dbquery test

main.go

package main

import (
	"bufio"
	"database/sql"
	"fmt"
	"os"

	_ "github.com/lib/pq" // postgres driver
)

func checkErr(err error) {
	if err != nil {
		fmt.Println(err)
		os.Exit(1)
	}
}

type op int

const (
	query op = iota
	ping
)

func readKeyboardInput() op {
	reader := bufio.NewReader(os.Stdin)
	for {
		fmt.Println("Press 'q' to do an SQL query")
		fmt.Println("Press 'p' to do a db ping")
		fmt.Println("Press 'e' to exit")
		input, _, err := reader.ReadRune()
		if err != nil {
			fmt.Println(err)
			continue
		}
		switch input {
		case 'q':
			return query
		case 'p':
			return ping
		case 'e':
			os.Exit(0)
		}
	}
}

func main() {
	var opcnt int

	if len(os.Args) != 2 {
		fmt.Printf("usage: %s <psql-dsn>\n", os.Args[0])
		os.Exit(1)
	}

	dsn := os.Args[1]
	db, err := sql.Open("postgres", dsn)
	checkErr(err)

	for {
		fmt.Printf("#%d\n", opcnt)
		op := readKeyboardInput()
		opcnt++

		switch op {
		case query:
			_, err = db.Exec("SELECT 'HELLO'")
			if err != nil {
				fmt.Println("ERR:" + err.Error())
			} else {
				fmt.Println("SQL query successful")
			}

		case ping:
			err := db.Ping()
			if err != nil {
				fmt.Println("ERR:" + err.Error())
			} else {
				fmt.Println("Ping successful")
			}
		}
	}
}