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@ChrisChares
ChrisChares / AsyncAwaitGenerator.md
Last active September 30, 2022 13:26
async/await with ES6 Generators & Promises

async/await with ES6 Generators & Promises

This vanilla ES6 function async allows code to yield (i.e. await) the asynchronous result of any Promise within. The usage is almost identical to ES7's async/await keywords.

async/await control flow is promising because it allows the programmer to reason linearly about complex asynchronous code. It also has the benefit of unifying traditionally disparate synchronous and asynchronous error handling code into one try/catch block.

This is expository code for the purpose of learning ES6. It is not 100% robust. If you want to use this style of code in the real world you might want to explore a well-tested library like co, task.js or use async/await with Babel. Also take a look at the official async/await draft section on desugaring.

Compatibility

  • node.js - 4.3.2+ (maybe earlier with
@ljharb
ljharb / array_iteration_thoughts.md
Last active October 2, 2025 14:17
Array iteration methods summarized

Array Iteration

https://gist.github.com/ljharb/58faf1cfcb4e6808f74aae4ef7944cff

While attempting to explain JavaScript's reduce method on arrays, conceptually, I came up with the following - hopefully it's helpful; happy to tweak it if anyone has suggestions.

Intro

JavaScript Arrays have lots of built in methods on their prototype. Some of them mutate - ie, they change the underlying array in-place. Luckily, most of them do not - they instead return an entirely distinct array. Since arrays are conceptually a contiguous list of items, it helps code clarity and maintainability a lot to be able to operate on them in a "functional" way. (I'll also insist on referring to an array as a "list" - although in some languages, List is a native data type, in JS and this post, I'm referring to the concept. Everywhere I use the word "list" you can assume I'm talking about a JS Array) This means, to perform a single operation on the list as a whole ("atomically"), and to return a new list - thus making it mu

@yefim
yefim / Dockerrun.aws.json
Last active July 22, 2025 01:10
Build a Docker image, push it to AWS EC2 Container Registry, then deploy it to AWS Elastic Beanstalk
{
"AWSEBDockerrunVersion": "1",
"Image": {
"Name": "<AWS_ACCOUNT_ID>.dkr.ecr.us-east-1.amazonaws.com/<NAME>:<TAG>",
"Update": "true"
},
"Ports": [
{
"ContainerPort": "443"
}
@spaze
spaze / opera-vpn.md
Last active August 23, 2025 14:02
Opera VPN behind the curtains is just a proxy, here's how it works

2023 update

ℹ️ Please note this research is from 2016 when Opera has first added their browser "VPN", even before the "Chinese deal" was closed. They have since introduced some real VPN apps but this below is not about them.

🕵️ Some folks also like to use this article to show a proof that the Opera browser is a spyware or that Opera sells all your data to 3rd parties or something like that. This article here doesn't say anything like that.


When setting up (that's immediately when user enables it in settings) Opera VPN sends few API requests to https://api.surfeasy.com to obtain credentials and proxy IPs, see below, also see The Oprah Proxy.

The browser then talks to a proxy de0.opera-proxy.net (when VPN location is set to Germany), it's IP address can only be resolved from within Opera when VPN is on, it's 185.108.219.42 (or similar, see below). It's an HTTP/S proxy which requires auth.

@jay3sh
jay3sh / guard-my-mabook-when-i-am-away.sh
Created March 30, 2016 16:46
Guard My Macbook When I'm Away
#!/bin/bash
#
# When you are working on your macbook sitting in cafe and you have to go pee,
# you need some way to guard you machine.
#
# Start this script, remove any earphones, and go do the job.
# The assumption is the thief will close the lid of the laptop before taking it away.
# This script detects the closing of the lid and plays some loud audio that will
# likely distract the thief and/or grab attention of nearby people, making the
@dmvaldman
dmvaldman / promisesEM.md
Last active June 1, 2024 00:20
Promises as EventEmitters

Promises as EventEmitters

I was trying to understand JavaScript Promises by using various libraries (bluebird, when, Q) and other async approaches.

I read the spec, some blog posts, and looked through some code. I learned how to

@aaronsama
aaronsama / README.md
Last active June 15, 2016 17:03
Star rating
@d-akara
d-akara / JavaScriptSafeNavigation.md
Last active April 11, 2024 16:18
JavaScript Safe Navigation

Experimental Safe JavaScript Navigation

Implemented using ES6 Proxies and Symbols

The purpose of this function is to provide a way to avoid deep nested conditionals when traversing a hierarchy of objects. Some languages use an operator such as '?.' to perform this capability. This is sometimes called safe navigation or null conditional operators.

You can somewhat think of this as how a xpath select works. If any nodes along the path are not found, your result is simply not found without throwing an exception and without needing to check each individual node to see if it exists.

Suggestions for improvements welcome!

The issue:

..mobile browsers will wait approximately 300ms from the time that you tap the button to fire the click event. The reason for this is that the browser is waiting to see if you are actually performing a double tap.

(from a new defunct https://developers.google.com/mobile/articles/fast_buttons article)

touch-action CSS property can be used to disable this behaviour.

touch-action: manipulation The user agent may consider touches that begin on the element only for the purposes of scrolling and continuous zooming. Any additional behaviors supported by auto are out of scope for this specification.

@antirez
antirez / wh.md
Last active November 26, 2020 07:18
For white hat hackers setting passwords to open Redis instances

Dear white hat attackers,

recently we observed a number of Redis instances that were targeted by a simple attack, consisting in setting a password using the CONFIG SET requirepass <password> command to instances which are left open on the internet.

This is, in my opinion, a good idea, since those Redis instances are going to be cracked anyway. I believe you are doing this in order to make Redis users aware they forgot to setup firewalling rules in order to make their instances not reachable from the outside.