Duong Quang Duc dqduc

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.

Installing OpenSSH 7.4 on Ubuntu 16.04

sudo apt install -y build-essential libssl-dev zlib1g-dev
wget "http://mirrors.evowise.com/pub/OpenBSD/OpenSSH/portable/openssh-7.4p1.tar.gz"
tar xfz openssh-7.4p1.tar.gz
cd openssh-7.4p1
./configure
make
sudo make install

Details of steps I took on each node in a nine node ES cluster on RHEL7. These steps need to occur one node at a time, i.e. "rolling upgrade")

Step 1: Disable shard allocation

curl -XPUT "http://localhost:9200/_cluster/settings" -d'
{
  "transient": {
    "cluster.routing.allocation.enable": "none"
  }
}'

##TUNING##

Configuration

System: set file descriptors to 32K or 64K

vim /etc/security/limit.conf

	# Copyright 2019, Alexander Hass
	# https://www.hass.de/content/setup-microsoft-windows-or-iis-ssl-perfect-forward-secrecy-and-tls-12
	#
	# After running this script the computer only supports:
	# - TLS 1.2
	#
	# Version 3.0.1, see CHANGELOG.txt for changes.

	Write-Host 'Configuring IIS with SSL/TLS Deployment Best Practices...'
	Write-Host '--------------------------------------------------------------------------------'

	# http://stackoverflow.com/questions/1388025/how-to-get-id-of-the-last-updated-row-in-mysql

	# single row update
	SET @update_id := 0;
	UPDATE some_table SET column_name = 'value', id = (SELECT @update_id := id)
	WHERE some_other_column = 'blah' LIMIT 1;
	SELECT @update_id;

	# Multiple rows updated
	SET @uids := null;

	var AWS = require('aws-sdk');
	exports.handler = function(event, context) {
	var ec2 = new AWS.EC2({region: 'us-east-1'});
	ec2.startInstances({InstanceIds : ['i-0114833f8ffc9151c'] },function (err, data) {
	if (err) console.log(err, err.stack);
	else console.log(data);
	context.done(err,data);
	});
	};

	<?xml version="1.0" encoding="utf-8"?>
	<Project DefaultTargets="PrepareStaticContent" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
	<PropertyGroup>
	<!-- Passed in Parameters -->
	<configuration></configuration>
	<workingDir></workingDir>
	<buildNumber></buildNumber>
	<buildViews>false</buildViews>
	<minifyJs>true</minifyJs>
	<TargetsDirectory></TargetsDirectory>

	Remove-ItemProperty -Path HKLM:\Software\Microsoft\Fusion -Name ForceLog
	Remove-ItemProperty -Path HKLM:\Software\Microsoft\Fusion -Name LogFailures
	Remove-ItemProperty -Path HKLM:\Software\Microsoft\Fusion -Name LogResourceBinds
	Remove-ItemProperty -Path HKLM:\Software\Microsoft\Fusion -Name LogPath

	public string GetVirtualPath(VirtualPathContext context)
	{
	foreach (var matcherParameter in _matcher.Template.Parameters)
	{
	context.Values.Remove(matcherParameter.Name); // make sure none of the domain-placeholders are appended as query string parameters
	}

	return _innerRoute.GetVirtualPath(context);
	}