Kirk Haines

wyhaines@gmail.com

kirk-haines@cookpad.com

Paris.rb 2018

It's Rubies All The Way Down

The evolution of the Ruby (web) stack and an exploration of just how much of the complex modern stack can be done (effectively) with Ruby software, right now.

https://slides.com/wyhaines/its-rubies-all-the-way-down-in-paris/live

Kirk Haines

• Rubyist since 2001

• First professional Ruby web app in 2002

• Dozens of sites and apps, and several web servers since

kirk-haines@cookpad.com

wyhaines@gmail.com

@wyhaines

What is a "Stack"?

The "Stack" is the software components that live around our application, enabling it to be accessed by end users, and enabling it's own function.

Front end proxy/load balancing
Asset caching layer
Web server for static assets
App container + app itself
Database
Other data stores (key/value stores)
Deployment Architecture
Configuration Management
Log management

The Ruby Bits

Traditionally, only some of this is done with Ruby

~~Front end proxy/load balancing~~
~~Asset caching layer~~
~~Web server for static assets~~
App container + app itself
~~Database~~
~~Other data stores (key/value stores)~~
Deployment Architecture (w/ Capistrano)
Log management (w/ Fluentd)
Configuration Management (Chef, Itamae)

I've done other parts in Ruby, for Production apps, for a long time. So, let's see how we got to where we are with the modern Ruby stack, and then see how far we can push it in doing those other parts with Ruby.

Ruby For The Long Haul

https://www.ruby-lang.org/en/downloads/releases/

I started here....

Ruby 1.6.6

Gig to Write a Web App

Job Search Application for Interns

Ruby is Joy. Ruby is Love.

Let's do it with Ruby!

Stack? Frameworks?

Web Development With Ruby Was Different Then

There were no real "frameworks".

There were a few tools.

Stack options were limited.

Amrita

CGI

mod_ruby

Apache based stack

Just Templating & Embedding & CGI

Amrita

CGI

mod_ruby

Author: seki <seki@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date:   Sun Nov 17 16:11:40 2002 +0000

    * add ERB

XHTML/HTML Templating

Webserver <-> Executable protocol

Embed Ruby inside Apache

Before Rails

Before ERB

A "Ruby" Stack in 2002?

It was a hodge podge

Apache

Ruby

Script

CGI

Apache

mod_ruby

Your App

IOWA?

Avi Bryant proof-of-concept framework

Written in 2001
Proof of concept web development framework
Internet Objects for Web Applications
Component/Object based
Separation of concerns
Magic server side state management
Fast, easy, delightful
IOWA apps ran as separate, persistent processes, and handled requests via a socket...
Communication channels supported:
iowa.cgi -- any web server that supported CGI
mod_iowa -- Apache only
IOWAServlet -- WEBrick servlet to attach IOWA app to a web server
Impractical for real world apps in the state that I found it in
Avi took the concepts and implemented them in Smalltalk as the Seaside Framework

IOWA!

Architecture was much nicer than other Ruby options

Premonitions

Listening on sockets

Attaching to a web server directly

Took it over in 2002, hacked, and released a commercial application, running on Ruby, in 2002

My Ruby "stack" was evolving

Evolving Ruby Stack

Apache

w/ mod_iowa

IOWA

App

on socket

IOWA

App

on socket

IOWA

App

+ WEBrick

IOWA

App

+ WEBrick

Apache

w/ proxypass

That looks kind of modernish...

Rails!

Rails stimulated the ecosystem

Early Rails stacks still Apache centric (sometimes lighttpd)

Rails apps did run as discrete processes

FCGI

MySQL

Example: https://www.tummy.com/articles/rails-fcgi/

FCGI Bitterness

Deployment, and server management headaches

FCGI and friends (SCGI, for example) was dominant for a while, but there was a lot of unhappiness with it

Surely there must be a better way?

