adrielc/helios-alpha/golem-add-mysql-rust

use golem_rust::bindings::golem::rdbms::mysql::{
    DbConnection,
    DbValue,
};

let conn = DbConnection::open("mysql://user:password@localhost:3306/app")
    .map_err(|err| format!("{err:?}"))?;

let result = conn
    .query(
        "SELECT ?",
        vec![DbValue::Varchar("hello".to_string())],
    )
    .map_err(|err| format!("{err:?}"))?;
 
let row = result.rows.first().ok_or("query returned no rows")?;
let value = row.values.first().ok_or("query returned no columns")?;
 
let message = match value {
    DbValue::Varchar(value)
    | DbValue::Text(value)
    | DbValue::Tinytext(value)
    | DbValue::Mediumtext(value)
    | DbValue::Longtext(value)
    | DbValue::Fixchar(value) => value.clone(),
    other => return Err(format!("unexpected MySQL value: {other:?}")),
};

let affected = conn
    .execute(
        "INSERT INTO notes (id, body) VALUES (?, ?)",
        vec![DbValue::Int(1), DbValue::Varchar("hello".to_string())],
    )
    .map_err(|err| format!("{err:?}"))?;

let tx = conn.begin_transaction().map_err(|err| format!("{err:?}"))?;
 
tx.execute(
    "UPDATE notes SET body = ? WHERE id = ?",
    vec![DbValue::Varchar("updated".to_string()), DbValue::Int(1)],
)
.map_err(|err| format!("{err:?}"))?;
 
tx.commit().map_err(|err| format!("{err:?}"))?;