feat: Database Query Cache

1 files changed, 85 insertions, 0 deletions

diff --git a/src/util/cache/Cache.ts b/src/util/cache/Cache.ts
new file mode 100644
index 00000000..fb66c2e3
--- /dev/null
+++ b/src/util/cache/Cache.ts
@@ -0,0 +1,85 @@
+/*
+	Fosscord: A FOSS re-implementation and extension of the Discord.com backend.
+	Copyright (C) 2023 Fosscord and Fosscord Contributors
+	
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Affero General Public License as published
+	by the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+	
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Affero General Public License for more details.
+	
+	You should have received a copy of the GNU Affero General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+/* eslint-disable @typescript-eslint/ban-ts-comment */
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+import { EntityMetadata, FindOptionsWhere } from "typeorm";
+import { LocalCache } from "./LocalCache";
+
+declare module "typeorm" {
+	interface BaseEntity {
+		metadata?: EntityMetadata;
+		cache: CacheManager;
+	}
+}
+
+export type BaseEntityWithId = { id: string; [name: string]: any };
+export type Criteria =
+	| string
+	| string[]
+	| number
+	| number[]
+	| FindOptionsWhere<never>;
+
+export interface Cache {
+	get(id: string): BaseEntityWithId | undefined;
+	set(id: string, entity: BaseEntityWithId): this;
+	find(options: Record<string, never>): BaseEntityWithId | undefined;
+	filter(options: Record<string, never>): BaseEntityWithId[];
+	delete(id: string): boolean;
+}
+
+export class CacheManager {
+	// last access time to automatically remove old entities from cache after 5 minutes of inactivity (to prevent memory leaks)
+	cache: Cache;
+
+	constructor() {
+		this.cache = new LocalCache();
+		// TODO: Config.get().cache.redis;
+	}
+
+	delete(id: string) {
+		return this.cache.delete(id);
+	}
+
+	insert(entity: BaseEntityWithId) {
+		if (!entity.id) return;
+
+		return this.cache.set(entity.id, entity);
+	}
+
+	find(options?: Record<string, never>, select?: string[] | undefined) {
+		if (!options) return null;
+		const entity = this.cache.find(options);
+		if (!entity) return null;
+		if (!select) return entity;
+
+		const result = {};
+		for (const prop of select) {
+			// @ts-ignore
+			result[prop] = entity[prop];
+		}
+
+		// @ts-ignore
+		return entity.constructor.create(result);
+	}
+
+	filter(options: Record<string, never>) {
+		return this.cache.filter(options);
+	}
+}