Crate tokio_rusqlite
source · [−]Expand description
Asynchronous handle for rusqlite library.
Guide
This library provides Connection
struct. Connection
struct is a handle
to call functions in background thread and can be cloned cheaply.
Connection::call
method calls provided function in the background thread
and returns its result asynchronously.
Design
A thread is spawned for each opened connection handle. When call
method
is called: provided function is boxed, sent to the thread through mpsc
channel and executed. Return value is then sent by oneshot channel from
the thread and then returned from function.
Example
use rusqlite::{params, Result};
use tokio_rusqlite::Connection;
#[derive(Debug)]
struct Person {
id: i32,
name: String,
data: Option<Vec<u8>>,
}
#[tokio::main]
async fn main() -> Result<()> {
let conn = Connection::open_in_memory().await?;
let people = conn
.call(|conn| {
conn.execute(
"CREATE TABLE person (
id INTEGER PRIMARY KEY,
name TEXT NOT NULL,
data BLOB
)",
[],
)?;
let steven = Person {
id: 1,
name: "Steven".to_string(),
data: None,
};
conn.execute(
"INSERT INTO person (name, data) VALUES (?1, ?2)",
params![steven.name, steven.data],
)?;
let mut stmt = conn.prepare("SELECT id, name, data FROM person")?;
let people = stmt
.query_map([], |row| {
Ok(Person {
id: row.get(0)?,
name: row.get(1)?,
data: row.get(2)?,
})
})?
.collect::<Result<Vec<Person>, rusqlite::Error>>()?;
Ok::<_, rusqlite::Error>(people)
})
.await?;
for person in people {
println!("Found person {:?}", person);
}
Ok(())
}
Structs
A handle to call functions in background thread.