minibin/server/main.go

142 lines
3.2 KiB
Go

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)
}