Struct FlightTableFactory

pub struct FlightTableFactory { /* private fields */ }

Available on crate feature flight only.

Generic Arrow Flight data source. Requires a FlightDriver that allows implementors to integrate any custom Flight RPC service by producing a FlightMetadata for some DDL.

Sample usage:

#[derive(Debug, Clone, Default)]
struct CustomFlightDriver {}

#[async_trait::async_trait]
impl FlightDriver for CustomFlightDriver {
    async fn metadata(
        &self,
        channel: Channel,
        opts: &HashMap<String, String>,
    ) -> arrow_flight::error::Result<FlightMetadata> {
        let mut client = FlightClient::new(channel);
        // for simplicity, we'll just assume the server expects a string command and no handshake
        let descriptor = FlightDescriptor::new_cmd(opts["flight.command"].clone());
        let flight_info = client.get_flight_info(descriptor).await?;
        FlightMetadata::try_from(flight_info)
    }
}

#[tokio::main]
async fn main() {
    let ctx = SessionContext::new();
    ctx.state_ref().write().table_factories_mut().insert(
        "CUSTOM_FLIGHT".into(),
        Arc::new(FlightTableFactory::new(Arc::new(
            CustomFlightDriver::default(),
        ))),
    );
    let _ = ctx.sql(
        r#"
        CREATE EXTERNAL TABLE custom_flight_table STORED AS CUSTOM_FLIGHT
        LOCATION 'https://custom.flight.rpc'
        OPTIONS ('flight.command' 'AI, show me the data!')
    "#,
    ); // no .await here, so we don't actually try to connect to the bogus URL
}

Implementations

impl FlightTableFactory

pub fn new(driver: Arc<dyn FlightDriver>) -> Self

Create a data source using the provided driver

pub async fn open_table( &self, entry_point: impl Into<String>, options: HashMap<String, String>, ) -> Result<FlightTable>

Convenient way to create a FlightTable programatically, as an alternative to DDL.

Trait Implementations

impl Clone for FlightTableFactory

fn clone(&self) -> FlightTableFactory

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FlightTableFactory

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl TableProviderFactory for FlightTableFactory

fn create<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, _state: &'life1 dyn Session, cmd: &'life2 CreateExternalTable, ) -> Pin<Box<dyn Future<Output = Result<Arc<dyn TableProvider>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Create a TableProvider with the given url