Async and Non-blocking IO w/ JRuby
1 like3,885 views
The document discusses asynchronous and non-blocking I/O with JRuby. It explains that asynchronous operations are better than synchronous operations because they use fewer resources and allow for parallelism. It provides an example of building a JRuby application with the Ratpack framework that makes asynchronous HTTP requests to eBay's API in a non-blocking way using promises. It also discusses using RxJava and Hystrix with Ratpack to build a book management application that handles data and API requests asynchronously.
![SYNCHRONOUS EXAMPLE
results = terms.map do |item|
url = rest_url(item)
response = Net ::HTTP.get(url)
JSON.parse(response)["Item"]
end.flatten
render(results)](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-22-320.jpg)
![ASYNCHRONOUS EXAMPLE
results = []
terms.each do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url).then do |response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
end
Promise.value(results).then { |r| render(r) }](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-24-320.jpg)
![ASYNCHRONOUS EXAMPLE
results = []
terms.each do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url).then do |response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
end
Promise.value(results).then { |r| render(r) }
Promise](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-25-320.jpg)
![ASYNCHRONOUS EXAMPLE
results = []
terms.each do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url).then do |response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
end
Promise.value(results).then { |r| render(r) }](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-26-320.jpg)
![ASYNCHRONOUS EXAMPLE
results = []
terms.each do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url).then do |response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
end
Promise.value(results).then { |r| render(r) }](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-27-320.jpg)
![promises = terms.map do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url)
end
batch = ParallelBatch.of(promises)
results = Collections.synchronized_list([])
operation = batch.for_each do |i, response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
operation.then { render(results) }](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-32-320.jpg)
![promises = terms.map do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url)
end
batch = ParallelBatch.of(promises)
results = Collections.synchronized_list([])
operation = batch.for_each do |i, response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
operation.then { render(results) }
Promise](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-33-320.jpg)
![promises = terms.map do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url)
end
batch = ParallelBatch.of(promises)
results = Collections.synchronized_list([])
operation = batch.for_each do |i, response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
operation.then { render(results) }](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-34-320.jpg)
![promises = terms.map do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url)
end
batch = ParallelBatch.of(promises)
results = Collections.synchronized_list([])
operation = batch.for_each do |i, response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
operation.then { render(results) }](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-35-320.jpg)
![promises = terms.map do |item|
url = rest_url(item)
http_client = ctx.get(HttpClient.java_class)
http_client.get(url)
end
batch = ParallelBatch.of(promises)
results = Collections.synchronized_list([])
operation = batch.for_each do |i, response|
body = response.get_body.get_text
results << JSON.parse(body)["Item"]
end
operation.then { render(results) }](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-36-320.jpg)
![RUN THE APP
$ bundle exec ruby lib/server.rb
[main] INFO ratpack.server.RatpackServer - Starting server ...
[main] INFO ratpack.server.RatpackServer - Building registry ...
[main] INFO ratpack.server.RatpackServer - Ratpack started ...](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-46-320.jpg)
![lib/book_service.rb
class BookService
def initialize
@db = BookDbCommands.new
@isbn_db = IsbnDbCommands.new
end
def all(ctx)
@db.all.flat_map do |row|
@isbn_db.get_book(ctx, row[:isbn]).map do |json|
row.merge(JSON.parse(json))
end
end.to_list
end](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-60-320.jpg)
![lib/book_service.rb
class BookService
def initialize
@db = BookDbCommands.new
@isbn_db = IsbnDbCommands.new
end
def all(ctx)
@db.all.flat_map do |row|
@isbn_db.get_book(ctx, row[:isbn]).map do |json|
row.merge(JSON.parse(json))
end
end.to_list
end
Observable](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-61-320.jpg)
![lib/book_service.rb
class BookService
def initialize
@db = BookDbCommands.new
@isbn_db = IsbnDbCommands.new
end
def all(ctx)
@db.all.flat_map do |row|
@isbn_db.get_book(ctx, row[:isbn]).map do |json|
row.merge(JSON.parse(json))
end
end.to_list
end Observable](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-62-320.jpg)
![lib/book_service.rb
class BookService
def initialize
@db = BookDbCommands.new
@isbn_db = IsbnDbCommands.new
end
def all(ctx)
@db.all.flat_map do |row|
@isbn_db.get_book(ctx, row[:isbn]).map do |json|
row.merge(JSON.parse(json))
end
end.to_list
end
Observable](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-63-320.jpg)
![lib/book_service.rb
class BookService
def initialize
@db = BookDbCommands.new
@isbn_db = IsbnDbCommands.new
end
def all(ctx)
@db.all.flat_map do |row|
@isbn_db.get_book(ctx, row[:isbn]).map do |json|
row.merge(JSON.parse(json))
end
end.to_list
end
Observable](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-64-320.jpg)
![lib/book_service.rb
class BookService
def initialize
@db = BookDbCommands.new
@isbn_db = IsbnDbCommands.new
end
def all(ctx)
@db.all.flat_map do |row|
@isbn_db.get_book(ctx, row[:isbn]).map do |json|
row.merge(JSON.parse(json))
end
end.to_list
end
Observable](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-65-320.jpg)
![lib/book_db_commands.rb
class BookDbCommands
def all(ctx)
s = HystrixObservableCommand ::Setter.
