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 Service> {
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 [`Service`] for the in-memory map.
58#[derive(Debug, Clone)]
59pub struct MemoryBackend {
60    core: Arc<MemoryCore>,
61    root: String,
62    info: ServiceInfo,
63    capability: Capability,
64}
65
66impl MemoryBackend {
67    fn new(core: MemoryCore) -> Self {
68        let capability = Capability {
69            read: true,
70            read_with_suffix: true,
71            write: true,
72            write_can_empty: true,
73            write_with_cache_control: true,
74            write_with_content_type: true,
75            write_with_content_disposition: true,
76            write_with_content_encoding: true,
77            write_with_if_not_exists: true,
78            delete: true,
79            stat: true,
80            list: true,
81            list_with_recursive: true,
82            ..Default::default()
83        };
84
85        Self {
86            info: ServiceInfo::new(MEMORY_SCHEME, "/", format!("{:p}", Arc::as_ptr(&core.data))),
87            core: Arc::new(core),
88            root: "/".to_string(),
89            capability,
90        }
91    }
92
93    fn with_normalized_root(mut self, root: String) -> Self {
94        self.info = ServiceInfo::new(MEMORY_SCHEME, root.clone(), self.info.name());
95        self.root = root;
96        self
97    }
98}
99
100impl Service for MemoryBackend {
101    type Reader = oio::StreamReader<MemoryReader>;
102    type Writer = MemoryWriter;
103    type Lister = oio::HierarchyLister<MemoryLister>;
104    type Deleter = oio::OneShotDeleter<MemoryDeleter>;
105    type Copier = ();
106
107    fn info(&self) -> ServiceInfo {
108        self.info.clone()
109    }
110
111    fn capability(&self) -> Capability {
112        self.capability
113    }
114
115    async fn create_dir(
116        &self,
117        _: &OperationContext,
118        _: &str,
119        _: OpCreateDir,
120    ) -> Result<RpCreateDir> {
121        Err(Error::new(
122            ErrorKind::Unsupported,
123            "operation is not supported",
124        ))
125    }
126
127    async fn stat(&self, _: &OperationContext, path: &str, _: OpStat) -> Result<RpStat> {
128        let p = build_abs_path(&self.root, path);
129
130        if p == build_abs_path(&self.root, "") {
131            Ok(RpStat::new(Metadata::new(EntryMode::DIR)))
132        } else {
133            match self.core.get(&p)? {
134                Some(value) => Ok(RpStat::new(value.metadata)),
135                None => Err(Error::new(
136                    ErrorKind::NotFound,
137                    "memory doesn't have this path",
138                )),
139            }
140        }
141    }
142
143    fn read(&self, _ctx: &OperationContext, path: &str, args: OpRead) -> Result<Self::Reader> {
144        Ok(oio::StreamReader::new(MemoryReader::new(
145            self.clone(),
146            path,
147            args,
148        )))
149    }
150
151    fn write(&self, _ctx: &OperationContext, path: &str, args: OpWrite) -> Result<Self::Writer> {
152        let p = build_abs_path(&self.root, path);
153        Ok(MemoryWriter::new(self.core.clone(), p, args))
154    }
155
156    fn delete(&self, _ctx: &OperationContext) -> Result<Self::Deleter> {
157        Ok(oio::OneShotDeleter::new(MemoryDeleter::new(
158            self.core.clone(),
159            self.root.clone(),
160        )))
161    }
162
163    fn list(&self, _ctx: &OperationContext, path: &str, args: OpList) -> Result<Self::Lister> {
164        let p = build_abs_path(&self.root, path);
165        let keys = self.core.scan(&p)?;
166        let lister = MemoryLister::new(&self.root, keys);
167        let lister = oio::HierarchyLister::new(lister, path, args.recursive());
168
169        Ok(lister)
170    }
171
172    fn copy(
173        &self,
174        _: &OperationContext,
175        _: &str,
176        _: &str,
177        _: OpCopy,
178        _: OpCopier,
179    ) -> Result<Self::Copier> {
180        Err(Error::new(
181            ErrorKind::Unsupported,
182            "operation is not supported",
183        ))
184    }
185
186    async fn rename(
187        &self,
188        _: &OperationContext,
189        _: &str,
190        _: &str,
191        _: OpRename,
192    ) -> Result<RpRename> {
193        Err(Error::new(
194            ErrorKind::Unsupported,
195            "operation is not supported",
196        ))
197    }
198
199    async fn presign(&self, _: &OperationContext, _: &str, _: OpPresign) -> Result<RpPresign> {
200        Err(Error::new(
201            ErrorKind::Unsupported,
202            "operation is not supported",
203        ))
204    }
205}
206
207/// Reader returned by this backend.
208pub struct MemoryReader {
209    backend: MemoryBackend,
210    path: String,
211}
212
213impl MemoryReader {
214    fn new(backend: MemoryBackend, path: &str, _: OpRead) -> Self {
215        Self {
216            backend,
217            path: path.to_string(),
218        }
219    }
220}
221
222impl oio::StreamRead for MemoryReader {
223    async fn open(&self, range: BytesRange) -> Result<(RpRead, Box<dyn oio::ReadStreamDyn>)> {
224        let backend = &self.backend;
225        let path = self.path.as_str();
226        let p = build_abs_path(&backend.root, path);
227
228        let value = match backend.core.get(&p)? {
229            Some(value) => value,
230            None => {
231                return Err(Error::new(
232                    ErrorKind::NotFound,
233                    "memory doesn't have this path",
234                ));
235            }
236        };
237
238        let total_size = value.content.len() as u64;
239        let content = value
240            .content
241            .slice(range.to_content_range(value.content.len())?);
242        let metadata = Metadata::new(EntryMode::FILE).with_content_length(total_size);
243        Ok((
244            RpRead::new(metadata),
245            Box::new(content) as Box<dyn oio::ReadStreamDyn>,
246        ))
247    }
248}
opendal_core/services/memory/backend.rs

opendal_core/services/memory/
backend.rs
