datafusion_catalog/memory/
catalog.rs

1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements.  See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership.  The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License.  You may obtain a copy of the License at
8//
9//   http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied.  See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18//! [`MemoryCatalogProvider`], [`MemoryCatalogProviderList`]: In-memory
19//! implementations of [`CatalogProviderList`] and [`CatalogProvider`].
20
21use crate::{CatalogProvider, CatalogProviderList, SchemaProvider};
22use dashmap::DashMap;
23use datafusion_common::exec_err;
24use std::sync::Arc;
25
26/// Simple in-memory list of catalogs
27#[derive(Debug)]
28pub struct MemoryCatalogProviderList {
29    /// Collection of catalogs containing schemas and ultimately TableProviders
30    pub catalogs: DashMap<String, Arc<dyn CatalogProvider>>,
31}
32
33impl MemoryCatalogProviderList {
34    /// Instantiates a new `MemoryCatalogProviderList` with an empty collection of catalogs
35    pub fn new() -> Self {
36        Self {
37            catalogs: DashMap::new(),
38        }
39    }
40}
41
42impl Default for MemoryCatalogProviderList {
43    fn default() -> Self {
44        Self::new()
45    }
46}
47
48impl CatalogProviderList for MemoryCatalogProviderList {
49    fn register_catalog(
50        &self,
51        name: String,
52        catalog: Arc<dyn CatalogProvider>,
53    ) -> Option<Arc<dyn CatalogProvider>> {
54        self.catalogs.insert(name, catalog)
55    }
56
57    fn catalog_names(&self) -> Vec<String> {
58        self.catalogs.iter().map(|c| c.key().clone()).collect()
59    }
60
61    fn catalog(&self, name: &str) -> Option<Arc<dyn CatalogProvider>> {
62        self.catalogs.get(name).map(|c| Arc::clone(c.value()))
63    }
64}
65
66/// Simple in-memory implementation of a catalog.
67#[derive(Debug)]
68pub struct MemoryCatalogProvider {
69    schemas: DashMap<String, Arc<dyn SchemaProvider>>,
70}
71
72impl MemoryCatalogProvider {
73    /// Instantiates a new MemoryCatalogProvider with an empty collection of schemas.
74    pub fn new() -> Self {
75        Self {
76            schemas: DashMap::new(),
77        }
78    }
79}
80
81impl Default for MemoryCatalogProvider {
82    fn default() -> Self {
83        Self::new()
84    }
85}
86
87impl CatalogProvider for MemoryCatalogProvider {
88    fn schema_names(&self) -> Vec<String> {
89        self.schemas.iter().map(|s| s.key().clone()).collect()
90    }
91
92    fn schema(&self, name: &str) -> Option<Arc<dyn SchemaProvider>> {
93        self.schemas.get(name).map(|s| Arc::clone(s.value()))
94    }
95
96    fn register_schema(
97        &self,
98        name: &str,
99        schema: Arc<dyn SchemaProvider>,
100    ) -> datafusion_common::Result<Option<Arc<dyn SchemaProvider>>> {
101        Ok(self.schemas.insert(name.into(), schema))
102    }
103
104    fn deregister_schema(
105        &self,
106        name: &str,
107        cascade: bool,
108    ) -> datafusion_common::Result<Option<Arc<dyn SchemaProvider>>> {
109        if let Some(schema) = self.schema(name) {
110            let table_names = schema.table_names();
111            match (table_names.is_empty(), cascade) {
112                (true, _) | (false, true) => {
113                    let (_, removed) = self.schemas.remove(name).unwrap();
114                    Ok(Some(removed))
115                }
116                (false, false) => exec_err!(
117                    "Cannot drop schema {} because other tables depend on it: {}",
118                    name,
119                    itertools::join(table_names.iter(), ", ")
120                ),
121            }
122        } else {
123            Ok(None)
124        }
125    }
126}
datafusion_catalog/memory/catalog.rs

datafusion_catalog/memory/
catalog.rs
