isla_lib/
cache.rs

1// BSD 2-Clause License
2//
3// Copyright (c) 2019, 2020 Alasdair Armstrong
4//
5// All rights reserved.
6//
7// Redistribution and use in source and binary forms, with or without
8// modification, are permitted provided that the following conditions are
9// met:
10//
11// 1. Redistributions of source code must retain the above copyright
12// notice, this list of conditions and the following disclaimer.
13//
14// 2. Redistributions in binary form must reproduce the above copyright
15// notice, this list of conditions and the following disclaimer in the
16// documentation and/or other materials provided with the distribution.
17//
18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30use serde::de::DeserializeOwned;
31use serde::Serialize;
32
33use std::fs::File;
34use std::path::Path;
35
36pub trait Cachekey {
37    fn key(&self) -> String;
38}
39
40pub trait Cacheable: Serialize + DeserializeOwned {
41    type Key: Cachekey;
42
43    fn from_cache<P: AsRef<Path>>(key: Self::Key, cache: P) -> Option<Self> {
44        if !cache.as_ref().is_dir() {
45            return None;
46        };
47
48        let cache_file = cache.as_ref().join(key.key());
49
50        let fd = File::open(&cache_file).ok()?;
51        bincode::deserialize_from(fd).ok()
52    }
53
54    fn cache<P: AsRef<Path>>(&self, key: Self::Key, cache: P) {
55        if !cache.as_ref().is_dir() {
56            return;
57        };
58
59        let cache_file = cache.as_ref().join(key.key());
60
61        if let Ok(fd) = File::create(&cache_file) {
62            if let Ok(()) = bincode::serialize_into(fd, self) {}
63        }
64    }
65}
isla_lib/cache.rs

isla_lib/
cache.rs
