You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
101 lines
2.9 KiB
101 lines
2.9 KiB
// Copyright 2015 Drew Short <drew@sothr.com>.
|
|
//
|
|
// Licensed under the MIT license<LICENSE-MIT or http://opensource.org/licenses/MIT>.
|
|
// This file may not be copied, modified, or distributed except according to those terms.
|
|
|
|
extern crate image;
|
|
extern crate sha1;
|
|
|
|
use self::image::ImageBuffer;
|
|
use self::sha1::Sha1;
|
|
use std::path::Path;
|
|
use std::fs::{File, create_dir_all};
|
|
use std::io::{Read, Error};
|
|
use std::option::Option;
|
|
use std::result::Result;
|
|
|
|
const CACHE_DIR: &'static str = "./.hash_cache";
|
|
const CACHE_FILE_EXT: &'static str = "png";
|
|
|
|
// Creates the required directories
|
|
pub fn prep_cache() -> Result<(), Error> {
|
|
create_dir_all(CACHE_DIR)
|
|
}
|
|
|
|
/**
|
|
* Get the hash of the desired file and return it as a hex string
|
|
*/
|
|
fn get_file_hash(path: &Path) -> Result<String, Error> {
|
|
let mut source = try!(File::open(&path));
|
|
let mut buf: Vec<u8> = Vec::new();
|
|
try!(source.read_to_end(&mut buf));
|
|
let mut sha1 = Sha1::new();
|
|
sha1.update(&buf);
|
|
// Return the hex result of the hash
|
|
Ok(sha1.hexdigest())
|
|
}
|
|
|
|
/**
|
|
* Put an image buffer in the cache
|
|
*/
|
|
pub fn put_in_cache(path: &Path, image: &ImageBuffer<image::Luma<u8>, Vec<u8>>) {
|
|
let hash = get_file_hash(&path);
|
|
match hash {
|
|
Ok(sha1) => {
|
|
let cache_path_str = format!("{}/{}.{}",CACHE_DIR, sha1, CACHE_FILE_EXT);
|
|
let cached_path = Path::new(&cache_path_str);
|
|
// Save the file into the cache
|
|
match image.save(cached_path) {
|
|
Ok(_) => {},
|
|
Err(e) => println!("Error: {}", e),
|
|
}
|
|
},
|
|
Err(e) => println!("Error: {}", e),
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Get an image buffer out of the cache
|
|
*/
|
|
pub fn get_from_cache(path: &Path) -> Option<ImageBuffer<image::Luma<u8>, Vec<u8>>> {
|
|
let hash = get_file_hash(&path);
|
|
match hash {
|
|
Ok(sha1) => {
|
|
// Check if the file exists in the cache
|
|
let cache_path_str = format!("{}/{}.{}",CACHE_DIR, sha1, CACHE_FILE_EXT);
|
|
let cached_path = Path::new(&cache_path_str);
|
|
// Try to open, if it does, then we can read the image in
|
|
match File::open(&cached_path) {
|
|
Ok(_) => {
|
|
let image = image::open(&cached_path).unwrap();
|
|
Some(image.to_luma())
|
|
},
|
|
Err(e) => {
|
|
println!("Error: {}", e);
|
|
None
|
|
},
|
|
}
|
|
},
|
|
Err(e) => {
|
|
println!("Error: {}", e);
|
|
None
|
|
},
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_get_file_hash() {
|
|
let target = "test_images/sample_01_large.jpg";
|
|
let target_path = Path::new(target);
|
|
let hash = get_file_hash(&target_path);
|
|
match hash {
|
|
Ok(v) => {
|
|
println!("Hash: {}", v);
|
|
assert!(v == "4beb6f2d852b75a313863916a1803ebad13a3196");
|
|
}
|
|
Err(e) => {
|
|
println!("Error: {:?}", e);
|
|
assert!(false);
|
|
}
|
|
}
|
|
}
|