Mongrel

The New Hotness

https://groups.google.com/forum/#!msg/comp.lang.ruby/-cI5PtqDc1o/FXRdN9UKPE0J

Announced Jan 19, 2006

Web/Application server written in Ruby

Used a C/Ragel derived HTTP parser

Promised Speed, and delivered

Quickly became the new paradigm

Example: http://matthewcarriere.com/2008/01/18/running-ruby-on-rails-with-mongrel-clustering-and-apache-proxy/

Mongrel

The Ruby/Rails Stack Evolved

Rails + Mongrel

Rails +

Mongrel

Apache

w/ proxypass

Rails + Mongrel

Rails +

Mongrel

NGINX +

proxy

Briefly Back in IOWAland

IOWA supported multiple deployment schemes

CGI
mod_iowa
Mongrel
WEBrick
FCGI
HTTPMachine (EventMachine based HTTP server)
Built in HTTP server leveraging Mongrel's parser + EventMachine

IOWA implemented a common request specification

Not Rack; predated Rack, but similar goals

Some IOWA code ended up in Rack

Rack

March 3rd 2007: First Public Release 0.1

Agnostic interface between Ruby apps and the outside world.

It didn't change the Ruby deployment landscape immediately, but it was a key enabler

Mongrel supported Rack

Other app servers (like Thin) started being developed

Ruby devs were getting more options for their stack

More Ruby In My Stack!

Or

Why Server Side State Isn't All Puppies and Rainbows

IOWA has server side state management

REALLY nice to eliminate programmer work

However, state was isolated to a single process

All requests for a given session need to go to the same backend process

This requires sticky sessions

There was no good solution

So, the answer? Write it myself! A sticky session supporting load balancing reverse proxy, in Ruby!

More Ruby In My Stack!

Basic Webserver & Caching Reverse Proxy w/ IOWA Session Support, in Ruby?

You can't do that with Ruby

Ruby is too slow

You need C/C++/Erlang/other-fast-thing

More Ruby In My Stack!

Swiftiply!

More Ruby In My Stack!

Swiftiply!

Won't It Be Too Slow?

10k 1020 byte files, concurrency of 25; with KeepAlive
Requests per second: 26245.09 [#/sec] (mean)

10k 78000 byte files, concurrency of 25; with KeepAlive
Requests per second: 8273.98 [#/sec] (mean)

10k 78000 byte files with etag, concurrency of 25; with KeepAlive
Requests per second: 25681.19 [#/sec] (mean)

Disclosure: This was timed on a $10/month Digital Ocean instance, running

Ruby 2.5.1. The original benchmarks using Ruby 1.8.7 on cheap dedicated 2008 hardware topped out at about 15000/second.

More Ruby In My Stack!

And It Isn't Too Slow

A pure Ruby stack can do everything I need

Rack got support for Swiftiply around version 0.9

One simple, consistent stack, whether IOWA or Rails

Epiphany!!!

Pure Ruby Stack

Swiftiply

IOWA

App

IOWA

App

IOWA

App

Rails

App

Rails

App

Analogger

Circa 2009

Analogger?

Swiftiply

IOWA

App

IOWA

App

IOWA

App

Rails

App

Rails

App

Analogger

Asynchronous Logger

Many sites; many processes; logs everywhere!
Not fun when trying to find a problem or analyze traffic
No other good solution in 2007
Write it in Ruby?

Asynchronous Logger

Asynchronous; performance trumps risk of loss of a few messages on catastrophic process/server failure
API compatible with Ruby Logger
Can it be fast if it's Ruby?

Asynchronous Logger

Ruby Is Fast Enough

Analogger Speedtest -- larger messages
Testing 100000 messages of 100 bytes each.

Message rate: 130665/second (0.765315254)

Analogger Speedtest -- Fail Analogger, continue logging locally, and monitor for Analogger return, then drain queue of local logs
Testing 100000 messages of 100 bytes each.

Message rate: 61992/second (1.613111685)

Ruby Logger Speedtest (local file logging only) -- larger messages
Testing 100000 messages of 100 bytes each.

