Ruby 2.5: What's New and What's Cool

Miami Ruby Brigade
Monday, January 15, 2018

Transcript

1. Ruby 2.5 What's New and What's Cool Miami Ruby Brigade Monday, January 15, 2018
2. tl;dr • feature and performance update release • new features are cool • some stuff is faster • some stdlibs are now default gems • some other bits & bobs have changed
3. Topics • Intro • Features • Demos • Q&A
4. https://www.ruby-lang.org/en/news/2017/12/25/ruby-2-5-0-released/
5. Getting Ruby 2.5 • rbenv • Docker hub • Heroku • rvm
6. Running an App? Go for it (With adequate testing)
7. Maintaining a Library? Know it exists and test with it
8. do / rescue / end Exception handling in a block doesn't require begin
9. https://github.com/bkerley/mastodon/commit/589cdff
10. Object#yield_self Similar to #tap but it returns the result instead of the receiver
12. Hash#slice Grabs a sub-hash with the given keys
13. https://github.com/bkerley/tides_and_currents/commit/bbb8ab78
14. Hash#transform_keys • Returns a new hash with the keys mapped to something new
16. Struct.new keyword Struct#new supports keyword arguments now
18. Enumerable#any? #all? #none? #one? threequals Find if members in a collection threequal some pattern
21. Reverse backtraces • Quality of life • On a terminal, unless you change $stderr, the most recent call is at the bottom instead of a million screens up
23. Topics • Intro • Features • Demos • Q&A
24. Upgrading Mastodon I decided to make Mastodon work in Ruby 2.5
25. Mastodon • Twitter-like • Open-source • Federated • Independent nodes
26. Setup Steps From a new Mastodon checkout on v2.1.3, and after Development setup steps 1. Update README.md to note that it's a weird research project 2. Remove "< 2.5.0" constraint on Ruby version from Gemfile 3. bundle 4. Some deps also have "< 2.5.0" ruby constraint 5. bundle update
27. app/models/media_attachment.rb def populate_meta 
 meta = {} 
 
 file.queued_for_write.each do |style, file| 
 begin 
 geo = Paperclip::Geometry.from_file file 
 
 meta[style] = { 
 width: geo.width.to_i, 
 height: geo.height.to_i, 
 size: "#{geo.width.to_i}x#{geo.height.to_i}", 
 aspect: geo.width.to_f / geo.height.to_f, 
 } 
 rescue Paperclip::Errors::NotIdentifiedByImageMagickError 
 meta[style] = {} 
 end 
 end 
 meta 
 end
29. app/models/media_attachment.rb def populate_meta 
 meta = {} 
 
 file.queued_for_write.each do |style, file| 
 begin 
 geo = Paperclip::Geometry.from_file file 
 
 meta[style] = { 
 width: geo.width.to_i, 
 height: geo.height.to_i, 
 size: "#{geo.width.to_i}x#{geo.height.to_i}", 
 aspect: geo.width.to_f / geo.height.to_f, 
 } 
 # rescue Paperclip::Errors::NotIdentifiedByImageMagickError 
 # meta[style] = {} 
 end 
 end 
 
 meta 
 end
31. app/models/media_attachment.rb def populate_meta 
 meta = {} 
 
 file.queued_for_write.each do |style, file| 
 geo = Paperclip::Geometry.from_file file 
 
 meta[style] = { 
 width: geo.width.to_i, 
 height: geo.height.to_i, 
 size: "#{geo.width.to_i}x#{geo.height.to_i}", 
 aspect: geo.width.to_f / geo.height.to_f, 
 } 
 rescue Paperclip::Errors::NotIdentifiedByImageMagickError 
 meta[style] = {} 
 end 
 
 meta 
 end
33. https://github.com/bkerley/mastodon/commit/589cdff
34. tides_and_currents • Code for Miami project • Gets tides and currents data from NOAA • Quick and dirty ruby scripts
35. get_stations.rb field_names = %w{geoGroupName stationId lat lon} 
 
 # …
 
 out_json = doc['stationList'].map do |stn| # … 
 field_names.map do |fn| 
 stn[fn] 
 end 
 end.compact
37. get_stations.rb field_names = %w{geoGroupName stationId lat lon} 
 
 # …
 
 out_json = doc['stationList'].map do |stn| # … 
 stn.slice(*field_names).values
 end.compact
39. https://github.com/bkerley/tides_and_currents/commit/bbb8ab78
40. Topics • Intro • Features • Demos • Q&A
41. Thanks