) + " items to the DB",
+	return len(dumpObj), err
-	}
-	c.templates.Execute(w, b)
 }
 
 // itemsFromPost loads kv pairs from a json POST to the in memory database
-func (c config) itemsFromPost(w http.ResponseWriter, r *http.Request) {
+func loadFromJSON(j []byte, e, c int) (int, error) {
-	decoder := json.NewDecoder(r.Body)
+	dumpObj := make(map[string]cache.Item)
-	var dumpObj map[string]cache.Item
+	err := json.Unmarshal(j, &dumpObj)
-	err := decoder.Decode(&dumpObj)
 	if err != nil {
-		c.internalError(w, "Cannot parse JSON: ", err)
+		return 0, err
-		return
 	}
-	pool = cache.NewFrom(240*time.Hour, 1*time.Hour, dumpObj)
+
-	b := body{
+	pool = cache.NewFrom(time.Duration(e)*time.Hour, time.Duration(c)*time.Hour, dumpObj)
-		Line1: "Imported " + strconv.Itoa(len(dumpObj)) + " items to the DB",
+	return len(dumpObj), nil
-	}
-	c.templates.Execute(w, b)
 }
 
-// itemsDumpToFile dumps the kv pairs from the in memory database to the dumpFile
+// dumpDbToFile dumps the kv pairs from the in memory database to file
-func (c config) itemsDumpToFile(w http.ResponseWriter, r *http.Request) {
+func dumpDbTOFile(file string) (int, error) {
-	dumpObj, _ := json.Marshal(
+	i := pool.Items()
-		pool.Items(),
+	dumpObj, _ := json.Marshal(i)
-	)
+	return len(i), ioutil.WriteFile(file, dumpObj, 0644)
-	err := ioutil.WriteFile(c.dumpFile, dumpObj, 0644)
-	if err != nil {
-		c.internalError(w, "Failed to open json file: ", err)
-		return
-	}
-	b := body{
-		Line1: "Imported " + "Dump writen to: " + c.dumpFile,
-	}
-	c.templates.Execute(w, b)
 }
 
 func main() {
+	var (
+		addr       = flag.String("addr", "localhost", "Address to listen for connections")
+		domain     = flag.String("domain", "localhost", "Domain to write to the URLs")
+		dumpFile   = flag.String("dump", "urls.json", "Path to the file to dump the kv db")
+		path       = flag.String("path", "", "Path to the base URL (https://localhost/PATH/...")
+		proto      = flag.String("proto", "https", "proto to the base URL (HTTPS://localhost/path/... no real https here just to set the url (for like a proxy offloading https")
+		port       = flag.Int("port", 8080, "Port to listen for connections")
+		urlSize    = flag.Int("urlsize", 10, "Define the size of the shortened String, default 10")
+		exp        = flag.Int("exp", 240, "Default expiration time in hours, default 240")
+		cleanup    = flag.Int("cleanup", 1, "Cleanup interval in hours, default 1")
+		version    = flag.Bool("v", false, "prints current version")
+		listenAddr string
+	)
 
+	flag.Parse()
+
+	if *version {
+		fmt.Println(appVersion)
+		os.Exit(0)
+	}
+
+	if *port > 65535 || *port < 1 {
+		log.Fatalln("Invalid port number")
+	}
+	if *path != "" && !strings.HasSuffix(*path, "/") {
+		*path = *path + "/"
+	}
+
+	ip := net.ParseIP(*addr)
+	if ip != nil {
+		listenAddr = fmt.Sprintf("%s:%v", ip.String(), *port)
+	} else {
+		if govalidator.IsDNSName(*addr) {
+			listenAddr = fmt.Sprintf("%s:%v", *addr, *port)
+		} else {
+			log.Fatalln("Invalid ip address")
+		}
+	}
+
+	if !govalidator.IsDNSName(*domain) {
+		log.Fatalln("Invalid domain address")
+	}
+
+	pool = cache.New(time.Duration(*exp)*time.Hour, time.Duration(*cleanup)*time.Hour)
+	t := template.Must(template.ParseFiles("templates/response.html"))
 	r := mux.NewRouter()
 
