anmeldeportal_hochzeit/backend/go/src/server/main.go

package main

import (
	"database/sql"
	"fmt"
	_ "github.com/mattn/go-sqlite3"
	"log"
	"net/http"
	"strconv"
)

type Response struct {
	FirstName, Name   string
	Answer            string
	NumAdult, NumKids uint
	Vegi, Vegan       bool
	NumVegi, NumVegan uint
	Allerien          bool
	Allergene         string
	Accumodation      bool
	NumRooms          uint
	Arrival           string
	Musik             string
	Email             string
	Permission        bool
	Covid19           string
}

func newRespose(db *sql.DB, row *Response) error {
	sqlStmt := fmt.Sprintf(`INSERT INTO response
                                  (fName, lName, answer, numAdult, numKids, vegi, numVegi, vegan, numVegan, allergiger, allergene, accommodation, numRooms, arrival, musik, email, permission, covid19)
                                  VALUES
                                  (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);`)

	tx, err := db.Begin()
	if err != nil {
		return err
	}

	stmt, err := tx.Prepare(sqlStmt)
	defer tx.Commit()
	if err != nil {
		return err
	}
	defer stmt.Close()

	log.Printf("Add new response: %s", row)
	_, err = stmt.Exec(
		row.FirstName, row.Name,
		row.Answer,
		row.NumAdult, row.NumKids,
		row.Vegi, row.NumVegi,
		row.Vegan, row.NumVegan,
		row.Allerien, row.Allergene,
		row.Accumodation, row.NumRooms,
		row.Arrival,
		row.Musik,
		row.Email, row.Permission,
		row.Covid19,
	)
	if err != nil {
		return err
	}

	return nil
}

func initDB(dbS string) (*sql.DB, error) {
	db, err := sql.Open("sqlite3", dbS)
	if err != nil {
		return nil, err
	}

	sqlStmt := fmt.Sprintf(`CREATE TABLE IF NOT EXISTS response
                                  (id INTEGER NOT NULL PRIMARY KEY,
                                   fName TEXT NOT NULL, lName TEXT NOT NULL,
                                   answer TEXT NOT NULL,
                                   numAdult INTEGER NOT NULL, numKids INTEGER NOT NULL,
                                   vegi BOOLEAN, numVegi INTEGER,
                                   vegan BOOLEAN, numVegan INTEGER,
                                   allergiger BOOLEAN, allergene TEXT,
                                   accommodation BOOLEAN, numRooms INTEGER,
                                   arrival TEXT,
                                   musik TEXT,
                                   email TEXT, permission BOOLEAN,
                                   covid19 TEXT,
                                   created DATETIME DEFAULT CURRENT_TIMESTAMP);`)
	_, err = db.Exec(sqlStmt)
	if err != nil {
		return db, err
	}

	log.Printf("DB %s is up and running", dbS)
	return db, nil
}

func main() {
	// init database
	db, err := initDB("data/response.sqlite")
	if err != nil {
		if db != nil {
			db.Close()
		}
		log.Panic(err)
	}
	defer db.Close()

	// init http server with two routes for onepage website and endpoint for sending the response
	// http.Handle("/", httpLogHandler(http.FileServer(http.Dir("../../../../frontend"))))
	http.Handle("/", httpLogHandler(http.FileServer(http.Dir("./frontend"))))
	http.HandleFunc("/response", func(w http.ResponseWriter, r *http.Request) {
		processAnmeldung(w, r, db)
	})

	http.ListenAndServe(":8080", nil)
}

func parseBool(s string) bool {
	return s == "on"
}

func parseUInt(s string) uint {
	u64, err := strconv.ParseUint(s, 10, 32)
	if err != nil {
		return 0
	}
	return uint(u64)
}

func httpLogHandler(h http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		log.Printf("Webseiten Aufruf: '%v:%v' %v", r.Method, r.URL, r.Header)
		h.ServeHTTP(w, r)
	})
}

func processAnmeldung(w http.ResponseWriter, r *http.Request, db *sql.DB) {
	log.Printf("Process Endpoint Aufruf: '%v:%v' %v", r.Method, r.URL, r.Header)

	if r.Method != http.MethodPost {
		http.Redirect(w, r, "/", http.StatusSeeOther)
		return
	}

	// Call ParseForm() to parse the raw query and update r.PostForm and r.Form.
	if err := r.ParseForm(); err != nil {
		fmt.Fprintf(w, "ParseForm() err: %v", err)
		w.WriteHeader(http.StatusInternalServerError)
		return
	}
	log.Printf("Post from website: %v", r.PostForm)

	response := Response{
		FirstName:    r.FormValue("firstname"),
		Name:         r.FormValue("name"),
		Answer:       r.FormValue("rueckmeldung"),
		NumAdult:     parseUInt(r.FormValue("numAdult")),
		NumKids:      parseUInt(r.FormValue("numKids")),
		Vegi:         parseBool(r.FormValue("vegi")),
		Vegan:        parseBool(r.FormValue("vegan")),
		NumVegi:      parseUInt(r.FormValue("numVegi")),
		NumVegan:     parseUInt(r.FormValue("numVegan")),
		Allergene:    r.FormValue("allagene"),
		Allerien:     parseBool(r.FormValue("allergiger")),
		Accumodation: parseBool(r.FormValue("unterkunft")),
		Arrival:      r.FormValue("arrival"),
		NumRooms:     parseUInt(r.FormValue("numUnterkunft")),
		Musik:        r.FormValue("musik"),
		Email:        r.FormValue("email"),
		Permission:   parseBool(r.FormValue("weitergabe")),
		Covid19:      r.FormValue("covid19"),
	}
	log.Printf("Form values parsed: %v", response)

	err := newRespose(db, &response)
	if err != nil {
		log.Print("Fehler beim einfügen in die DB: %v", err)
		w.WriteHeader(http.StatusInternalServerError)
		return
	}

	//return success
	w.WriteHeader(http.StatusCreated)
}