cordis/client/webapp/resource-ram-cache.ts
2021-10-30 12:26:41 -05:00

52 lines
2.1 KiB
TypeScript

import * as electronRemote from '@electron/remote';
const electronConsole = electronRemote.getGlobal('console') as Console;
import Logger from '../../logger/logger';
const LOG = new Logger('resource-cache', electronConsole);
import Globals from './globals';
class ShouldNeverHappenError extends Error {
constructor(...args: any[]) {
super(...args);
this.name = 'ShouldNeverHappenError';
}
}
export default class ResourceRAMCache {
static _data = new Map(); // (serverId, resourceId) -> { resource, lastUsed }
static _size = 0;
static putResource(serverId: string, resourceId: string, resourceBuff: Buffer): void {
if (resourceBuff.length > Globals.MAX_RESOURCE_SIZE) { // skip resources if they would flood the cache
return;
}
let id = `s#${serverId}/r#${resourceId}`;
ResourceRAMCache._data.set(id, { resource: resourceBuff, lastUsed: new Date() });
ResourceRAMCache._size += resourceBuff.length;
if (ResourceRAMCache._size > Globals.MAX_SERVER_RESOURCE_CACHE_SIZE) { // TODO: this feature needs to be tested
let entries = Array.from(ResourceRAMCache._data.entries())
.map(([ key, value ]) => { return { id: key, value: value }; })
.sort((a, b) => b.value.lastUsed - a.value.lastUsed); // oldest last (for pop)
while (ResourceRAMCache._size > Globals.MAX_SERVER_RESOURCE_CACHE_SIZE) {
let entry = entries.pop();
if (entry === undefined) throw new ShouldNeverHappenError('No entry in the array but the ram cache still has a size...');
ResourceRAMCache._data.delete(entry.id);
ResourceRAMCache._size -= entry.value.resource.length;
}
}
}
static getResource(serverId: string, resourceId: string): Buffer | null {
let id = `s#${serverId}/r#${resourceId}`;
if (!ResourceRAMCache._data.has(id)) {
return null;
}
let v = ResourceRAMCache._data.get(id);
v.lastUsed = new Date();
return v.resourceBuff;
}
}
module.exports = ResourceRAMCache;