sqlx/README.md
2019-06-10 21:57:50 -07:00

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# Mason
_Asynchronous and expressive database client in pure Rust_
This is an experiment being worked on in stages. The first stage
will be a very low-level, generic database driver (hopefully) capable of basic execution of
simple queries.
## Usage
What follows is _experimental_ usage (for thinking on API design) that is not currently implemented.
```rust
#![feature(async_await)]
use mason::pg::Connection;
#[runtime::main]
async fn main() -> Result<(), failure::Error> {
// this will likely be something like eventually:
// mason::Connection::<Pg>::establish(...)
let mut conn = Connection::establish(ConnectOptions::new().user("postgres")).await?;
// or: Connection::establish("postgres://postgres@localhost/").await?;
// or: ConnectOptions::new().user("postgres").establish().await?;
// Execute a "simple" query. Can consist of N statements separated by semicolons.
// No results are returned.
conn.execute("CREATE TABLE IF NOT EXISTS users ( id UUID PRIMARY KEY, name TEXT NOT NULL );")
.await?;
// prepare() -> Statement
// - A `Statement` can be cached and re-bound later for improved performance
conn.prepare("SELECT id FROM users WHERE name ilike $1")
// bind() -> Cursor (named [Cursor] in mysql or sqlite but [Portal] in postgres)
.bind(&["bob"])
// execute() -> u64
// - execute may be used instead of fetch to ignore all results and only
// return the "affected" rows
// fetch() -> Stream<Item = Row>
.fetch()
.collect::<Vec<Row>>()
.await?;
// Close is not strictly needed but this makes sure any pending writes to the connection
// are flushed and gracefully closes the connection
conn.close().await?;
Ok(())
}
```
## Notes
* [`AsyncDrop`](https://internals.rust-lang.org/t/async-await-the-challenges-besides-syntax-cancellation/10287/13) - Many of the
envisoned APIs would greatly benefit from something like this. There are cases where an object _must_ be closed or it would
be a memory leak (in either the client or server). I intended to provide both an `async fn close()` and a sync Drop impl
that blocks the thread and shouts a warning.. but that is obviously not ideal.
## License
Licensed under either of
* Apache License, Version 2.0
([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
* MIT license
([LICENSE-MIT](LICENSE-MIT) or http://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.