# Simple mysql driver for WASI 

This crate offers:

*   MySql database driver in pure rust;
*   connection pool;
*   Compiles to WebAssembly and runs in the [WasmEdge Runtime](https://github.com/WasmEdge/WasmEdge#readme) as a lightweight alternative to Linux containers;
*   We do not yet support SSL / TLS connections to databases in the WASI driver

For more details and usage examples, please see the upstream [rust-mysql-simple](https://github.com/blackbeam/rust-mysql-simple) source and [this example](https://github.com/WasmEdge/wasmedge-db-examples/tree/main/mysql).

### Installation

Put the desired version of the crate into the `dependencies` section of your `Cargo.toml`:

```toml
[dependencies]
mysql_wasi = "23.0.1"
```

### Example

```rust
use mysql::*;
use mysql::prelude::*;

#[derive(Debug, PartialEq, Eq)]
struct Payment {
    customer_id: i32,
    amount: i32,
    account_name: Option<String>,
}


fn main() -> std::result::Result<(), Box<dyn std::error::Error>> {
    let url = "mysql://root:password@localhost:3307/db_name";
    # Opts::try_from(url)?;
    # let url = get_opts();
    let pool = Pool::new(url)?;

    let mut conn = pool.get_conn()?;

    // Let's create a table for payments.
    conn.query_drop(
        r"CREATE TEMPORARY TABLE payment (
            customer_id int not null,
            amount int not null,
            account_name text
        )")?;

    let payments = vec![
        Payment { customer_id: 1, amount: 2, account_name: None },
        Payment { customer_id: 3, amount: 4, account_name: Some("foo".into()) },
        Payment { customer_id: 5, amount: 6, account_name: None },
        Payment { customer_id: 7, amount: 8, account_name: None },
        Payment { customer_id: 9, amount: 10, account_name: Some("bar".into()) },
    ];

    // Now let's insert payments to the database
    conn.exec_batch(
        r"INSERT INTO payment (customer_id, amount, account_name)
          VALUES (:customer_id, :amount, :account_name)",
        payments.iter().map(|p| params! {
            "customer_id" => p.customer_id,
            "amount" => p.amount,
            "account_name" => &p.account_name,
        })
    )?;

    // Let's select payments from database. Type inference should do the trick here.
    let selected_payments = conn
        .query_map(
            "SELECT customer_id, amount, account_name from payment",
            |(customer_id, amount, account_name)| {
                Payment { customer_id, amount, account_name }
            },
        )?;

    // Let's make sure, that `payments` equals to `selected_payments`.
    // Mysql gives no guaranties on order of returned rows
    // without `ORDER BY`, so assume we are lucky.
    assert_eq!(payments, selected_payments);
    println!("Yay!");

    Ok(())
}
```

## License

Licensed under either of

* Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or https://www.apache.org/licenses/LICENSE-2.0)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or https://opensource.org/licenses/MIT)

at your option.

### Contribution

Unless you explicitly state otherwise, any contribution intentionally
submitted for inclusion in the work by you, as defined in the Apache-2.0
license, shall be dual licensed as above, without any additional terms or
conditions.