-	r.HandleFunc("/", cfg.index).Methods("GET")
+	// Index
-	r.HandleFunc("/", cfg.shortner).Methods("POST")
+	r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
-	r.HandleFunc("/{key}", cfg.redirect).Methods("GET")
+		t.Execute(w, body{
-	r.HandleFunc("/v1/dumpToFile", cfg.itemsDumpToFile).Methods("GET")
+			HasForm: true,
-	r.HandleFunc("/v1/fromFile", cfg.itemsFromFile).Methods("GET")
+			Line1:   "Welcome to Short, the simple URL shortener,",
-	r.HandleFunc("/v1/count", cfg.itemsCount).Methods("GET")
+			Line2:   "Type an URL below to shorten it",
-	r.HandleFunc("/v1/dump", cfg.itemsDump).Methods("GET")
+		})
-	r.HandleFunc("/v1/fromPost", cfg.itemsFromPost).Methods("POST")
+	}).Methods("GET")
 
-	log.Printf("Domain: %s, URL Proto: %s, Listen Address: %s\n", cfg.domain, cfg.proto, cfg.listenAddr)
+	// URL Shortener
-	log.Fatal(http.ListenAndServe(cfg.listenAddr, handlers.CombinedLoggingHandler(os.Stdout, r)))
+	r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		suf, err := shortener(r.FormValue("url"), *urlSize)
+		if err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			t.Execute(w, body{
+				FullHeader: true,
+				IsGhost:    true,
+				HasForm:    true,
+				H1:         "400",
+				H3:         err.Error(),
+				Line1:      "Boo, looks like this ghost stole this page!",
+				Line2:      "But you can type an URL below to shorten it",
+			})
+			return
+		}
+		ru, _ := url.Parse(fmt.Sprintf("%s://%s:%v/%s%s", *proto, *domain, *port, *path, suf))
+		t.Execute(w, body{
+			IsLink: true,
+			Line1:  ru.String(),
+		})
+	}).Methods("POST")
+
+	// URL Redirect
+	r.HandleFunc("/{key}", func(w http.ResponseWriter, r *http.Request) {
+		vals := mux.Vars(r)
+		key := vals["key"]
+		if *path != "" {
+			key = strings.Replace(key, *path, "", 1)
+		}
+		u, err := redirect(key)
+		if err != nil {
+			w.WriteHeader(http.StatusNotFound)
+			t.Execute(w, body{
+				FullHeader: true,
+				IsGhost:    true,
+				HasForm:    true,
+				H1:         "404",
+				H3:         err.Error(),
+				Line1:      "Boo, looks like this ghost stole this page!",
+				Line2:      "But you can type an URL below to shorten it",
+			})
+			return
+		}
+		http.Redirect(w, r, u, http.StatusFound)
+	}).Methods("GET")
+
+	// Dump DB to file
+	r.HandleFunc("/v1/toFile", func(w http.ResponseWriter, r *http.Request) {
+		i, err := dumpDbTOFile(*dumpFile)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			t.Execute(w, internalError("Failed to dump kv DB to file", err))
+			return
+		}
+		t.Execute(w, body{Line1: fmt.Sprintf("Exported %v items to %v", i, dumpFile)})
+	}).Methods("GET")
+
+	// Read DB from file
+	r.HandleFunc("/v1/fromFile", func(w http.ResponseWriter, r *http.Request) {
+		i, err := loadFromFile(*dumpFile, *exp, *cleanup)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			t.Execute(w, internalError("Error loading DB from file", err))
+			return
+		}
+		t.Execute(w, body{Line1: fmt.Sprintf("Imported %v items to the DB", i)})
+	}).Methods("GET")
+
+	// Count items on DB
+	r.HandleFunc("/v1/count", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintf(w, "%v", pool.ItemCount())
+	}).Methods("GET")
+
+	r.HandleFunc("/v1/dump", func(w http.ResponseWriter, r *http.Request) {
+		dumpObj, err := json.Marshal(pool.Items())
+		if err != nil {
+			t.Execute(w, internalError("Unable to dump key value db: ", err))
+			return
+		}
+		fmt.Fprintf(w, "%s", dumpObj)
+	}).Methods("GET")
+
+	// Loads DB from json POST
+	r.HandleFunc("/v1/fromPost", func(w http.ResponseWriter, r *http.Request) {
+		b, err := ioutil.ReadAll(r.Body)
+		if err != nil {
+			t.Execute(w, internalError("Unable to dump key value db: ", err))
+			return
+		}
+		i, err := loadFromJSON(b, *exp, *cleanup)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			t.Execute(w, internalError("Error loading DB", err))
+			return
+		}
+		t.Execute(w, body{Line1: fmt.Sprintf("Imported %v items to the DB", i)})
+	}).Methods("POST")
+
+	log.Printf("Domain: %s, URL Proto: %s, Listen Address: %s\n", *domain, *proto, listenAddr)
+	log.Fatal(http.ListenAndServe(listenAddr, handlers.CombinedLoggingHandler(os.Stdout, r)))
 }