@@ -39,14 +39,90 @@ pub struct DefaultTableSource {
3939}
4040
4141impl DefaultTableSource {
42- /// Create a new DefaultTableSource to wrap a TableProvider
43- pub fn new ( table_provider : Arc < dyn TableProvider > ) -> Self {
44- Self { table_provider }
42+ /// Wraps a [TableProvider] as a [TableSource], to be used in planning.
43+ ///
44+ /// # Example
45+ /// ```
46+ /// # use std::sync::Arc;
47+ /// # use std::any::Any;
48+ /// # use arrow::datatypes::{Schema, SchemaRef};
49+ /// # use datafusion_expr::{Expr, TableType, TableSource};
50+ /// # use datafusion_physical_plan::ExecutionPlan;
51+ /// # use datafusion_common::Result;
52+ /// # use datafusion_catalog::{TableProvider, default_table_source::DefaultTableSource};
53+ /// # use datafusion_session::Session;
54+ /// # use async_trait::async_trait;
55+ ///
56+ /// # #[derive(Debug, Eq, PartialEq)]
57+ /// # struct MyTableProvider {};
58+ ///
59+ /// # #[async_trait]
60+ /// # impl TableProvider for MyTableProvider {
61+ /// # fn as_any(&self) -> &dyn Any { self }
62+ /// # fn schema(&self) -> SchemaRef { Arc::new(Schema::empty()) }
63+ /// # fn table_type(&self) -> TableType { TableType::Base }
64+ /// # async fn scan(
65+ /// # &self,
66+ /// # _: &dyn Session,
67+ /// # _: Option<&Vec<usize>>,
68+ /// # _: &[Expr],
69+ /// # _: Option<usize>,
70+ /// # ) -> Result<Arc<dyn ExecutionPlan>> {
71+ /// # unimplemented!()
72+ /// # }
73+ /// # }
74+ ///
75+ /// let provider = Arc::new(MyTableProvider {});
76+ /// let table_source = DefaultTableSource::wrap(provider);
77+ /// ```
78+ pub fn wrap ( table_provider : Arc < dyn TableProvider > ) -> Arc < Self > {
79+ Arc :: new ( Self { table_provider } )
4580 }
4681
47- /// Attempt to downcast a TableSource to DefaultTableSource and access the
48- /// TableProvider. This will only work with a TableSource created by DataFusion.
49- pub fn unwrap_provider < T : TableProvider + ' static > (
82+ /// Attempt to downcast a `TableSource` to `DefaultTableSource` and access
83+ /// the [TableProvider]. This will only work with a [TableSource] created
84+ /// by [`DefaultTableSource::wrap`].
85+ ///
86+ /// # Example
87+ /// ```
88+ /// # use std::sync::Arc;
89+ /// # use std::any::Any;
90+ /// # use arrow::datatypes::{Schema, SchemaRef};
91+ /// # use datafusion_common::Result;
92+ /// # use datafusion_expr::{Expr, TableType, TableSource};
93+ /// # use datafusion_physical_plan::ExecutionPlan;
94+ /// # use datafusion_catalog::{TableProvider, default_table_source::DefaultTableSource};
95+ /// # use datafusion_session::Session;
96+ /// # use async_trait::async_trait;
97+ ///
98+ /// # #[derive(Debug, Eq, PartialEq)]
99+ /// # struct MyTableProvider {}
100+ ///
101+ /// # #[async_trait]
102+ /// # impl TableProvider for MyTableProvider {
103+ /// # fn as_any(&self) -> &dyn Any { self }
104+ /// # fn schema(&self) -> SchemaRef { Arc::new(Schema::empty()) }
105+ /// # fn table_type(&self) -> TableType { TableType::Base }
106+ /// # async fn scan(
107+ /// # &self,
108+ /// # _: &dyn Session,
109+ /// # _: Option<&Vec<usize>>,
110+ /// # _: &[Expr],
111+ /// # _: Option<usize>,
112+ /// # ) -> Result<Arc<dyn ExecutionPlan>> {
113+ /// # unimplemented!()
114+ /// # }
115+ /// # }
116+ ///
117+ /// # fn example() -> Result<()> {
118+ /// let provider = Arc::new(MyTableProvider {});
119+ /// let table_source: Arc<dyn TableSource> = DefaultTableSource::wrap(provider.clone());
120+ /// let unwrapped = DefaultTableSource::unwrap::<MyTableProvider>(&table_source)?;
121+ /// assert_eq!(provider.as_ref(), unwrapped);
122+ /// # Ok(())
123+ /// # }
124+ /// ```
125+ pub fn unwrap < T : TableProvider + ' static > (
50126 source : & Arc < dyn TableSource > ,
51127 ) -> datafusion_common:: Result < & T > {
52128 if let Some ( source) = source
@@ -106,14 +182,16 @@ impl TableSource for DefaultTableSource {
106182}
107183
108184/// Wrap a TableProvider as a TableSource.
185+ #[ deprecated( note = "use DefaultTableSource::wrap instead" ) ]
109186pub fn provider_as_source (
110187 table_provider : Arc < dyn TableProvider > ,
111188) -> Arc < dyn TableSource > {
112- Arc :: new ( DefaultTableSource :: new ( table_provider) )
189+ DefaultTableSource :: wrap ( table_provider)
113190}
114191
115192/// Attempt to downcast a TableSource to DefaultTableSource and access the
116193/// TableProvider. This will only work with a TableSource created by DataFusion.
194+ #[ deprecated( note = "use DefaultTableSource::unwrap instead" ) ]
117195pub fn source_as_provider (
118196 source : & Arc < dyn TableSource > ,
119197) -> datafusion_common:: Result < Arc < dyn TableProvider > > {
@@ -161,6 +239,6 @@ fn preserves_table_type() {
161239 }
162240 }
163241
164- let table_source = DefaultTableSource :: new ( Arc :: new ( TestTempTable ) ) ;
242+ let table_source = DefaultTableSource :: wrap ( Arc :: new ( TestTempTable ) ) ;
165243 assert_eq ! ( table_source. table_type( ) , TableType :: Temporary ) ;
166244}
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