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package database
import (
"database/sql"
"time"
_ "github.com/mattn/go-sqlite3"
)
// DBEnv is the struct that holds this package together
type DBEnv struct {
db *sql.DB
}
// InitDB initializes database access and the connection pool
func InitDB(dbType string, dsn string) (*DBEnv, error) {
db, err := sql.Open(dbType, dsn)
if err != nil {
return nil, newInitError(dsn, err)
}
db.SetMaxOpenConns(25)
db.SetMaxIdleConns(25)
db.SetConnMaxLifetime(5 * time.Minute)
if err := db.Ping(); err != nil {
_ = db.Close() // TODO think about handling this error case?
return nil, newInitError(dsn, err)
}
return &DBEnv{db: db}, nil
}
// Migrate performs the migrations of the database to the latest schema_version
func (env *DBEnv) Migrate() error {
var currentVersion int
if err := env.db.QueryRow(`SELECT version FROM schema_version`).Scan(¤tVersion); err != nil {
currentVersion = 0
}
for version := currentVersion; version < len(migrations); version++ {
newVersion := version + 1
tx, err := env.db.Begin()
if err != nil {
return newTransactionError("Could not begin transaction", err)
}
if err := migrations[version](tx); err != nil {
tx.Rollback()
return newMigrationError(newVersion, err)
}
if _, err := tx.Exec(`DELETE FROM schema_version; INSERT INTO schema_version (version) VALUES ($1)`, newVersion); err != nil {
tx.Rollback()
return newMigrationError(newVersion, err)
}
if err := tx.Commit(); err != nil {
return newTransactionError("Could not commit transaction", err)
}
}
return nil
}
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