Building Serverless Ruby Bots @ Ruby Conf 2018

Want to build a Bot without the hassle of provisioning and managing servers? Amazon’s got a service for that and it’s called AWS Lambda - it executes your code only when needed, scales automatically and you pay only for the compute time you consume.

There’s one problem with Lambda - it doesn’t support Ruby! 
Let’s checkout multiple options on how to build a Ruby Bot and package it into an executable which you can run on any machine without the need to actually have Ruby installed.

Transcript

1. BUILDING Serverless RUBY BOTS
3. NJUSKALO.HR
6. # Gemfile gem 'httparty' gem 'oga' gem 'actionmailer' gem 'rake' gem 'whenever'
8. Serverless
9. AWS LAMBDA
10. LANGUAGE SUPPORT JAVA, NODE.JS, PYTHON ...
11. 29 0CT 2015
12. 16 JAN 2018
13. NO RUBY? :(
14. TRAVELING Ruby MRuby JRuby
15. TRAVELING RUBY
16. MRUBY
17. JRUBY
19. SHRINK THE CODE BASE
20. GEMFILE gem 'httparty' gem 'actionmailer' gem 'whenever' gem 'rake' gem 'oga'
21. USE NET/HTTP gem 'httparty' gem 'actionmailer' gem 'whenever' gem 'rake' gem 'oga'
22. USE NET/HTTP gem 'httparty' gem 'actionmailer' gem 'whenever' gem 'rake' gem 'oga'
23. USE LAMBDA SCHEDULER gem 'httparty' gem 'actionmailer' gem 'whenever' gem 'rake' gem 'oga'
26. <li> ... <time datetime="2017-02-13T21:00:00+01:00">13.02.2017.</time> </li> <li> ... <time datetime="2017-02-13T21:08:12+01:00">13.02.2017.</time> </li> <li> ... <time datetime="2017-02-14T23:44:18+01:00">14.02.2017.</time> </li>
27. REGEX IT IS.
28. RUBY BOT CODE
29. # main.rb require 'net/http' require 'time' class NewApartments attr_reader :url def initialize(url) @url = url @last_scrapped_at = Time.now - 5 * 60 # 5 minutes ago. end def any? response_body .scan(/datetime\="(.*)" /) .any? { |published_at| Time.parse(published_at) > last_scrapped_at } end private def response_body Net::HTTP.get(URI(url)) end end
30. class MailgunEmailer def self.call Net::HTTP.post_form( URI("https://api:key-#{MAILGUN_API_KEY}@api.mailgun.net/v3/#{MAILGUN_DOMAIN}/messages"), from: "Apartment Bot <postmaster@#{MAILGUN_DOMAIN}>", to: RECIPIENT, subject: 'New Apartments found!', html: "Check new <a href='#{SEARCH_URL}'>apartments</a>" ) end end
31. SEARCH_URL = 'http://iapi.njuskalo.hr?sort=new&categoryId=10920&locationId=2619' MailgunEmailer.call if NewApartments.new(SEARCH_URL).any?
32. IMPLEMENTING THE BOT WITH Traveling Ruby PACKAGED MRI RUNTIMES
33. DOWNLOAD THE RUNTIMES OS X FOR OUR DEV MACHINE LINUX X86_64 COMPATIBLE BINARY FOR AWS LAMBDA
34. curl -O https://d6r77u77i8pq3.cloudfront.net/releases/traveling-ruby-20141215-2.1.5-linux-x86_64.tar.gz curl -O https://d6r77u77i8pq3.cloudfront.net/releases/traveling-ruby-20141215-2.1.5-osx.tar.gz
35. traveling-ruby-bot - ruby-linux-x86_64/ - ruby-os-x/
36. traveling-ruby-bot - ruby-linux-x86_64 - bin/ - ruby - ... - ... - ruby-os-x - bin/ - ruby - ... - ...
37. traveling-ruby-bot - ruby-linux-x86_64/ - ruby-os-x/ - main.rb
38. USUAL RUBY EXECUTION ruby main.rb
39. INVOKE WITH TRAVELING RUBY ruby-os-x/bin/ruby main.rb
40. UPLOADING THE BOT TO AWS Lambda
41. // lambda-function-wrapper.js var spawn = require('child_process').spawn; exports.handler = function(event, context) { var child = spawn('ruby-linux-x86_64/bin/ruby main.rb'); child.stdout.on('data', function (data) { console.log("stdout:\n"+data); }); child.stderr.on('data', function (data) { console.log("stderr:\n"+data); }); child.on('close', function (code) { context.done(); }); }
