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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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use arrow::{datatypes::SchemaRef, record_batch::RecordBatch};
use datafusion_common::Result;
use futures::Stream;
use std::pin::Pin;

/// Trait for types that stream [arrow::record_batch::RecordBatch]
pub trait RecordBatchStream: Stream<Item = Result<RecordBatch>> {
    /// Returns the schema of this `RecordBatchStream`.
    ///
    /// Implementation of this trait should guarantee that all `RecordBatch`'s returned by this
    /// stream should have the same schema as returned from this method.
    fn schema(&self) -> SchemaRef;
}

/// Trait for a [`Stream`](futures::stream::Stream) of [`RecordBatch`]es
pub type SendableRecordBatchStream = Pin<Box<dyn RecordBatchStream + Send>>;