Initial commit

main.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"os"
+
+	"github.com/iris-contrib/middleware/logger"
+	"github.com/kataras/iris"
+)
+
+func main() {
+	shortner := NewShortner()
+	defer shortner.Close()
+
+	routes := Routes{Shortner: shortner}
+
+	iris.Use(logger.New(iris.Logger))
+	iris.Get("/set/:key/:value", routes.Set)
+	iris.Get("/get/:key", routes.Get)
+	iris.Get("/shorten/:url", routes.Shorten)
+	iris.Get("/lookup/:uid", routes.Lookup)
+	iris.Get("/", routes.Root)
+
+	port := os.Getenv("PORT")
+	if port == "" {
+		port = "8080"
+	}
+
+	iris.Listen(":" + port)
+}

routes.go

@@ -0,0 +1,54 @@
+package main
+
+import "github.com/kataras/iris"
+
+// Routes handles HTTP requests from iris.
+type Routes struct {
+	Shortner *Shortner
+}
+
+// Root returns the root.
+func (r *Routes) Root(c *iris.Context) {
+	c.Write("hello world")
+}
+
+// Get fetches a value for a given key.
+func (r *Routes) Get(c *iris.Context) {
+	key := c.Param("key")
+	value := r.Shortner.Get([]byte(key))
+	c.Write(string(value))
+}
+
+// Set writes a given value to the specified key.
+func (r *Routes) Set(c *iris.Context) {
+	key := []byte(c.Param("key"))
+	value := []byte(c.Param("value"))
+	err := r.Shortner.Set(key, value)
+
+	if err == nil {
+		c.Write("OK")
+	} else {
+		c.Log("ERROR: ", err.Error(), "\n")
+		c.Write("Oops >_<")
+	}
+}
+
+// Shorten attempts to shorten a URL to a UID
+func (r *Routes) Shorten(c *iris.Context) {
+	url := []byte(c.Param("url"))
+	uid, err := r.Shortner.Shorten(url)
+
+	if err == nil {
+		c.Write("Shortened: %s", uid)
+	} else {
+		c.Log("ERROR: ", err.Error(), "\n")
+		c.Write("Oops >_<")
+	}
+}
+
+// Lookup attempts to fetch previously shortened URLs based on UID
+func (r *Routes) Lookup(c *iris.Context) {
+	uid := []byte(c.Param("uid"))
+	url := r.Shortner.Lookup(uid)
+	c.Write("URL: %s", url)
+}

shortner.go

@@ -0,0 +1,100 @@
+package main
+
+import (
+	"log"
+	"strconv"
+
+	"github.com/jbenet/go-base58"
+	"github.com/syndtr/goleveldb/leveldb"
+)
+
+// NewShortner returns a new Shortner.
+func NewShortner() *Shortner {
+	db, err := leveldb.OpenFile("shortner.db", nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	return &Shortner{
+		Db:        db,
+		KeyPrefix: []byte("url:"),
+	}
+}
+
+// Shortner shortens URLs.
+type Shortner struct {
+	Db        *leveldb.DB
+	KeyPrefix []byte
+}
+
+// Close calls Close() on the goleveldb.
+func (s *Shortner) Close() {
+	err := s.Db.Close()
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+// Get reads from the database.
+func (s *Shortner) Get(key []byte) []byte {
+	value, _ := s.Db.Get(key, nil)
+	return value
+}
+
+// Set writes to the database.
+func (s *Shortner) Set(key []byte, value []byte) error {
+	return s.Db.Put(key, value, nil)
+}
+
+// Shorten shortens given URL
+func (s *Shortner) Shorten(url []byte) ([]byte, error) {
+	uid, err := s.newUID()
+	if err != nil {
+		return []byte{}, err
+	}
+
+	key := s.makeKey(uid)
+	err = s.Set(key, url)
+	if err != nil {
+		return []byte{}, err
+	}
+
+	return uid, nil
+}
+
+// Lookup attempts to fetch the value for given UID
+func (s *Shortner) Lookup(uid []byte) []byte {
+	return s.Get(s.makeKey(uid))
+}
+
+func (s *Shortner) makeKey(uid []byte) []byte {
+	return append(s.KeyPrefix, uid...)
+}
+
+func (s *Shortner) newUID() ([]byte, error) {
+	key := []byte("index")
+
+	tx, err := s.Db.OpenTransaction()
+	defer tx.Commit()
+
+	if err != nil {
+		return []byte{}, err
+	}
+
+	index, _ := tx.Get(key, nil)
+	if index == nil {
+		index = []byte("1")
+	}
+
+	num, _ := strconv.Atoi(string(index))
+	num++
+	index = []byte(strconv.Itoa(num))
+
+	err = tx.Put(key, index, nil)
+	if err != nil {
+		return []byte{}, err
+	}
+
+	uid := base58.Encode(index)
+	return []byte(uid), nil
+}