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recap/node_modules/@start9labs/start-sdk/package/lib/mainFn/HealthDaemon.js
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189 lines
6.5 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.HealthDaemon = exports.EXIT_SUCCESS = void 0;
const defaultTrigger_1 = require("../trigger/defaultTrigger");
exports.EXIT_SUCCESS = 'EXIT_SUCCESS';
/**
* Wanted a structure that deals with controlling daemons by their health status
* States:
* -- Waiting for dependencies to be success
* -- Running: Daemon is running and the status is in the health
*
*/
class HealthDaemon {
constructor(daemon, dependencies, id, ready, effects) {
this.daemon = daemon;
this.dependencies = dependencies;
this.id = id;
this.ready = ready;
this.effects = effects;
this._health = { result: 'waiting', message: null };
this.healthWatchers = [];
this.running = false;
this.resolvedReady = false;
this.session = null;
this.readyPromise = new Promise((resolve) => (this.resolveReady = () => {
resolve();
this.resolvedReady = true;
}));
this.dependencies.forEach((d) => d.addWatcher(() => this.updateStatus()));
}
/** Run after we want to do cleanup */
async term(termOptions) {
this.healthWatchers = [];
this.running = false;
await this.stopSession();
await this.daemon?.term({
...termOptions,
});
}
/** Want to add another notifier that the health might have changed */
addWatcher(watcher) {
this.healthWatchers.push(watcher);
}
get health() {
return Object.freeze(this._health);
}
async changeRunning(newStatus) {
if (this.running === newStatus)
return;
this.running = newStatus;
if (newStatus) {
console.debug(`Launching ${this.id}...`);
this.startSession();
this.daemon?.start();
this.started = performance.now();
}
else {
console.debug(`Stopping ${this.id}...`);
await this.stopSession();
await this.daemon?.term();
}
}
async stopSession() {
if (!this.session)
return;
this.session.abort.abort();
await this.session.done;
this.session = null;
this.resetReady();
}
resetReady() {
this.resolvedReady = false;
this.readyPromise = new Promise((resolve) => (this.resolveReady = () => {
resolve();
this.resolvedReady = true;
}));
}
startSession() {
this.session?.abort.abort();
const abort = new AbortController();
this.daemon?.onExit((success) => {
if (abort.signal.aborted)
return;
if (success && this.ready === 'EXIT_SUCCESS') {
this.setHealth({ result: 'success', message: null });
}
else if (!success) {
this.setHealth({
result: 'failure',
message: `${this.id} daemon crashed`,
});
}
else if (!this.daemon?.isOneshot()) {
this.setHealth({
result: 'failure',
message: `${this.id} daemon exited`,
});
}
});
const done = this.ready === 'EXIT_SUCCESS'
? Promise.resolve()
: this.runHealthCheckLoop(abort.signal);
this.session = { abort, done };
}
async runHealthCheckLoop(signal) {
if (this.ready === 'EXIT_SUCCESS')
return;
const trigger = (this.ready.trigger ?? defaultTrigger_1.defaultTrigger)(() => ({
lastResult: this._health.result,
}));
const aborted = new Promise((resolve) => signal.addEventListener('abort', () => resolve({ done: true }), {
once: true,
}));
try {
for (let res = await Promise.race([aborted, trigger.next()]); !res.done; res = await Promise.race([aborted, trigger.next()])) {
const response = await Promise.resolve(this.ready.fn()).catch((err) => {
return {
result: 'failure',
message: 'message' in err ? err.message : String(err),
};
});
if (signal.aborted)
break;
await this.setHealth(response);
}
}
catch (err) {
if (!signal.aborted) {
console.error(`Daemon ${this.id} health check failed: ${err}`);
}
}
}
onReady() {
return this.readyPromise;
}
get isReady() {
return this.resolvedReady;
}
async setHealth(health) {
const changed = this._health.result !== health.result;
this._health = health;
if (this.resolveReady && health.result === 'success') {
this.resolveReady();
}
if (changed)
this.healthWatchers.forEach((watcher) => watcher());
if (this.ready === 'EXIT_SUCCESS')
return;
const display = this.ready.display;
if (!display) {
return;
}
let result = health.result;
if (result === 'failure' &&
this.started &&
performance.now() - this.started <= (this.ready.gracePeriod ?? 10_000))
result = 'starting';
if (result === 'failure') {
console.error(`Health Check ${this.id} failed:`, health.message);
}
await this.effects.setHealth({
...health,
id: this.id,
name: display,
result,
});
}
async updateStatus() {
const healths = this.dependencies.map((d) => ({
health: d.running && d._health,
id: d.id,
display: typeof d.ready === 'object' ? d.ready.display : null,
}));
const waitingOn = healths.filter((h) => !h.health || h.health.result !== 'success');
if (waitingOn.length)
console.debug(`daemon ${this.id} waiting on ${waitingOn.map((w) => w.id)}`);
if (waitingOn.length) {
const waitingOnNames = waitingOn.flatMap((w) => w.display ? [w.display] : []);
const message = waitingOnNames.length ? waitingOnNames.join(', ') : null;
await this.setHealth({ result: 'waiting', message });
}
else {
await this.setHealth({ result: 'starting', message: null });
}
await this.changeRunning(!waitingOn.length);
}
}
exports.HealthDaemon = HealthDaemon;
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