futures-cache
Futures-aware cache implementation backed by RocksDB.
State
The state of the library is:
- API is limited to only
wrap
, which includes a timeout (#1).
- Requests are currently racing in the
wrap
method, so multiple unecessary requests might occur when they should instead be queueing up (#2).
- Entries only expire when the library is loaded (#3).
- Only storage backend is RocksDB (#4).
Usage
This library requires the user to add the following dependencies to use:
futures-cache = "0.2.0"
serde = {version = "1.0.97", features = ["derive"]}
chrono = {version = "0.4.7", features = ["serde"]}
rocksdb = "0.12.2"
You'll also have to install LLVM and clang since these are build dependencies for RocksDB.
You can get them at: http://releases.llvm.org/download.html.
Examples
use std::{path::Path, fs, error::Error, sync::Arc};
use rocksdb;
use futures_cache::Cache;
use futures;
use chrono::Duration;
use serde::{Serialize, Deserialize};
enum Key<'a> {
GetUser(&'a str),
}
fn setup_db() -> Result<Arc<rocksdb::DB>, Box<dyn Error>> {
let path = Path::new("path/to/cache");
if !path.is_dir() {
fs::create_dir_all(path)?;
}
let mut options = rocksdb::Options::default();
options.set_compression_type(rocksdb::DBCompressionType::Snappy);
options.set_keep_log_file_num(16);
options.create_if_missing(true);
Ok(Arc::new(rocksdb::DB::open(&options, path)?))
}
fn main() -> Result<(), Box<dyn Error>> {
let db = setup_db()?;
let cache = Cache::load(db.clone())?;
let api = Api::new()?;
futures::executor::block_on(async move {
let mary = cache.wrap(Key::GetUser("mary"), Duration::hours(12), api.get_user("mary")).await?;
let mary2 = cache.wrap(Key::GetUser("mary"), Duration::hours(12), api.get_user("mary")).await?;
});
}