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            shared: false,
83            ..Default::default()
84        };
85
86        Self {
87            info: ServiceInfo::new(MEMORY_SCHEME, "/", format!("{:p}", Arc::as_ptr(&core.data))),
88            core: Arc::new(core),
89            root: "/".to_string(),
90            capability,
91        }
92    }
93
94    fn with_normalized_root(mut self, root: String) -> Self {
95        self.info = ServiceInfo::new(MEMORY_SCHEME, root.clone(), self.info.name());
96        self.root = root;
97        self
98    }
99}
100
101impl Service for MemoryBackend {
102    type Reader = oio::StreamReader<MemoryReader>;
103    type Writer = MemoryWriter;
104    type Lister = oio::HierarchyLister<MemoryLister>;
105    type Deleter = oio::OneShotDeleter<MemoryDeleter>;
106    type Copier = ();
107
108    fn info(&self) -> ServiceInfo {
109        self.info.clone()
110    }
111
112    fn capability(&self) -> Capability {
113        self.capability
114    }
115
116    async fn create_dir(
117        &self,
118        _: &OperationContext,
119        _: &str,
120        _: OpCreateDir,
121    ) -> Result<RpCreateDir> {
122        Err(Error::new(
123            ErrorKind::Unsupported,
124            "operation is not supported",
125        ))
126    }
127
128    async fn stat(&self, _: &OperationContext, path: &str, _: OpStat) -> Result<RpStat> {
129        let p = build_abs_path(&self.root, path);
130
131        if p == build_abs_path(&self.root, "") {
132            Ok(RpStat::new(Metadata::new(EntryMode::DIR)))
133        } else {
134            match self.core.get(&p)? {
135                Some(value) => Ok(RpStat::new(value.metadata)),
136                None => Err(Error::new(
137                    ErrorKind::NotFound,
138                    "memory doesn't have this path",
139                )),
140            }
141        }
142    }
143
144    fn read(&self, _ctx: &OperationContext, path: &str, args: OpRead) -> Result<Self::Reader> {
145        Ok(oio::StreamReader::new(MemoryReader::new(
146            self.clone(),
147            path,
148            args,
149        )))
150    }
151
152    fn write(&self, _ctx: &OperationContext, path: &str, args: OpWrite) -> Result<Self::Writer> {
153        let p = build_abs_path(&self.root, path);
154        Ok(MemoryWriter::new(self.core.clone(), p, args))
155    }
156
157    fn delete(&self, _ctx: &OperationContext) -> Result<Self::Deleter> {
158        Ok(oio::OneShotDeleter::new(MemoryDeleter::new(
159            self.core.clone(),
160            self.root.clone(),
161        )))
162    }
163
164    fn list(&self, _ctx: &OperationContext, path: &str, args: OpList) -> Result<Self::Lister> {
165        let p = build_abs_path(&self.root, path);
166        let keys = self.core.scan(&p)?;
167        let lister = MemoryLister::new(&self.root, keys);
168        let lister = oio::HierarchyLister::new(lister, path, args.recursive());
169
170        Ok(lister)
171    }
172
173    fn copy(
174        &self,
175        _: &OperationContext,
176        _: &str,
177        _: &str,
178        _: OpCopy,
179        _: OpCopier,
180    ) -> Result<Self::Copier> {
181        Err(Error::new(
182            ErrorKind::Unsupported,
183            "operation is not supported",
184        ))
185    }
186
187    async fn rename(
188        &self,
189        _: &OperationContext,
190        _: &str,
191        _: &str,
192        _: OpRename,
193    ) -> Result<RpRename> {
194        Err(Error::new(
195            ErrorKind::Unsupported,
196            "operation is not supported",
197        ))
198    }
199
200    async fn presign(&self, _: &OperationContext, _: &str, _: OpPresign) -> Result<RpPresign> {
201        Err(Error::new(
202            ErrorKind::Unsupported,
203            "operation is not supported",
204        ))
205    }
206}
207
208/// Reader returned by this backend.
209pub struct MemoryReader {
210    backend: MemoryBackend,
211    path: String,
212}
213
214impl MemoryReader {
215    fn new(backend: MemoryBackend, path: &str, _: OpRead) -> Self {
216        Self {
217            backend,
218            path: path.to_string(),
219        }
220    }
221}
222
223impl oio::StreamRead for MemoryReader {
224    async fn open(&self, range: BytesRange) -> Result<(RpRead, Box<dyn oio::ReadStreamDyn>)> {
225        let backend = &self.backend;
226        let path = self.path.as_str();
227        let p = build_abs_path(&backend.root, path);
228
229        let value = match backend.core.get(&p)? {
230            Some(value) => value,
231            None => {
232                return Err(Error::new(
233                    ErrorKind::NotFound,
234                    "memory doesn't have this path",
235                ));
236            }
237        };
238
239        let total_size = value.content.len() as u64;
240        let content = value
241            .content
242            .slice(range.to_content_range(value.content.len())?);
243        let metadata = Metadata::new(EntryMode::FILE).with_content_length(total_size);
244        Ok((
245            RpRead::new(metadata),
246            Box::new(content) as Box<dyn oio::ReadStreamDyn>,
247        ))
248    }
249}
opendal_core/services/memory/backend.rs

opendal_core/services/memory/
backend.rs
