mirror of https://github.com/jackc/pgx.git
75 lines
1.4 KiB
Go
75 lines
1.4 KiB
Go
package main
|
|
|
|
import (
|
|
"bufio"
|
|
"context"
|
|
"fmt"
|
|
"os"
|
|
|
|
"github.com/jackc/pgx"
|
|
)
|
|
|
|
var pool *pgx.ConnPool
|
|
|
|
func main() {
|
|
config, err := pgx.ParseEnvLibpq()
|
|
if err != nil {
|
|
fmt.Fprintln(os.Stderr, "Unable to parse environment:", err)
|
|
os.Exit(1)
|
|
}
|
|
|
|
pool, err = pgx.NewConnPool(pgx.ConnPoolConfig{ConnConfig: config})
|
|
if err != nil {
|
|
fmt.Fprintln(os.Stderr, "Unable to connect to database:", err)
|
|
os.Exit(1)
|
|
}
|
|
|
|
go listen()
|
|
|
|
fmt.Println(`Type a message and press enter.
|
|
|
|
This message should appear in any other chat instances connected to the same
|
|
database.
|
|
|
|
Type "exit" to quit.`)
|
|
|
|
scanner := bufio.NewScanner(os.Stdin)
|
|
for scanner.Scan() {
|
|
msg := scanner.Text()
|
|
if msg == "exit" {
|
|
os.Exit(0)
|
|
}
|
|
|
|
_, err = pool.Exec("select pg_notify('chat', $1)", msg)
|
|
if err != nil {
|
|
fmt.Fprintln(os.Stderr, "Error sending notification:", err)
|
|
os.Exit(1)
|
|
}
|
|
}
|
|
if err := scanner.Err(); err != nil {
|
|
fmt.Fprintln(os.Stderr, "Error scanning from stdin:", err)
|
|
os.Exit(1)
|
|
}
|
|
}
|
|
|
|
func listen() {
|
|
conn, err := pool.Acquire()
|
|
if err != nil {
|
|
fmt.Fprintln(os.Stderr, "Error acquiring connection:", err)
|
|
os.Exit(1)
|
|
}
|
|
defer pool.Release(conn)
|
|
|
|
conn.Listen("chat")
|
|
|
|
for {
|
|
notification, err := conn.WaitForNotification(context.Background())
|
|
if err != nil {
|
|
fmt.Fprintln(os.Stderr, "Error waiting for notification:", err)
|
|
os.Exit(1)
|
|
}
|
|
|
|
fmt.Println("PID:", notification.PID, "Channel:", notification.Channel, "Payload:", notification.Payload)
|
|
}
|
|
}
|