42. zip ruby-bot.zip ruby-linux-x86_64 main.rb lambda-function-wrapper.js
43. 1. CREATE A FUNCTION
44. 2. CREATE A TRIGGER
45. 3. CREATE A RULE FOR THE TRIGGER
46. 4. UPLOAD THE FUNCTION CODE
47. 5. SET A HANDLER
48. IMPLEMENTING THE BOT WITH mruby
49. TWO WAYS TO BUILD APPS WITH MRUBY: - DOWNLOAD MRUBY SOURCE DIRECTLY FROM GITHUB - MRUBY-CLI - PLATFORM FOR BUILDING NATIVE COMMAND LINE APPLICATIONS FOR LINUX, WINDOWS, AND OS X.
50. BUILDING DIRECTLY FROM MRUBY SOURCE
51. git clone https://github.com/mruby/mruby
52. mruby-bot - bin - build_config.rb - minirake
53. ./MINIRAKE
54. mruby-bot - bin/ - mruby - mirb - build_config.rb - minirake
55. > echo "print 'hello world'" >> hello_world.rb
56. INVOKE WITH MRUBY bin/mruby hello_world.rb
57. > bin/mruby main.rb main.rb:1: undefined method 'require' for main (NoMethodError)
58. # build_config.rb conf.gem github: 'iij/mruby-env' conf.gem github: 'mattn/mruby-curl' conf.gem github: 'mattn/mruby-onig-regexp'
59. ./MINIRAKE
60. EXECUTE THE CODE bin/mruby main.rb
61. CROSS COMPILATION
62. IMPLEMENTING THE BOT WITH JRUBY
63. AWS LAMBDA JRUBY
64. jruby-bot - lib/ - jruby.jar - src/ - main/ - resources/ - main.rb - gradlew
65. PASTE CODE mv main.rb src/main/resources/main.rb
66. BUILD THE PROJECT ./gradlew build
67. UPLOAD THE BOT CODE
68. METRICS & NUMBERS
69. CODE SIZE Traveling Ruby 6.7 MB mruby 945 kB JRuby 24 MB
70. MEMORY CONSUMPTION Traveling Ruby 25 MB mruby 40 MB JRuby 150 MB
71. EXECUTION TIME (COLD START) Traveling Ruby ~3900 ms mruby ~3900 ms JRuby ~25000 ms
72. COLDSTARTS
73. EXECUTION TIME (WARMED UP) Traveling Ruby ~3300 ms mruby ~3300 ms JRuby ~1200 ms
74. YMMV
75. AWS LAMBDA PRICING
76. AWS LAMBDA PRICING THE NUMBER OF REQUESTS (I.E. NUMBER OF TIMES OUR FUNCTION IS INVOKED) THE SUM OF DURATIONS OUR FUNCTIONS TOOK TO EXECUTE (EXPRESSED IN GB-SECONDS)
77. FREE TIER 1M REQUESTS & 400,000 GB-SECONDS PER MONTH
78. 1M TIMES PER MONTH ROUGLY EVERY 3 SECONDS
79. 400,000 GB-SECONDS / MONTH MEMORY SIZE * DURATION IN SECONDS
80. e.g. 128MB * 4s = 0.5GB-secons
81. IF WE RAN THE BOT EVERY MINUTE 20.000 GB-SECONDS
82. CHOOSING THE RIGHT Ruby FOR THE JOB
83. Traveling Ruby LOW MEMORY CONSUMPTION / WELL KNOWN ENVIRONMENT SUPPORT?
84. MRuby LOW MEMORY CONSUMPTION / LIGHTWEIGHT LIBRARY SUPPORT / CROSS COMPILATION
85. JRuby SIMPLE PACKAGING* / FAST EXECUTION HIGH MEMORY CONSUMPTION / JAVA ERRORS
86. Alternatives
87. RUBY Packer RUBY Snap
88. Azure FUNCTIONS Google Cloud FUNCTIONS
90. Lots of OPTIONS
91. Hacky OPTIONS
92. ..A MONTH AGO..
93. APACHE OpenWhisk
94. IBM Cloud Functions
95. IBM Cloud Functions
96. Inline editor
97. Serverless Framework SUPPORT
99. serverless create --template openwhisk-ruby --path ruby_bot
100. - ruby_bot - handler.rb - serverless.yml
101. # serverless.yml service: ruby_bot provider: name: openwhisk runtime: ruby functions: ruby_bot: handler: handler.main plugins: - serverless-openwhisk
102. serverless deploy
103. JETS SERVERLESS FRAMEWORK FOR RUBY
104. Jets.application.routes.draw do get 'posts', to: 'posts#index' end class PostsController < ApplicationController def index render json: { hello: 'world', action: 'index' } end end
105. FaastRuby.io
106. Conclusion
107. SERVERLESS-RUBY.ORG
109. DAMIR SVRTAN
112. tinyurl.com/netflix-ruby
113. DAMIR SVRTAN SENIOR SOFTWARE ENGINEER @ Netflix HIT ME UP @DamirSvrtan TINYURL.COM/NETFLIX-RUBY