48 lines
1.4 KiB
TypeScript
48 lines
1.4 KiB
TypeScript
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import {Express, Router} from "express";
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import Logger from "./Logger";
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import {sleep} from "./Utils";
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export default abstract class ApplicationComponent<T> {
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private val?: T;
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public abstract async start(app: Express, router: Router): Promise<void>;
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public abstract async stop(): Promise<void>;
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protected export(val: T) {
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this.val = val;
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}
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public import(): T {
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if (!this.val) throw 'Cannot import if nothing was exported.';
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return this.val;
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}
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protected async prepare(name: string, prepare: () => Promise<void>): Promise<void> {
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let err;
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do {
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try {
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await prepare();
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err = null;
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} catch (e) {
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err = e;
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Logger.error(err, `${name} failed to prepare; retrying in 5s...`)
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await sleep(5000);
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}
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} while (err);
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Logger.info(`${name} ready!`);
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}
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protected async close(thingName: string, thing: any, fn: Function): Promise<void> {
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try {
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await new Promise((resolve, reject) => fn.call(thing, (err: any) => {
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if (err) reject(err);
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else resolve();
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}));
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Logger.info(`${thingName} closed.`);
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} catch (e) {
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Logger.error(e, `An error occurred while closing the ${thingName}.`);
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}
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}
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}
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