TheMathWizard/db/db.go

138 lines
2.8 KiB
Go

package main
import (
"database/sql"
"fmt"
_ "github.com/go-sql-driver/mysql"
)
// Connect to MySQL database.
type Database struct {
connection *sql.DB
statement *sql.Stmt
}
func NewDatabase(config map[string]string, username string, password string) (*Database, error) {
dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s", username, password, config["host"], config["port"], config["dbname"])
db, err := sql.Open("mysql", dsn)
if err != nil {
return nil, err
}
return &Database{
connection: db,
}, nil
}
func (d *Database) Query(query string, params ...interface{}) (*Database, error) {
stmt, err := d.connection.Prepare(query)
if err != nil {
return nil, err
}
d.statement = stmt
_, err = stmt.Exec(params...)
if err != nil {
return nil, err
}
return d, nil
}
func (d *Database) Find() (map[string]interface{}, error) {
result := make(map[string]interface{})
err := d.statement.QueryRow().Scan(result)
if err != nil {
return nil, err
}
return result, nil
}
func (d *Database) FindOrFail() (map[string]interface{}, error) {
result, err := d.Find()
if err != nil {
return nil, err
}
if result == nil {
return nil, fmt.Errorf("Record not found")
}
return result, nil
}
func (d *Database) Get() ([]map[string]interface{}, error) {
rows, err := d.statement.Query()
if err != nil {
return nil, err
}
defer rows.Close()
columns, err := rows.Columns()
if err != nil {
return nil, err
}
result := make([]map[string]interface{}, 0)
values := make([]interface{}, len(columns))
valuePtrs := make([]interface{}, len(columns))
for rows.Next() {
for i := 0; i < len(columns); i++ {
valuePtrs[i] = &values[i]
}
err := rows.Scan(valuePtrs...)
if err != nil {
return nil, err
}
entry := make(map[string]interface{})
for i, col := range columns {
val := values[i]
b, ok := val.([]byte)
if ok {
entry[col] = string(b)
} else {
entry[col] = val
}
}
result = append(result, entry)
}
return result, nil
}
func (d *Database) Delete(params string) (*Database, error) {
_, err := d.Query("DELETE FROM user WHERE username = ?", params)
if err != nil {
return nil, err
}
return d, nil
}
func (d *Database) Update(params map[string]interface{}) (*Database, error) {
_, err := d.Query("UPDATE user SET level = ?, xp = ?, coins = ? WHERE username = ?", params["level"], params["xp"], params["coins"], params["username"])
if err != nil {
return nil, err
}
return d, nil
}
func (d *Database) GetPlayerStats(params string) (map[string]interface{}, error) {
result, err := d.Query("SELECT username, level, lesson_count, xp, coins FROM user WHERE username = ?", params).Get()
if err != nil {
return nil, err
}
if len(result) == 0 {
return nil, fmt.Errorf("Record not found")
}
return result[0], nil
}