func createConnPool() (*pgx.ConnPool, error) {
var config pgx.ConnPoolConfig
var err error
config.ConnConfig, err = pgx.ParseEnvLibpq()
if err != nil {
return nil, err
}
if config.Host == "" {
config.Host = "localhost"
}
if config.User == "" {
config.User = os.Getenv("USER")
}
if config.Database == "" {
config.Database = "pgxdata"
}
config.TLSConfig = nil
config.UseFallbackTLS = false
config.MaxConnections = 10
return pgx.NewConnPool(config)
}
func initDatabase(dbHost string, dbUser string, dbPass string, dbName string, dbPort uint16, maxConnectionsInPool int) (*pgx.ConnPool, error) {
var successOrFailure string = "OK"
var config pgx.ConnPoolConfig
config.Host = dbHost
config.User = dbUser
config.Password = dbPass
config.Database = dbName
config.Port = dbPort
config.MaxConnections = maxConnectionsInPool
config.AfterConnect = func(conn *pgx.Conn) error {
worldSelectStmt = mustPrepare(conn, "worldSelectStmt", "SELECT id, randomNumber FROM World WHERE id = $1")
worldUpdateStmt = mustPrepare(conn, "worldUpdateStmt", "UPDATE World SET randomNumber = $1 WHERE id = $2")
fortuneSelectStmt = mustPrepare(conn, "fortuneSelectStmt", "SELECT id, message FROM Fortune")
// Disable synchronous commit for the current db connection
// as a performance optimization.
// See http://www.postgresql.org/docs/current/static/runtime-config-wal.html
// for details.
if _, err := conn.Exec("SET synchronous_commit TO OFF"); err != nil {
log.Fatalf("Error when disabling synchronous commit")
}
return nil
}
fmt.Println("--------------------------------------------------------------------------------------------")
connPool, err := pgx.NewConnPool(config)
if err != nil {
successOrFailure = "FAILED"
log.Println("Connecting to database ", dbName, " as user ", dbUser, " ", successOrFailure, ": \n ", err)
} else {
log.Println("Connecting to database ", dbName, " as user ", dbUser, ": ", successOrFailure)
log.Println("Fetching one record to test if db connection is valid...")
var w World
n := randomWorldNum()
if errPing := connPool.QueryRow("worldSelectStmt", n).Scan(&w.Id, &w.RandomNumber); errPing != nil {
log.Fatalf("Error scanning world row: %s", errPing)
}
log.Println("OK")
}
fmt.Println("--------------------------------------------------------------------------------------------")
return connPool, err
}
func extractConfig() pgx.ConnPoolConfig {
var config pgx.ConnPoolConfig
config.Host = os.Getenv("CHAT_DB_HOST")
if config.Host == "" {
config.Host = "localhost"
}
config.User = os.Getenv("CHAT_DB_USER")
if config.User == "" {
config.User = os.Getenv("USER")
}
config.Password = os.Getenv("CHAT_DB_PASSWORD")
config.Database = os.Getenv("CHAT_DB_DATABASE")
if config.Database == "" {
config.Database = "postgres"
}
return config
}
func initDatabase(dbHost string, dbUser string, dbPass string, dbName string, dbPort uint16, maxConnectionsInPool int) (*pgx.ConnPool, error) {
var successOrFailure string = "OK"
var config pgx.ConnPoolConfig
config.Host = dbHost
config.User = dbUser
config.Password = dbPass
config.Database = dbName
config.Port = dbPort
config.MaxConnections = maxConnectionsInPool
config.AfterConnect = func(eachConn *pgx.Conn) error {
worldSelectStmt = mustPrepare(eachConn, "worldSelectStmt", "SELECT id, randomNumber FROM World WHERE id = $1")
worldUpdateStmt = mustPrepare(eachConn, "worldUpdateStmt", "UPDATE World SET randomNumber = $1 WHERE id = $2")
fortuneSelectStmt = mustPrepare(eachConn, "fortuneSelectStmt", "SELECT id, message FROM Fortune")
return nil
}
fmt.Println("--------------------------------------------------------------------------------------------")
connPool, err := pgx.NewConnPool(config)
if err != nil {
successOrFailure = "FAILED"
log.Println("Connecting to database ", dbName, " as user ", dbUser, " ", successOrFailure, ": \n ", err)
} else {
log.Println("Connecting to database ", dbName, " as user ", dbUser, ": ", successOrFailure)
log.Println("Fetching one record to test if db connection is valid...")
var w World
n := randomWorldNum()
if errPing := connPool.QueryRow("worldSelectStmt", n).Scan(&w.Id, &w.RandomNumber); errPing != nil {
log.Fatalf("Error scanning world row: %s", errPing)
}
log.Println("OK")
}
fmt.Println("--------------------------------------------------------------------------------------------")
return connPool, err
}