opendal_core/services/memory/
backend.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
18use std::fmt::Debug;
19use std::sync::Arc;
20
21use super::MEMORY_SCHEME;
22use super::config::MemoryConfig;
23use super::core::*;
24use super::deleter::MemoryDeleter;
25use super::lister::MemoryLister;
26use super::writer::MemoryWriter;
27use crate::raw::oio;
28use crate::raw::*;
29use crate::*;
30
31/// In memory service support. (BTreeMap Based)
32#[doc = include_str!("docs.md")]
33#[derive(Debug, Default)]
34pub struct MemoryBuilder {
35    pub(super) config: MemoryConfig,
36}
37
38impl MemoryBuilder {
39    /// Set the root for BTreeMap.
40    pub fn root(mut self, path: &str) -> Self {
41        self.config.root = Some(path.into());
42        self
43    }
44}
45
46impl Builder for MemoryBuilder {
47    type Config = MemoryConfig;
48
49    fn build(self) -> Result<impl Access> {
50        let root = normalize_root(self.config.root.as_deref().unwrap_or("/"));
51
52        let core = MemoryCore::new();
53        Ok(MemoryBackend::new(core).with_normalized_root(root))
54    }
55}
56
57/// MemoryBackend implements Access trait directly
58#[derive(Debug, Clone)]
59pub struct MemoryBackend {
60    core: Arc<MemoryCore>,
61    root: String,
62    info: Arc<AccessorInfo>,
63}
64
65impl MemoryBackend {
66    fn new(core: MemoryCore) -> Self {
67        let info = AccessorInfo::default();
68        info.set_scheme(MEMORY_SCHEME);
69        info.set_name(&format!("{:p}", Arc::as_ptr(&core.data)));
70        info.set_root("/");
71        info.set_native_capability(Capability {
72            read: true,
73            write: true,
74            write_can_empty: true,
75            write_with_cache_control: true,
76            write_with_content_type: true,
77            write_with_content_disposition: true,
78            write_with_content_encoding: true,
79            write_with_if_not_exists: true,
80            delete: true,
81            stat: true,
82            list: true,
83            list_with_recursive: true,
84            shared: false,
85            ..Default::default()
86        });
87
88        Self {
89            core: Arc::new(core),
90            root: "/".to_string(),
91            info: Arc::new(info),
92        }
93    }
94
95    fn with_normalized_root(mut self, root: String) -> Self {
96        self.info.set_root(&root);
97        self.root = root;
98        self
99    }
100}
101
102impl Access for MemoryBackend {
103    type Reader = Buffer;
104    type Writer = MemoryWriter;
105    type Lister = oio::HierarchyLister<MemoryLister>;
106    type Deleter = oio::OneShotDeleter<MemoryDeleter>;
107    type Copier = ();
108
109    fn info(&self) -> Arc<AccessorInfo> {
110        self.info.clone()
111    }
112
113    async fn stat(&self, path: &str, _: OpStat) -> Result<RpStat> {
114        let p = build_abs_path(&self.root, path);
115
116        if p == build_abs_path(&self.root, "") {
117            Ok(RpStat::new(Metadata::new(EntryMode::DIR)))
118        } else {
119            match self.core.get(&p)? {
120                Some(value) => Ok(RpStat::new(value.metadata)),
121                None => Err(Error::new(
122                    ErrorKind::NotFound,
123                    "memory doesn't have this path",
124                )),
125            }
126        }
127    }
128
129    async fn read(&self, path: &str, args: OpRead) -> Result<(RpRead, Self::Reader)> {
130        let p = build_abs_path(&self.root, path);
131
132        let value = match self.core.get(&p)? {
133            Some(value) => value,
134            None => {
135                return Err(Error::new(
136                    ErrorKind::NotFound,
137                    "memory doesn't have this path",
138                ));
139            }
140        };
141
142        let total_size = value.content.len() as u64;
143        let range = args.range();
144        let start = range.offset().min(total_size) as usize;
145        let end = match range.size() {
146            Some(size) => range.offset().saturating_add(size).min(total_size),
147            None => total_size,
148        } as usize;
149        let content = value.content.slice(start..end);
150        let metadata = Metadata::new(EntryMode::FILE).with_content_length(total_size);
151
152        Ok((RpRead::new(metadata), content))
153    }
154
155    async fn write(&self, path: &str, args: OpWrite) -> Result<(RpWrite, Self::Writer)> {
156        let p = build_abs_path(&self.root, path);
157        Ok((
158            RpWrite::new(),
159            MemoryWriter::new(self.core.clone(), p, args),
160        ))
161    }
162
163    async fn delete(&self) -> Result<(RpDelete, Self::Deleter)> {
164        Ok((
165            RpDelete::default(),
166            oio::OneShotDeleter::new(MemoryDeleter::new(self.core.clone(), self.root.clone())),
167        ))
168    }
169
170    async fn list(&self, path: &str, args: OpList) -> Result<(RpList, Self::Lister)> {
171        let p = build_abs_path(&self.root, path);
172        let keys = self.core.scan(&p)?;
173        let lister = MemoryLister::new(&self.root, keys);
174        let lister = oio::HierarchyLister::new(lister, path, args.recursive());
175
176        Ok((RpList::default(), lister))
177    }
178}
opendal_core/services/memory/backend.rs

opendal_core/services/memory/
backend.rs
