datafusion/substrait/src/lib.rs

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// distributed with this work for additional information
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// to you under the Apache License, Version 2.0 (the
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//   http://www.apache.org/licenses/LICENSE-2.0
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#![doc(
    html_logo_url = "https://raw.githubusercontent.com/apache/datafusion/19fe44cf2f30cbdd63d4a4f52c74055163c6cc38/docs/logos/standalone_logo/logo_original.svg",
    html_favicon_url = "https://raw.githubusercontent.com/apache/datafusion/19fe44cf2f30cbdd63d4a4f52c74055163c6cc38/docs/logos/standalone_logo/logo_original.svg"
)]
#![cfg_attr(docsrs, feature(doc_cfg))]
// Make sure fast / cheap clones on Arc are explicit:
// https://github.com/apache/datafusion/issues/11143
#![cfg_attr(not(test), deny(clippy::clone_on_ref_ptr))]

//! Serialize / Deserialize DataFusion Plans to [Substrait.io]
//!
//! This crate provides support for serializing and deserializing both DataFusion
//! [`LogicalPlan`] and [`ExecutionPlan`] to and from the generated types in
//! [substrait::proto] from the [substrait] crate.
//!
//! [Substrait.io] provides a cross-language serialization format for relational
//! algebra (e.g. query plans and expressions), based on protocol buffers.
//!
//! [Substrait.io]: https://substrait.io/
//!
//! [`LogicalPlan`]: datafusion::logical_expr::LogicalPlan
//! [`ExecutionPlan`]: datafusion::physical_plan::ExecutionPlan
//!
//! Potential uses of this crate:
//! * Use DataFusion to run Substrait plans created by other systems (e.g. Apache Calcite)
//! * Use DataFusion to create plans to run on other systems
//! * Pass query plans over FFI boundaries, such as from Python to Rust
//! * Pass query plans across node boundaries
//!
//! # See Also
//!
//! Substrait does not (yet) support the full range of plans and expressions
//! that DataFusion offers. See the [datafusion-proto]  crate for a DataFusion
//! specific format that does support of the full range.
//!
//! [datafusion-proto]: https://docs.rs/datafusion-proto/latest/datafusion_proto
//!
//! Note that generated types  such as [`substrait::proto::Plan`] and
//! [`substrait::proto::Rel`] can be serialized / deserialized to bytes, JSON and
//! other formats using [prost] and the rest of the Rust protobuf ecosystem.
//!
//! # Example: Serializing [`LogicalPlan`]s
//! ```
//! # use datafusion::prelude::*;
//! # use datafusion::error::Result;
//! # #[tokio::main(flavor = "current_thread")]
//! # async fn main() -> Result<()>{
//! # use std::sync::Arc;
//! # use datafusion::arrow::array::{Int32Array, RecordBatch};
//! # use datafusion_substrait::logical_plan;
//! // Create a plan that scans table 't'
//! let ctx = SessionContext::new();
//! let batch = RecordBatch::try_from_iter(vec![(
//!     "x",
//!     Arc::new(Int32Array::from(vec![42])) as _,
//! )])?;
//! ctx.register_batch("t", batch)?;
//! let df = ctx.sql("SELECT x from t").await?;
//! let plan = df.into_optimized_plan()?;
//!
//! // Convert the plan into a substrait (protobuf) Plan
//! let substrait_plan = logical_plan::producer::to_substrait_plan(&plan, &ctx.state())?;
//!
//! // Receive a substrait protobuf from somewhere, and turn it into a LogicalPlan
//! let logical_round_trip =
//!     logical_plan::consumer::from_substrait_plan(&ctx.state(), &substrait_plan)
//!         .await?;
//! let logical_round_trip = ctx.state().optimize(&logical_round_trip)?;
//! assert_eq!(format!("{:?}", plan), format!("{:?}", logical_round_trip));
//! # Ok(())
//! # }
//! ```
pub mod extensions;
pub mod logical_plan;
#[cfg(feature = "physical")]
pub mod physical_plan;
pub mod serializer;
pub mod variation_const;

// Re-export substrait crate
pub use substrait;