lib.rs

// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright the Vortex contributors

//! Connectors to enable [DataFusion](https://docs.rs/datafusion/latest/datafusion/) to read [`Vortex`](https://docs.rs/crate/vortex/latest) data.
#![deny(missing_docs)]
use std::fmt::Debug;

use datafusion_common::stats::Precision as DFPrecision;
use vortex::expr::stats::Precision;

mod convert;
mod persistent;
pub mod vendor;

pub use convert::exprs::DefaultExpressionConvertor;
pub use convert::exprs::ExpressionConvertor;
pub use persistent::*;

/// Extension trait to convert our [`Precision`](vortex::stats::Precision) to Datafusion's [`Precision`](datafusion_common::stats::Precision)
trait PrecisionExt<T>
where
    T: Debug + Clone + PartialEq + Eq + PartialOrd,
{
    /// Convert `Precision` to the datafusion equivalent.
    fn to_df(self) -> DFPrecision<T>;
}

impl<T> PrecisionExt<T> for Precision<T>
where
    T: Debug + Clone + PartialEq + Eq + PartialOrd,
{
    fn to_df(self) -> DFPrecision<T> {
        match self {
            Precision::Exact(v) => DFPrecision::Exact(v),
            Precision::Inexact(v) => DFPrecision::Inexact(v),
        }
    }
}

impl<T> PrecisionExt<T> for Option<Precision<T>>
where
    T: Debug + Clone + PartialEq + Eq + PartialOrd,
{
    fn to_df(self) -> DFPrecision<T> {
        match self {
            Some(v) => v.to_df(),
            None => DFPrecision::Absent,
        }
    }
}

#[cfg(test)]
mod common_tests {
    use std::sync::Arc;
    use std::sync::LazyLock;

    use datafusion::arrow::array::RecordBatch;
    use datafusion::datasource::provider::DefaultTableFactory;
    use datafusion::execution::SessionStateBuilder;
    use datafusion::prelude::SessionContext;
    use datafusion_common::GetExt;
    use object_store::ObjectStore;
    use object_store::memory::InMemory;
    use url::Url;
    use vortex::VortexSessionDefault;
    use vortex::array::ArrayRef;
    use vortex::array::arrow::FromArrowArray;
    use vortex::file::WriteOptionsSessionExt;
    use vortex::io::ObjectStoreWriter;
    use vortex::io::VortexWrite;
    use vortex::session::VortexSession;

    use crate::VortexFormatFactory;
    use crate::VortexOptions;

    static VX_SESSION: LazyLock<VortexSession> = LazyLock::new(VortexSession::default);

    pub struct TestSessionContext {
        pub store: Arc<dyn ObjectStore>,
        pub session: SessionContext,
    }

    impl Default for TestSessionContext {
        fn default() -> Self {
            Self::new(false)
        }
    }

    impl TestSessionContext {
        /// Create a new test session context with the given projection pushdown setting.
        pub fn new(projection_pushdown: bool) -> Self {
            let store = Arc::new(InMemory::new());
            let opts = VortexOptions {
                projection_pushdown,
                ..Default::default()
            };
            let factory = Arc::new(VortexFormatFactory::new().with_options(opts));
            let mut session_state_builder = SessionStateBuilder::new()
                .with_default_features()
                .with_table_factory(
                    factory.get_ext().to_uppercase(),
                    Arc::new(DefaultTableFactory::new()),
                )
                .with_object_store(&Url::try_from("file://").unwrap(), store.clone());

            if let Some(file_formats) = session_state_builder.file_formats() {
                file_formats.push(factory as _);
            }

            let session: SessionContext =
                SessionContext::new_with_state(session_state_builder.build()).enable_url_table();

            Self { store, session }
        }

        /// Write arrow data into a vortex file.
        pub async fn write_arrow_batch<P>(&self, path: P, batch: &RecordBatch) -> anyhow::Result<()>
        where
            P: Into<object_store::path::Path>,
        {
            let array = ArrayRef::from_arrow(batch, false);
            let mut write = ObjectStoreWriter::new(self.store.clone(), &path.into()).await?;
            VX_SESSION
                .write_options()
                .write(&mut write, array.to_array_stream())
                .await?;
            write.shutdown().await?;

            Ok(())
        }
    }
}