Evan Hu wzhudev

So you want to write a sync system for a web app with offline and realtime support? Good luck. You might find the following resources useful.

Overview articles

Database in a browser, a spec (Stepan Parunashvili)

What problem are we trying to solve with a sync system?
The web of tomorrow (Nikita Prokopov)

Compilation + Runtime

Angular

Runtime

Implementations based on reflect-metadata

Information in this Gist originally from this github issue, which is outdated.

As @RomanMinkin mentioned, you can also consider Casbin (https://github.com/casbin/casbin). It is the most starred authorization library in Golang. There are several differences between Casbin and OPA.

Feature	Casbin	OPA
Library or service?	Library/Service	Library/Service
How to write policy?	Two parts: model and policy. Model is general authorization logic. Policy is concrete policy rule.	A single part: Rego
RBAC hierarchy	Casbin supports role hierarchy (a role can have a sub-role)	Role hierarchies can be encoded in data. Also with the new `graph.reachable()` built-in function queries over those hierarchies are much more feasible now.
RBAC separation of duties	Not supported	Supported: two roles cannot be assigned together

How to use

In iTerm2, in the menu bar go to Scripts > Manage > New Python Script

Select Basic. Select Long-Running Daemon

Give the script a decent name (I chose auto_dark_mode.py)

Save and open the script in your editor of choice.

Scaling your API with rate limiters

The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

Request rate limiter

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.

Problem: How can we preprocess JavaScript (at build-time or on the server-side) so engines like V8 don't have to spend as much time in Parse? This is a topic that involves generating either bytecode or a bytecode-like-abstraction that an engine would need to accept. For folks that don't know, modern web apps typically spend a lot longer in Parsing & Compiling JS than you may think.

Yoav: This can particularly be an issue on mobile. Same files getting parsed all the time for users. Theoretically if we moved the parsing work to the server-side, we would have to worry about it less.
One angle to this problem is we all ship too much JavaScript. That's one perspective. We could also look at preprocessing.
We've been talking about this topic over the last few weeks a bit with V8. There were three main options proposed.
1. Similar to what optimize-js does. Identify IIFEs and mark them as such so the browser and VMs heuristics will catch them and do a better job than today. optimize-js only tackles IIFE bu

Inspired by dannyfritz/commit-message-emoji

	/**
	* @param {number[]} nums
	* @param {number} target
	* @return {number[]}
	*/
	var twoSum = function(nums, target) {
	/**
	* Map number to its position.
	*/
	const map = {

	/*
	* Regular expression implementation.
	* Supports only ( \| ) * + ?. No escapes.
	* Compiles to NFA and then simulates NFA
	* using Thompson's algorithm.
	*
	* See also http://swtch.com/~rsc/regexp/ and
	* Thompson, Ken. Regular Expression Search Algorithm,
	* Communications of the ACM 11(6) (June 1968), pp. 419-422.
	*

Commit type	Emoji
Initial commit	🎉 `:tada:`
Version tag	🔖 `:bookmark:`
New feature	✨ `:sparkles:`
Bugfix	🐛 `:bug:`


	git log --author="Linus Torvalds" --date=iso \| perl -nalE 'if (/^Date:\s+[\d-]{10}\s(\d{2})/) { say $1+0 }' \| sort \| uniq -c\|perl -MList::Util=max -nalE '$h{$F[1]} = $F[0]; }{ $m = max values %h; foreach (0..23) { $h{$_} = 0 if not exists $h{$_} } foreach (sort {$a <=> $b } keys %h) { say sprintf "%02d - %4d %s", $_, $h{$_}, ""x ($h{$_} / $m 50); }'