with_group_key(GROUP_KEY).
and_command_key(HystrixCommandKey ::Factory.as_key("getAll"))
Class.new(HystrixObservableCommand) do
def construct
RxRatpack.observe_each(Blocking.get {
DB["select isbn, quantity, price from books order by isbn"].all
})
end
def get_cache_key
"db-bookdb-all"
end
end.new(s).to_observable
end](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-68-320.jpg)
![lib/book_db_commands.rb
class BookDbCommands
def all(ctx)
s = HystrixObservableCommand ::Setter.
with_group_key(GROUP_KEY).
and_command_key(HystrixCommandKey ::Factory.as_key("getAll"))
Class.new(HystrixObservableCommand) do
def construct
RxRatpack.observe_each(Blocking.get {
DB["select isbn, quantity, price from books order by isbn"].all
})
end
def get_cache_key
"db-bookdb-all"
end
end.new(s).to_observable
end](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-69-320.jpg)
![lib/book_db_commands.rb
class BookDbCommands
def all(ctx)
s = HystrixObservableCommand ::Setter.
with_group_key(GROUP_KEY).
and_command_key(HystrixCommandKey ::Factory.as_key("getAll"))
Class.new(HystrixObservableCommand) do
def construct
RxRatpack.observe_each(Blocking.get {
DB["select isbn, quantity, price from books order by isbn"].all
})
end
def get_cache_key
"db-bookdb-all"
end
end.new(s).to_observable
end](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-70-320.jpg)
![lib/book_db_commands.rb
class BookDbCommands
def all(ctx)
s = HystrixObservableCommand ::Setter.
with_group_key(GROUP_KEY).
and_command_key(HystrixCommandKey ::Factory.as_key("getAll"))
Class.new(HystrixObservableCommand) do
def construct
RxRatpack.observe_each(Blocking.get {
DB["select isbn, quantity, price from books order by isbn"].all
})
end
def get_cache_key
"db-bookdb-all"
end
end.new(s).to_observable
end](https://image.slidesharecdn.com/rubykaigi2017-dark-170919072711/85/Async-and-Non-blocking-IO-w-JRuby-71-320.jpg)
![[245] presto 내부구조 파헤치기](https://cdn.slidesharecdn.com/ss_thumbnails/245presto-150915054242-lva1-app6891-thumbnail.jpg?width=560&fit=bounds)
![[오픈소스컨설팅] EFK Stack 소개와 설치 방법](https://cdn.slidesharecdn.com/ss_thumbnails/elasticstack-210712042246-thumbnail.jpg?width=560&fit=bounds)
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Async and Non-blocking IO w/ JRuby
- 1. ASYNCHRONOUS AND NON-BLOCKING I/O WITH JRUBY Joe Kutner
- 2. Joe Kutner @codefinger "Deploying with JRuby 9k" "The Healthy Programmer"
- 3. SYNCHRONOUS WAIT (BLOCKING) CLIENT SERVER DATABASE BLOCKING WAIT
- 4. BLOCKING IS BAD ▸ Each thread consumes resources ▸ Memory, Stack frames ▸ OS context switching ▸ GC has to walk the stack frames ▸ More $$$
- 5. ASYCHRONOUS WAIT (NON-BLOCKING) CLIENT SERVER DATABASE ASYNC WAIT
- 6. MULTIPLE CLIENTS CLIENT CLIENT SERVERCLIENT
- 7. MULTIPLE BACKING SERVICES CLIENT SERVER DATABASE REDIS
- 8. TEXT ASYNC IS GOOD ▸ Each request uses fewer resources ▸ Fewer threads ▸ Fewer servers ▸ Less $$$
- 9. TEXT WHO'S DOING ASYNC ▸ Apple ▸ Google ▸ Twitter ▸ Facebook ▸ eBay
- 14. Synchronous and Blocking (Sinatra) REQUEST REQUEST REQUEST REQUEST
- 15. REQUEST EVENT LOOP REQUEST REQUEST REQUEST Asynchronous and Non-blocking (Ratpack)
- 17. PROMISES promise = Blocking.get do # execution segment end promise.then do |result| # execution segment end
- 18. PROMISES promise = Blocking.get do # execution segment end promise.then do |result| # execution segment end EVENT LOOP
- 19. EBAY SEARCH A SYNTHETIC DEMO
- 22. SYNCHRONOUS EXAMPLE results = terms.map do |item| url = rest_url(item) response = Net ::HTTP.get(url) JSON.parse(response)["Item"] end.flatten render(results)
- 23. SYNCHRONOUS WAIT (BLOCKING) CLIENT SERVER EBAY BLOCKING WAIT
- 24. ASYNCHRONOUS EXAMPLE results = [] terms.each do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url).then do |response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end end Promise.value(results).then { |r| render(r) }