Message rate: 72811/second (1.37341377)

Asynchronous Logger

Ruby Is Fast Enough

Performance tested on $10/month Digital Ocean instance

Inexpensive dedicated 2007 era hardware, with Ruby 1.8.6/7,

delivered about 60% of those numbers. i.e. even a decade ago it was fast enough.

Still Running Today...

Swiftiply

IOWA

App

IOWA

App

IOWA

App

Rails

App

Rails

App

Analogger

Dozens of sites and apps,

large and small, running Ruby dominated production stacks for the last decade.

Room For More Ruby?

Front end proxy/load balancing
Asset caching layer
Web server for static assets
App container + app itself
Database
Other data stores (key/value stores)
Deployment
Configuration Management
Log management

You CAN do most of this with Ruby in 2018

Front End Proxy/LB

em-proxy

EM-Proxy is a DSL for writing proxies
It's been around for a long time
It's fast

https://github.com/igrigorik/em-proxy/blob/master/examples/balancing.rb

With comments, and an example/test, it's less than 200 lines to write a multi-strategy load balancing proxy with Ruby.

Front End Proxy/LB

em-proxy

  # Wrapping the proxy server
  #
  module Server
    def run(host='0.0.0.0', port=9999)

      puts ANSI::Code.bold { "Launching proxy at #{host}:#{port}...\n" }

      Proxy.start(:host => host, :port => port, :debug => false) do |conn|

        Backend.select do |backend|

          conn.server backend, :host => backend.host, :port => backend.port

          conn.on_connect  &Callbacks.on_connect
          conn.on_data     &Callbacks.on_data
          conn.on_response &Callbacks.on_response
          conn.on_finish   &Callbacks.on_finish
        end

      end
    end

    module_function :run
  end

Front End Proxy/LB

WEBrick

WEBrick is powerful, but often ignored

require 'webrick'
require 'webrick/httpproxy'

It's capable, and it's been a part of Ruby since 2002.

https://www.fedux.org/articles/2015/04/11/setup-a-proxy-with-ruby.html

Asset Caching

a special class of proxy

Really a special purpose proxy
Store HTTP responses, and deliver stored response instead of proxying, for matching requests
Just a proxy, with extra intelligence to deal with cache control and expiration of cached items

Asset Caching

Puma/Rack?

Puma is a capable web server
Rack lets us write most anything and have it work with Puma
Reasonable static asset caching on the quick and dirty with Puma and Rack?

Asset Caching

Shellacb

https://github.com/wyhaines/shellac

Puma + Rack makes it easy
More lines dedicated to the CLI than to the proxy itself
Simple to customize and expand it
Puma is fast
Rack isn't quite so fast
So, no awe inspiring speed, but maybe fast enough?

Asset Caching w/ Shellac

$ gem install shellacrb

$ shellac -s hash -b 0.0.0.0:8080 \
  -r 'parisrb2018.demos4.us::\?(.*)$::https://github.com/#{$1}' \
  -t 2:20 -w 1

Requests per second:    1861.69 [#/sec] (mean)
Time per request:       53.715 [ms] (mean)
Time per request:       0.537 [ms] (mean, across all concurrent requests)
Transfer rate:          175182.14 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.5      0       9
Processing:     2   53   3.4     53      65
Waiting:        1   53   3.8     53      65
Total:         10   53   3.0     53      65

It's probably fast enough! (Ruby 2.5.1; $5 Digital Ocean instance)

$ ab -n 10000 -c 100 http://parisrb2018.demos4.us:8080/?wyhaines

Static Asset Caching

Shellac

* Disclaimer

(i.e. the fine print)

Shellac was knocked together as a proof of concept demo for RubyKaigi and for this talk, and ABSOLUTELY needs more work and more features, and more than a few bug fixes before I'd ever use it for any real task.

