dendrite/internal/sqlutil/sqlutil.go
2022-10-04 12:01:37 +01:00

68 lines
2.5 KiB
Go

package sqlutil
import (
"database/sql"
"fmt"
"regexp"
"github.com/matrix-org/dendrite/setup/config"
"github.com/sirupsen/logrus"
)
// Open opens a database specified by its database driver name and a driver-specific data source name,
// usually consisting of at least a database name and connection information. Includes tracing driver
// if DENDRITE_TRACE_SQL=1
func Open(dbProperties *config.DatabaseOptions, writer Writer) (*sql.DB, error) {
var err error
var driverName, dsn string
switch {
case dbProperties.ConnectionString.IsSQLite():
driverName = "sqlite3"
dsn, err = ParseFileURI(dbProperties.ConnectionString)
if err != nil {
return nil, fmt.Errorf("ParseFileURI: %w", err)
}
case dbProperties.ConnectionString.IsPostgres():
driverName = "postgres"
dsn = string(dbProperties.ConnectionString)
default:
return nil, fmt.Errorf("invalid database connection string %q", dbProperties.ConnectionString)
}
if tracingEnabled {
// install the wrapped driver
driverName += "-trace"
}
db, err := sql.Open(driverName, dsn)
if err != nil {
return nil, err
}
if driverName != "sqlite3" {
logger := logrus.WithFields(logrus.Fields{
"max_open_conns": dbProperties.MaxOpenConns(),
"max_idle_conns": dbProperties.MaxIdleConns(),
"conn_max_lifetime": dbProperties.ConnMaxLifetime(),
"data_source_name": regexp.MustCompile(`://[^@]*@`).ReplaceAllLiteralString(dsn, "://"),
})
logger.Debug("Setting DB connection limits")
db.SetMaxOpenConns(dbProperties.MaxOpenConns())
db.SetMaxIdleConns(dbProperties.MaxIdleConns())
db.SetConnMaxLifetime(dbProperties.ConnMaxLifetime())
if driverName == "postgres" {
// Perform a quick sanity check if possible that we aren't trying to use more database
// connections than PostgreSQL is willing to give us.
var max, reserved int
if err := db.QueryRow("SELECT setting::integer FROM pg_settings WHERE name='max_connections';").Scan(&max); err != nil {
return nil, fmt.Errorf("failed to find maximum connections: %w", err)
}
if err := db.QueryRow("SELECT setting::integer FROM pg_settings WHERE name='superuser_reserved_connections';").Scan(&reserved); err != nil {
return nil, fmt.Errorf("failed to find reserved connections: %w", err)
}
if configured, allowed := dbProperties.MaxOpenConns(), max-reserved; configured > allowed {
return nil, fmt.Errorf("the max_open_conns is greater than the %d non-superuser connections that PostgreSQL is configured to allow", allowed)
}
}
}
return db, nil
}