Example model engine without ORM

package model

import (
    "database/sql"
    "fmt"
)

var (
    db *sql.DB
)

// getEngine initializes the db client and returns it
func getEngine() (db *sql.DB, err error) {
    // TODO make this variables come from global config
    port := 3306
    user := "test"
    password := "test"
    host := "127.0.0.1"
    dbname := "test"

    // Define datasource with all the params
    dataSourceName := fmt.Sprintf("%s:%s@(%s:%d)/%s?parseTime=true", user,
        password, host, port, dbname)
    // Initialize sql object
    db, err = sql.Open("mysql", dataSourceName)
    if err != nil {
        return nil, err
    }
    return db, err
}

// SetEngine Sets the DB client
func SetEngine() (err error) {
    db, err = getEngine()
    if err != nil {
        return err
    }
    return nil
}

// NewEngine initializes the database engine of the service
func NewEngine() (err error) {
    err = SetEngine()
    if err != nil {
        return err
    }

    // TODO ping database, make sure to return error if fail.
    return nil
}