tmp2

Signed-off-by: junxiang Mu <1948535941@qq.com>

s3select/api/src/query/scheduler.rs

@@ -0,0 +1,32 @@
+use std::sync::Arc;
+
+use async_trait::async_trait;
+use datafusion::common::Result;
+use datafusion::execution::context::TaskContext;
+use datafusion::physical_plan::{ExecutionPlan, SendableRecordBatchStream};
+
+pub type SchedulerRef = Arc<dyn Scheduler + Send + Sync>;
+
+#[async_trait]
+pub trait Scheduler {
+    /// Schedule the provided [`ExecutionPlan`] on this [`Scheduler`].
+    ///
+    /// Returns a [`ExecutionResults`] that can be used to receive results as they are produced,
+    /// as a [`futures::Stream`] of [`RecordBatch`]
+    async fn schedule(&self, plan: Arc<dyn ExecutionPlan>, context: Arc<TaskContext>) -> Result<ExecutionResults>;
+}
+
+pub struct ExecutionResults {
+    stream: SendableRecordBatchStream,
+}
+
+impl ExecutionResults {
+    pub fn new(stream: SendableRecordBatchStream) -> Self {
+        Self { stream }
+    }
+
+    /// Returns a [`SendableRecordBatchStream`] of this execution
+    pub fn stream(self) -> SendableRecordBatchStream {
+        self.stream
+    }
+}