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#[macro_use]
extern crate serde_derive;
extern crate recurdates;
extern crate bincode;
extern crate leveldb;
extern crate chrono;
use std::path::Path;
use leveldb::kv::KV;
use leveldb::iterator::Iterable;
use leveldb::database::{self, Database};
use leveldb::options::{Options, WriteOptions, ReadOptions};
use bincode::{serialize, deserialize, Infinite};
pub mod task;
use task::Task;
pub mod error;
use error::RustlerError;
#[cfg(test)]
mod tests;
pub struct Rustler {
database: Database<i32>,
}
pub struct TaskIterator<'a> {
iterator: database::iterator::Iterator<'a, i32>,
}
impl Rustler {
pub fn open(path: &str) -> Rustler {
let mut options = Options::new();
options.create_if_missing = true;
Rustler {
database: Database::open(Path::new(path), options)
.expect("Unable to open database."),
}
}
pub fn has(&self, tid: i32) -> bool {
let r = self.database.get(ReadOptions::new(), tid);
r.is_ok() && r.unwrap().is_some()
}
pub fn get(&self, tid: i32) -> Result<Task, RustlerError> {
self.database.get(ReadOptions::new(), tid)
.map_err(RustlerError::DBError)?
.ok_or(RustlerError::NoTaskError(tid))
.map(|x| deserialize::<Task>(&x).unwrap())
}
pub fn delete(&self, tid: i32) -> Result<(), RustlerError> {
if self.has(tid) {
self.database.delete(WriteOptions::new(), tid)
.map_err(RustlerError::DBError)
} else {
Err(RustlerError::NoTaskError(tid))
}
}
pub fn update(&self, t: &mut Task) -> Result<(), RustlerError> {
let mut tmp = std::i32::MIN;
if t.id.is_none() {
while self.has(tmp) {
tmp += 1;
}
t.id = Some(tmp);
}
let tmp_at = t.at;
t.at = None;
let st = serialize(&t, Infinite).unwrap();
t.at = tmp_at;
self.database.put(WriteOptions::new(), t.id.unwrap(), &st)
.map_err(RustlerError::DBError)
}
pub fn iter(&self) -> TaskIterator {
TaskIterator { iterator: self.database.iter(ReadOptions::new()) }
}
}
impl<'a> Iterator for TaskIterator<'a> {
type Item = Task;
fn next(&mut self) -> Option<Self::Item> {
self.iterator.next().map(|(_, v)| deserialize::<Task>(&v).unwrap())
}
}