bin/src/io.rs
Jordan Johnson-Doyle 09e411739a
Run cargo fmt
2019-02-15 22:01:22 +00:00

72 lines
2 KiB
Rust

extern crate gpw;
extern crate linked_hash_map;
extern crate rand;
use rand::distributions::Alphanumeric;
use rand::{thread_rng, Rng};
use linked_hash_map::LinkedHashMap;
use std::cell::RefCell;
use std::env;
use std::sync::RwLock;
lazy_static! {
static ref ENTRIES: RwLock<LinkedHashMap<String, String>> = RwLock::new(LinkedHashMap::new());
static ref BUFFER_SIZE: usize = env::var("BIN_BUFFER_SIZE")
.map(|f| f
.parse::<usize>()
.expect("Failed to parse value of BIN_BUFFER_SIZE"))
.unwrap_or(1000usize);
}
/// Ensures `ENTRIES` is less than the size of `BIN_BUFFER_SIZE`. If it isn't then
/// `ENTRIES.len() - BIN_BUFFER_SIZE` elements will be popped off the front of the map.
///
/// During the purge, `ENTRIES` is locked and the current thread will block.
fn purge_old() {
let entries_len = ENTRIES.read().unwrap_or_else(|p| p.into_inner()).len();
if entries_len > *BUFFER_SIZE {
let to_remove = entries_len - *BUFFER_SIZE;
let mut entries = ENTRIES.write().unwrap_or_else(|p| p.into_inner());
for _ in 0..to_remove {
entries.pop_front();
}
}
}
/// Generates a 'pronounceable' random ID using gpw
pub fn generate_id() -> String {
thread_local!(static KEYGEN: RefCell<gpw::PasswordGenerator> = RefCell::new(gpw::PasswordGenerator::default()));
KEYGEN.with(|k| {
k.borrow_mut().next().unwrap_or_else(|| {
thread_rng()
.sample_iter(&Alphanumeric)
.take(6)
.collect::<String>()
})
})
}
/// Stores a paste under the given id
pub fn store_paste(id: String, content: String) {
purge_old();
ENTRIES
.write()
.unwrap_or_else(|p| p.into_inner())
.insert(id, content);
}
/// Get a paste by id.
///
/// Returns `None` if the paste doesn't exist.
pub fn get_paste(id: &str) -> Option<String> {
ENTRIES
.read()
.unwrap_or_else(|p| p.into_inner())
.get(id)
.cloned()
}