/var/www/greso.tech/server/nsm/node_modules/@grpc/grpc-js/src
Edit: /var/www/greso.tech/server/nsm/node_modules/@grpc/grpc-js/src/backoff-timeout.ts (4719B)
/*
* Copyright 2019 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
const INITIAL_BACKOFF_MS = 1000;
const BACKOFF_MULTIPLIER = 1.6;
const MAX_BACKOFF_MS = 120000;
const BACKOFF_JITTER = 0.2;
/**
* Get a number uniformly at random in the range [min, max)
* @param min
* @param max
*/
function uniformRandom(min: number, max: number) {
return Math.random() * (max - min) + min;
}
export interface BackoffOptions {
initialDelay?: number;
multiplier?: number;
jitter?: number;
maxDelay?: number;
}
export class BackoffTimeout {
/**
* The delay time at the start, and after each reset.
*/
private readonly initialDelay: number = INITIAL_BACKOFF_MS;
/**
* The exponential backoff multiplier.
*/
private readonly multiplier: number = BACKOFF_MULTIPLIER;
/**
* The maximum delay time
*/
private readonly maxDelay: number = MAX_BACKOFF_MS;
/**
* The maximum fraction by which the delay time can randomly vary after
* applying the multiplier.
*/
private readonly jitter: number = BACKOFF_JITTER;
/**
* The delay time for the next time the timer runs.
*/
private nextDelay: number;
/**
* The handle of the underlying timer. If running is false, this value refers
* to an object representing a timer that has ended, but it can still be
* interacted with without error.
*/
private timerId: NodeJS.Timer;
/**
* Indicates whether the timer is currently running.
*/
private running = false;
/**
* Indicates whether the timer should keep the Node process running if no
* other async operation is doing so.
*/
private hasRef = true;
/**
* The time that the currently running timer was started. Only valid if
* running is true.
*/
private startTime: Date = new Date();
constructor(private callback: () => void, options?: BackoffOptions) {
if (options) {
if (options.initialDelay) {
this.initialDelay = options.initialDelay;
}
if (options.multiplier) {
this.multiplier = options.multiplier;
}
if (options.jitter) {
this.jitter = options.jitter;
}
if (options.maxDelay) {
this.maxDelay = options.maxDelay;
}
}
this.nextDelay = this.initialDelay;
this.timerId = setTimeout(() => {}, 0);
clearTimeout(this.timerId);
}
private runTimer(delay: number) {
clearTimeout(this.timerId);
this.timerId = setTimeout(() => {
this.callback();
this.running = false;
}, delay);
if (!this.hasRef) {
this.timerId.unref?.();
}
}
/**
* Call the callback after the current amount of delay time
*/
runOnce() {
this.running = true;
this.startTime = new Date();
this.runTimer(this.nextDelay);
const nextBackoff = Math.min(
this.nextDelay * this.multiplier,
this.maxDelay
);
const jitterMagnitude = nextBackoff * this.jitter;
this.nextDelay =
nextBackoff + uniformRandom(-jitterMagnitude, jitterMagnitude);
}
/**
* Stop the timer. The callback will not be called until `runOnce` is called
* again.
*/
stop() {
clearTimeout(this.timerId);
this.running = false;
}
/**
* Reset the delay time to its initial value. If the timer is still running,
* retroactively apply that reset to the current timer.
*/
reset() {
this.nextDelay = this.initialDelay;
if (this.running) {
const now = new Date();
const newEndTime = this.startTime;
newEndTime.setMilliseconds(newEndTime.getMilliseconds() + this.nextDelay);
clearTimeout(this.timerId);
if (now < newEndTime) {
this.runTimer(newEndTime.getTime() - now.getTime());
} else {
this.running = false;
}
}
}
/**
* Check whether the timer is currently running.
*/
isRunning() {
return this.running;
}
/**
* Set that while the timer is running, it should keep the Node process
* running.
*/
ref() {
this.hasRef = true;
this.timerId.ref?.();
}
/**
* Set that while the timer is running, it should not keep the Node process
* running.
*/
unref() {
this.hasRef = false;
this.timerId.unref?.();
}
}