Webserver For Static Assets

Ruby has a bunch of options

#! /bin/sh
read get docid junk
cat `echo "$docid" | \
  ruby -p -e '$_=$_.gsub(/^\//,"").gsub(/[\r\n]/,"").chomp'`

while :; do netcat -l -p 5000 -e ./super_simple.sh; done

Just kidding! Don't do this. Please! (It is, more or less, HTTP 0.9 compliant, though...)

Webserver For Static Assets

WEBrick

$ ruby -run -e httpd -- -p 8080 .

This actually runs a WEBrick server, and it is reasonably quick.

Requests per second:    2732.33 [#/sec] (mean)
Time per request:       3.660 [ms] (mean)
Time per request:       0.366 [ms] (mean, across all concurrent requests)
Transfer rate:          717.77 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.1      0       3
Processing:     1    4   0.5      3      17
Waiting:        0    2   0.6      2      16
Total:          1    4   0.6      4      18

Webserver For Static Assets

Puma + Rack

use Rack::Static,
  :urls => ["/"],
  :root => "."

run lambda { |env|
  [
    200,
    {
      'Content-Type'  => 'text/html',
      'Cache-Control' => 'public, max-age=86400'
    },
    ( File.open('index.html', File::RDONLY) rescue nil )
  ]
}

Requests per second:    3075.24 [#/sec] (mean)
Time per request:       3.252 [ms] (mean)
Time per request:       0.325 [ms] (mean, across all concurrent requests)
Transfer rate:          12237.88 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.1      0       2
Processing:     1    3   0.4      3      23
Waiting:        0    3   0.3      3      12
Total:          1    3   0.4      3      23

puma -b tcp://127.0.0.1:5000 -w 1 -t 2:16 ../config.ru

Webserver For Static Assets

Puma + Rack vs NGINX

Requests per second:    3075.24 [#/sec] (mean)
Time per request:       3.252 [ms] (mean)
Time per request:       0.325 [ms] (mean, across all concurrent requests)
Transfer rate:          12237.88 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.1      0       2
Processing:     1    3   0.4      3      23
Waiting:        0    3   0.3      3      12
Total:          1    3   0.4      3      23

Puma

Requests per second:    4545.14 [#/sec] (mean)
Time per request:       2.200 [ms] (mean)
Time per request:       0.220 [ms] (mean, across all concurrent requests)
Transfer rate:          18730.94 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.1      0       4
Processing:     0    2   0.4      2       7
Waiting:        0    2   0.4      2       7
Total:          1    2   0.4      2       7

NGINX

Database

This section will be short....

To my knowledge, nobody has used Ruby to implement a database (yet?)

I have a crazy idea (that I have actually started hacking on)

Ruby +

gossip type protocol +

SQLite ==

Distributed "Ruby" SQL DB!

Key / Value Store

ROMA

https://roma-kvs.org/

ROMA is a distributed key value store, written in Ruby

Fault tolerant
Pluggable back end storage modules
Easy to understand code -- it's not a lot of code
Memcached API compatible

Key / Value Store

ROMA

ROMA-1

ROMA-2

ROMA-3

$ simple_bench -t 8 -r -n 1000 10.136.73.13:11211
qps=556 max=0.151159 min=0.000541 ave=0.001797
qps=637 max=0.196910 min=0.000487 ave=0.001569
qps=605 max=0.119492 min=0.000540 ave=0.001651
qps=446 max=0.527537 min=0.000553 ave=0.002238
qps=535 max=1.563985 min=0.000483 ave=0.001866
qps=531 max=0.879976 min=0.000606 ave=0.001883
qps=599 max=0.231225 min=0.000534 ave=0.001668

Each node is a $5 Digital Ocean instance.

Writing persistent data (survives restart/reboot)

across at least 2 nodes.

Key / Value Store

ROMA

Rakuten claims performance > 10000 queries per second on in-memory data stores, using AWS instances for nodes (2015 slides)

Distributed nature and redundancy supports rolling restarts

Key / Value Store

ROMA

Ships with support for multiple storage engines:

In Memory Hash
DBM
Tokyo Cabinet
SQLite
Groonga

Extending it is as simple as writing a Ruby module to provide the implementation

Deployment

Of Course, there is Capistrano....

