1 files changed, 58 insertions, 0 deletions
diff --git a/pkg/database/database.go b/pkg/database/database.go
new file mode 100644
index 0000000..c89a334
--- /dev/null
+++ b/pkg/database/database.go
@@ -0,0 +1,58 @@
+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(&currentVersion); 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
+}