recap/node_modules/@start9labs/start-sdk/package/lib/mainFn/Daemon.js

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Daemon = void 0;
const asError_1 = require("../../../base/lib/util/asError");
const logErrorOnce_1 = require("../../../base/lib/util/logErrorOnce");
const util_1 = require("../util");
const CommandController_1 = require("./CommandController");
const TIMEOUT_INCREMENT_MS = 1000;
const MAX_TIMEOUT_MS = 30000;
/**
 * A managed long-running process wrapper around {@link CommandController}.
 *
 * When started, the daemon automatically restarts its underlying command on failure
 * with exponential backoff (up to 30 seconds). When stopped, the command is terminated
 * gracefully. Implements {@link Drop} for automatic cleanup when the context is left.
 *
 * @typeParam Manifest - The service manifest type
 * @typeParam C - The subcontainer type, or `null` for JS-only daemons
 */
class Daemon extends util_1.Drop {
    constructor(subcontainer, startCommand, oneshot = false) {
        super();
        this.subcontainer = subcontainer;
        this.startCommand = startCommand;
        this.oneshot = oneshot;
        this.commandController = null;
        this.exitedSuccess = false;
        this.onExitFns = [];
        this.loop = null;
        this._managed = false;
    }
    /** Returns true if this daemon is a one-shot process (exits after success) */
    isOneshot() {
        return this.oneshot;
    }
    /**
     * Factory method to create a new Daemon.
     *
     * Returns a curried function: `(effects, subcontainer, exec) => Daemon`.
     * Registers an `onLeaveContext` callback that terminates the daemon when the
     * effects context is left.
     */
    static of() {
        return (effects, subcontainer, exec) => {
            let subc = subcontainer;
            if (subcontainer && subcontainer.isOwned())
                subc = subcontainer.rc();
            const startCommand = () => CommandController_1.CommandController.of()(effects, (subc?.rc() ?? null), exec);
            const res = new Daemon(subc, startCommand);
            effects.onLeaveContext(() => {
                if (!res._managed) {
                    res.term({ destroySubcontainer: true }).catch((e) => (0, logErrorOnce_1.logErrorOnce)(e));
                }
            });
            return res;
        };
    }
    /**
     * Start the daemon. If it is already running, this is a no-op.
     *
     * The daemon will automatically restart on failure with increasing backoff
     * until {@link term} is called.
     */
    async start() {
        if (this.loop) {
            return;
        }
        const abort = new AbortController();
        const done = this.runLoop(abort.signal);
        this.loop = { abort, done };
    }
    async runLoop(signal) {
        let timeoutCounter = 0;
        try {
            while (!signal.aborted) {
                if (this.commandController) {
                    await this.commandController.term({}).catch(logErrorOnce_1.logErrorOnce);
                    this.commandController = null;
                }
                try {
                    this.commandController = await this.startCommand();
                    if (signal.aborted) {
                        await this.commandController.term({}).catch(logErrorOnce_1.logErrorOnce);
                        this.commandController = null;
                        break;
                    }
                    const success = await this.commandController.wait().then((_) => true, (err) => {
                        if (!signal.aborted)
                            (0, logErrorOnce_1.logErrorOnce)(err);
                        return false;
                    });
                    this.commandController = null;
                    if (signal.aborted)
                        break;
                    for (const fn of this.onExitFns) {
                        try {
                            fn(success);
                        }
                        catch (e) {
                            console.error('EXIT handler', e);
                        }
                    }
                    if (success && this.oneshot) {
                        this.exitedSuccess = true;
                        break;
                    }
                }
                catch (e) {
                    if (!signal.aborted)
                        console.error(e);
                }
                if (signal.aborted)
                    break;
                await new Promise((resolve) => {
                    const timer = setTimeout(resolve, timeoutCounter);
                    signal.addEventListener('abort', () => {
                        clearTimeout(timer);
                        resolve();
                    }, { once: true });
                });
                timeoutCounter += TIMEOUT_INCREMENT_MS;
                timeoutCounter = Math.min(MAX_TIMEOUT_MS, timeoutCounter);
            }
        }
        finally {
            this.loop = null;
        }
    }
    /**
     * Terminate the daemon, stopping its underlying command.
     *
     * Sends the configured signal (default SIGTERM) and waits for the process to exit.
     * Optionally destroys the subcontainer after termination.
     *
     * @param termOptions - Optional termination settings
     * @param termOptions.signal - The signal to send (default: SIGTERM)
     * @param termOptions.timeout - Milliseconds to wait before SIGKILL
     * @param termOptions.destroySubcontainer - Whether to destroy the subcontainer after exit
     */
    async term(termOptions) {
        this.exitedSuccess = false;
        this.onExitFns = [];
        if (this.loop) {
            this.loop.abort.abort();
        }
        const exiting = this.commandController?.term({ ...termOptions });
        this.commandController = null;
        if (exiting)
            await exiting.catch(logErrorOnce_1.logErrorOnce);
        if (this.loop) {
            await this.loop.done;
        }
        if (termOptions?.destroySubcontainer) {
            await this.subcontainer?.destroy();
        }
    }
    /**
     * Mark this daemon as managed by a {@link Daemons} instance.
     * Suppresses the individual `onLeaveContext` termination since the
     * `Daemons` instance handles ordered shutdown.
     */
    markManaged() {
        this._managed = true;
    }
    /** Get a reference-counted handle to the daemon's subcontainer, or null if there is none */
    subcontainerRc() {
        return this.subcontainer?.rc() ?? null;
    }
    /** Check whether this daemon shares the same subcontainer as another daemon */
    sharesSubcontainerWith(other) {
        return this.subcontainer?.guid === other.subcontainer?.guid;
    }
    /**
     * Register a callback to be invoked each time the daemon's process exits.
     * @param fn - Callback receiving `true` on clean exit, `false` on error
     */
    onExit(fn) {
        this.onExitFns.push(fn);
    }
    onDrop() {
        this.term().catch((e) => (0, logErrorOnce_1.logErrorOnce)((0, asError_1.asError)(e)));
    }
}
exports.Daemon = Daemon;
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