Capistrano is a framework for building automated deployment scripts.

Ubiqitous
Battle Tested

Deployment

Easy Git integrated deploys?

kirkhaines@MacBook-Pro ~/.ghq/github.com/wyhaines/demo-website (staging) $ git push

Git Repo

ProductionServer

Staging

Server

Deployment

Easy Git integrated deploys?

kirkhaines@MacBook-Pro ~/.ghq/github.com/wyhaines/demo-website (production) $ git push

Git Repo

ProductionServer

Staging

Server

Deployment

Easy Git integrated deploys?

On commit, deploy to N servers
Commits to different branches may be deployed to different servers
Easy to maintain implementation

Deployment

Easy Git integrated deploys?

Good all-git-reference:

https://www.digitalocean.com/community/tutorials/how-to-use-git-hooks-to-automate-development-and-deployment-tasks

Requires explicit specification of push target:

git remote add production demo@server_domain_or_IP:proj

Depends on your work environment knowing where to push.

Deployment

Easy Git integrated deploys?

Let's build it in Ruby!

Deployment

Serf is a nice tool

*but it's not Ruby

By Hashicorp

Lightweight
Distributed, gossip protocol daemon
Transmit events and data, trigger commands, get results
Nice tool for server orchestration
Not Ruby, but it is easy to interface with it using Ruby.

Deployment

Easy Membership Queries With Serf

$  serf members -rpc-auth="blahblahblah"
db-1-nyc1                        10.136.13.216:7946    alive  role=database
app-demo-1-nyc1                  10.81.218.50:7946     alive  role=app
app-demo-2-nyc1                  10.236.115.112:7946   alive  role=app
http-1-nyc1                      10.205.169.211:7946   alive  role=nginx

Deployment

Easy Command/Query Invocation With Serf

$ serf query -rpc-auth="blahblahblah" load-average
Query 'load-average' dispatched
Ack from 'db-1-nyc1'
Ack from 'app-1-nyc1'
Ack from 'http-1-nyc1'
Ack from 'app-2-nyc1'
Response from 'app-2-nyc1': 16:54:16,up,105,days,,20:48,,0,users,,load,average:,0.00,,0.00,,0.00
Response from 'app-1-nyc1': 16:54:16,up,108,days,,1:37,,1,user,,load,average:,0.00,,0.00,,0.00
Response from 'http-1-nyc1': 16:54:16,up,111,days,,1:39,,0,users,,load,average:,0.00,,0.00,,0.00
Response from 'db-1-nyc1': 16:54:16,up,105,days,,23:39,,1,user,,load,average:,0.00,,0.00,,0.00
Total Acks: 4
Total Responses: 4

Deployment

Easy Command/Query Invocation With Serf

$ serf query -rpc-auth="blahblahblah" list-handlers
Query 'list-handlers' dispatched
Ack from 'deploy-1-nyc1'
Ack from 'app-1-nyc1'
Ack from 'app-2-nyc1'
Ack from 'http-1-nyc1'
Response from 'app-1-nyc1': query: list-handlers
query: describe-handler
query: load-average
query: df
query: mpstat
query: ping
event: git-index-deploy
Response from 'db-1-nyc1': query: list-handlers
query: describe-handler
query: load-average
query: df
query: mpstat
query: ping
Response from 'app-2-nyc1': query: list-handlers
query: describe-handler
query: load-average
query: df
query: mpstat
query: ping
event: git-index-deploy
Response from 'http-1-nyc1': query: list-handlers
query: describe-handler
query: load-average
query: df
query: mpstat
query: ping
Total Acks: 4
Total Responses: 4

