refactor: Rewrite server in go

1 files changed, 142 insertions, 0 deletions

diff --git a/server/main.go b/server/main.go
new file mode 100644
index 0000000..4618e5b
--- /dev/null
+++ b/server/main.go
@@ -0,0 +1,142 @@
+package main
+
+import (
+	"database/sql"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"math/rand"
+	"net/http"
+	"strings"
+	"time"
+
+	_ "github.com/mattn/go-sqlite3"
+	"github.com/rs/cors"
+)
+
+var db *sql.DB
+var port int
+var dbFilePath string
+
+type Bin struct {
+	Content  string `json:"content"`
+	Language string `json:"language"`
+}
+
+const (
+	shortIDCharset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	shortIDLength  = 8
+)
+
+func main() {
+	flag.IntVar(&port, "port", 8080, "Port number for the server (default is 8080)")
+	flag.StringVar(&dbFilePath, "db", "./minibin.db", "Database file path")
+	flag.Parse()
+
+	setupServer()
+}
+
+func setupServer() {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/bin", postBin)
+	mux.HandleFunc("/bin/", getBin)
+	handler := cors.Default().Handler(mux)
+	serverAddr := fmt.Sprintf(":%d", port)
+	log.Printf("Server listening on port %d...\n", port)
+	initDatabase()
+	log.Fatal(http.ListenAndServe(serverAddr, handler))
+}
+
+func initDatabase() {
+	var err error
+	db, err = sql.Open("sqlite3", dbFilePath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = createTable()
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func postBin(w http.ResponseWriter, r *http.Request) {
+	handleRequestMethod(w, r, "POST", func() {
+		body, err := ioutil.ReadAll(r.Body)
+		if handleError(w, err, http.StatusInternalServerError) {
+			return
+		}
+		var bin Bin
+		err = json.Unmarshal(body, &bin)
+		if handleError(w, err, http.StatusBadRequest) {
+			return
+		}
+		id := generateShortID()
+		handleError(w, saveBin(id, bin), http.StatusInternalServerError)
+		respondWithJSON(w, http.StatusOK, map[string]string{"id": id, "content": bin.Content, "language": bin.Language})
+	})
+}
+
+func getBin(w http.ResponseWriter, r *http.Request) {
+	handleRequestMethod(w, r, "GET", func() {
+		id := strings.TrimPrefix(r.URL.Path, "/bin/")
+		bin, err := getBinById(id)
+		handleError(w, err, http.StatusInternalServerError)
+		respondWithJSON(w, http.StatusOK, bin)
+	})
+}
+
+func handleRequestMethod(w http.ResponseWriter, r *http.Request, expectedMethod string, handler func()) {
+	if r.Method != expectedMethod {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	handler()
+}
+
+func handleError(w http.ResponseWriter, err error, statusCode int) bool {
+	if err != nil {
+		http.Error(w, err.Error(), statusCode)
+		return true
+	}
+	return false
+}
+
+func respondWithJSON(w http.ResponseWriter, statusCode int, data interface{}) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(statusCode)
+	json.NewEncoder(w).Encode(data)
+}
+
+func createTable() error {
+	_, err := db.Exec(`
+	CREATE TABLE IF NOT EXISTS bins (
+		id TEXT PRIMARY KEY,
+		content TEXT,
+		language TEXT
+	)
+`)
+	return err
+}
+
+func getBinById(id string) (Bin, error) {
+	var bin Bin
+	err := db.QueryRow("SELECT content, language FROM bins WHERE id = ?", id).Scan(&bin.Content, &bin.Language)
+	return bin, err
+}
+
+func saveBin(id string, bin Bin) error {
+	_, err := db.Exec("INSERT INTO bins (id, content, language) VALUES (?, ?, ?)", id, bin.Content, bin.Language)
+	return err
+}
+
+func generateShortID() string {
+	rand.Seed(time.Now().UnixNano())
+	id := make([]byte, shortIDLength)
+	for i := range id {
+		id[i] = shortIDCharset[rand.Intn(len(shortIDCharset))]
+	}
+	return string(id)
+}