hardlounge/src/plugins/storage.js
2020-03-22 20:42:16 +02:00

106 lines
2.4 KiB
JavaScript

"use strict";
const log = require("../log");
const fs = require("fs");
const path = require("path");
const crypto = require("crypto");
const helper = require("../helper");
class Storage {
constructor() {
this.references = new Map();
}
emptyDir() {
// Ensures that a directory is empty.
// Deletes directory contents if the directory is not empty.
// If the directory does not exist, it is created.
const dir = helper.getStoragePath();
let items;
try {
items = fs.readdirSync(dir);
} catch (e) {
fs.mkdirSync(dir, {recursive: true});
return;
}
// TODO: Use `fs.rmdirSync(dir, {recursive: true});` when it's stable (node 13+)
items.forEach((item) => deleteFolder(path.join(dir, item)));
}
dereference(url) {
const references = (this.references.get(url) || 0) - 1;
if (references < 0) {
return log.warn("Tried to dereference a file that has no references", url);
}
if (references > 0) {
return this.references.set(url, references);
}
this.references.delete(url);
// Drop "storage/" from url and join it with full storage path
const filePath = path.join(helper.getStoragePath(), url.substring(8));
fs.unlink(filePath, (err) => {
if (err) {
log.error("Failed to delete stored file", err);
}
});
}
store(data, extension, callback) {
const hash = crypto.createHash("sha256").update(data).digest("hex");
const a = hash.substring(0, 2);
const b = hash.substring(2, 4);
const folder = path.join(helper.getStoragePath(), a, b);
const filePath = path.join(folder, `${hash.substring(4)}.${extension}`);
const url = `storage/${a}/${b}/${hash.substring(4)}.${extension}`;
this.references.set(url, 1 + (this.references.get(url) || 0));
// If file with this name already exists, we don't need to write it again
if (fs.existsSync(filePath)) {
return callback(url);
}
fs.mkdir(folder, {recursive: true}, (mkdirErr) => {
if (mkdirErr) {
log.error("Failed to create storage folder", mkdirErr);
return callback("");
}
fs.writeFile(filePath, data, (err) => {
if (err) {
log.error("Failed to store a file", err);
return callback("");
}
callback(url);
});
});
}
}
module.exports = new Storage();
function deleteFolder(dir) {
fs.readdirSync(dir).forEach((item) => {
item = path.join(dir, item);
if (fs.lstatSync(item).isDirectory()) {
deleteFolder(item);
} else {
fs.unlinkSync(item);
}
});
fs.rmdirSync(dir);
}