Deployment

Easy Command/Query Invocation With Serf

$ serf query -rpc-auth="blahblahblah" describe-handler git-index-deploy
Query 'describe-handler' dispatched
Ack from 'deploy-1-nyc1'
Ack from 'app-1-nyc1'
Ack from 'http-1-nyc1'
Ack from 'app-2-nyc1'
Response from 'app-1-nyc1': Expects a hash code in the payload which will
be queried using git-index. A 'git fetch --all && git pull' will be
executed on all matching repositories.
Response from 'app-2-nyc1': Expects a hash code in the payload which will
be queried using git-index. A 'git fetch --all && git pull' will be
executed on all matching repositories.
Total Acks: 4
Total Responses: 2

Deployment

Serf

Configuration

Is Simple

{
  "protocol": 5,
  "bind": "0.0.0.0",
  "advertise": "10.136.13.216",
  "rpc_addr": "0.0.0.0:7373",
  "rpc_auth": "blahblahblah",
  "enable_syslog": true,
  "log_level": "info",
  "replay_on_join": true,
  "snapshot_path": "/etc/serf/snapshot",
  "tags": {
    "role": "app"
  },
  "retry_join": [
    "db-1-nyc1",
    "app-2-nyc1",
    "http-1-nyc1"
  ],
  "event_handlers" : [
    "/usr/share/rvm/wrappers/ruby-2.5.1/serf-handler"
  ]
}

This is where we

hook Ruby into it

Deployment

Serf-Handler is a Framework and DSL for defining handlers for Serf queries and events

require 'serf/handler/events/load_average'
require 'serf/handler/events/df'
require 'serf/handler/events/mpstat'
require 'serf/handler/events/ping'
require 'serf/handler/events/git-index-deploy'

https://github.com/wyhaines/serf-handler

Wrote it on the airplane coming home from the Cookpad Bristol Office

Simple configuration - Just require something that uses the DSL

Several bundled handlers come with the gem

Deployment

Serf-Handler DSL is simple

require 'serf/handler' unless Object.const_defined?(:Serf) &&
  Serf.const_defined?(:Handler)

include Serf::Handler

describe "Return the 1-minute, 5-minute, and 15-minute load averages as a",
         "comma separated list of values."

on :query, 'load-average' do |event|
  `/usr/bin/uptime`.gsub(/^.*load\s+averages:\s+/,'').split.join(',').strip
end

load_average.rb

Deployment

git-index-deploy.rb

require 'serf/handler' unless Object.const_defined?(:Serf) && Serf.const_defined?(:Handler)
include Serf::Handler

describe "Expects a hash code in the payload which will be queried using",
         "git-index. A 'git fetch --all && git pull' will be executed on all",
         "matching repositories. Deployment hooks are available in order to",
         "execute arbitrary code during the deploy process. If any of the",
         "following files are found in the REPO root directory, they will be",
         "executed in the order described by their name.\n",
         ".serf-before-deploy\n",
         ".serf-after-deploy\n",
         ".serf-on-deploy-failure\n",
         ".serf-on-deploy-success\n"

on :event, 'git-index-deploy' do |event|
  user = `whoami` # Serf's executable environments are stripped of even basic information like HOME
  dir = `eval echo "~#{user}"`.strip
  `git-index -d #{dir}/.git-index.db -q #{event.payload}`.split(/\n/).each do |match|
    hash,data = match.split(/:\s+/,2)
    path,url = data.split(/\|/,2)

    ENV['SERF_DEPLOY_PAYLOAD'] = event.payload
    ENV['SERF_DEPLOY_HASH'] = hash
    ENV['SERF_DEPLOY_PATH'] = path
    ENV['SERF_DEPLOY_URL'] = url

    success = Dir.chdir(path)
    break unless success

    if FileTest.exist?(File.join(path, ".serf-before-deploy"))
      system(File.join(path, ".serf-before-deploy"))
    end

    success = system("git fetch --all && git pull")

    if success && FileTest.exist?(File.join(path, ".serf-on-deploy-success"))
      system(File.join(path, ".serf-on-deploy-success"))
    elsif !success && FileTest.exist?(File.join(path, ".serf-on-deploy-failure"))
      system(File.join(path, ".serf-on-deploy-failure"))
    end

    if FileTest.exist?(File.join(path, ".serf-after-deploy"))
      system(File.join(path, ".serf-after-deploy"))
    end
  end
end

Deployment

Oh yeah! git-index

https://github.com/wyhaines/git-index

Simple tool to make/maintain a database of git repositories

Calculates a "fingerprint" using the combination of the hashes of the first two commits in the repo -- it's enough to be reliably unique.

