hardlounge/src/plugins/storage.js
2019-07-19 11:27:40 +01:00

85 lines
2.0 KiB
JavaScript

"use strict";
const log = require("../log");
const fs = require("fs");
const fsextra = require("fs-extra");
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.
fsextra.emptyDirSync(helper.getStoragePath());
}
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);
}
fsextra
.ensureDir(folder)
.then(() => {
fs.writeFile(filePath, data, (err) => {
if (err) {
log.error("Failed to store a file", err);
return callback("");
}
callback(url);
});
})
.catch((err) => {
log.error("Failed to create storage folder", err);
return callback("");
});
}
}
module.exports = new Storage();