Deployment

Combine these with a git hook or github/gitlab web hook, and et voila! Ruby powered git based deploys.

kirkhaines@MacBook-Pro ~/.ghq/github.com/wyhaines/demo-website (production) $ git push

Git Repo

ProductionServer

Staging

Server

Configuration Management

This doesn't need much comment. Chef and Itamae are both Ruby based and capable.

https://github.com/itamae-kitchen/itamae

https://docs.chef.io/ruby.html

Log Management

I still think Analogger is pretty sweet if you just need something fast and reliable to get all of your logs into one place.

https://github.com/wyhaines/analogger

Log Management

Fluentd is Ruby and it's a power, all encompassing log management solution for your whole stack.

https://www.fluentd.org/

Other Stuff?

A Good Example of Ruby Power to Fill Niches

A tool to keep a folder or folders synchronized between multiple discrete systems, in a few hundred lines of Ruby.

https://github.com/sourcerer-io/rdfs

https://blog.sourcerer.io/a-distributed-file-sync-in-ruby-dbcf63a7cdf8

Bastion Host/Logged SSH

Bolwerk (mostly vapor-ware right now)

At EngineYard I wrote essentially an SSH proxy with full stream logging and 2-factor authentication, implemented in Ruby

Applying lessons learned to reimplement a much improved version
Fully searchable full stream logging of SSH sessions
Transparent and flexible
All Ruby, pluggable, and easily extensible

Still a private project, but hopefully it'll land on Github soon

Wrapping Up

This chain of thought was inspired by a couple real-world, mostly Ruby stacks that have been in production with few changes for 7+ years.

Swiftiply
IOWA
Analogger
ROMA
MySQL
Chef (solo)
Serf-Handler + Git-Index (+ Serf)

em-proxy
originally Mongrel, and now Puma, with Rails
Analogger
MySQL
Chef (solo)
Serf-Handler + Git-Index (+ Serf)

Wrapping Up

With some work, one could conceivably fill all the niches with Ruby:

em-proxy based load balancer
Shellac based static asset caching
Your favorite framework + app container
Fluentd or Analogger logging aggregation
ROMA key/value store
Kirk's Crazy Gossiping Distributed SQLite Server
Chef or Itamae
Serf-Handler + Git-Index (+ Serf)
Bolwerk for your bastion server/access control

Would You Want To?

Performance of the Ruby implementations can be completely reasonable
Ruby solutions are often less feature rich than the non-ruby options, but they are also more targeted at the key use-case, and are often very extensible for your exact needs.
Using them can make the architecture simpler to maintain (I never switched off Swiftiply and Analogger because nothing with comparable capability was nearly so easy to set up or configure for my needs at the time)

Why Might This Be Crazy?

You need every nanosecond of performance
You have very complex requirements that can be handled with an off-the-shelf component
Security risks -- more eyes on code mean finding vulnerabilities is more likely, but getting them fixed is also more likely
There should be a valid reason for not using a perfectly serviceable tool like NGINX -- do it in Ruby if you are also improving some aspect of the use case, for you.

Questions?

kirk-haines@cookpad.com / wyhaines@gmail.com / @wyhaines everywhere

It's Rubies All The Way Down - Paris.rb 2018

By wyhaines

It's Rubies All The Way Down - Paris.rb 2018

Paris.rb 2018 presentation on using Ruby for all of the layers in a full stack web app.