- 25. ASYNCHRONOUS EXAMPLE results = [] terms.each do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url).then do |response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end end Promise.value(results).then { |r| render(r) } Promise
- 26. ASYNCHRONOUS EXAMPLE results = [] terms.each do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url).then do |response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end end Promise.value(results).then { |r| render(r) }
- 27. ASYNCHRONOUS EXAMPLE results = [] terms.each do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url).then do |response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end end Promise.value(results).then { |r| render(r) }
- 28. SYNCHRONOUS WAIT (BLOCKING) CLIENT SERVER EBAY
- 29. ASYNCHRONOUS WAIT (NON-BLOCKING) CLIENT SERVER EBAY
- 31. ASYNC, PARALLEL EVENT LOOPEVENT LOOP Events Event handler Event emitters EVENT LOOPS
- 32. promises = terms.map do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url) end batch = ParallelBatch.of(promises) results = Collections.synchronized_list([]) operation = batch.for_each do |i, response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end operation.then { render(results) }
- 33. promises = terms.map do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url) end batch = ParallelBatch.of(promises) results = Collections.synchronized_list([]) operation = batch.for_each do |i, response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end operation.then { render(results) } Promise
- 34. promises = terms.map do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url) end batch = ParallelBatch.of(promises) results = Collections.synchronized_list([]) operation = batch.for_each do |i, response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end operation.then { render(results) }
- 35. promises = terms.map do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url) end batch = ParallelBatch.of(promises) results = Collections.synchronized_list([]) operation = batch.for_each do |i, response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end operation.then { render(results) }
- 36. promises = terms.map do |item| url = rest_url(item) http_client = ctx.get(HttpClient.java_class) http_client.get(url) end batch = ParallelBatch.of(promises) results = Collections.synchronized_list([]) operation = batch.for_each do |i, response| body = response.get_body.get_text results << JSON.parse(body)["Item"] end operation.then { render(results) }
- 37. ASYNCHRONOUS WAIT (NON-BLOCKING) CLIENT SERVER EBAY
- 38. ASYNCHRONOUS WAIT (NON-BLOCKING) AND PARALLEL CLIENT SERVER EBAY
- 40. HOW TO ASSEMBLE A JRUBY + RATPACK APP
- 42. Gemfile source 'https: //rubygems.org' ruby '2.3.3', engine: 'jruby', engine_version: '9.1.12.0' gem 'jbundler'
- 43. Jarfile jar 'io.ratpack:ratpack-core', '1.4.6' jar 'org.slf4j:slf4j-simple', '1.7.25'
- 44. INSTALL DEPENDENCIES $ bundle install $ jbundle install ... jbundler runtime classpath: ------------------------ .../ratpack-core-1.4.6.jar .../netty-common-4.1.6.Final.jar ... jbundle complete !
- 45. lib/server.rb require 'java' require 'bundler/setup' Bundler.require java_import 'ratpack.server.RatpackServer' RatpackServer.start do |b| b.handlers do |chain| chain.get("async") do |ctx| # async request handling end chain.get("sync") do |ctx| # sync request handling end end end
- 46. RUN THE APP $ bundle exec ruby lib/server.rb [main] INFO ratpack.server.RatpackServer - Starting server ... [main] INFO ratpack.server.RatpackServer - Building registry ... [main] INFO ratpack.server.RatpackServer - Ratpack started ...
- 47. FIND IT ON GITHUB https://github.com/jkutner/jruby-ratpack-async-demo
- 48. BOOKS EXAMPLE A REAL-WORLD DEMO
- 49. BOOKSTORE OR LIBRARY MANAGEMENT APP
- 51. RATPACK INTEGRATES WITH JAVA LIBRARIES ▸ RxJava ▸ compose & transform asynchronous operations ▸ Hystrix ▸ fault tolerance ▸ caching ▸ de-duping ▸ batching
- 53. MAP(F)
- 54. TIMEOUT( )
- 55. ZIP
- 56. Jarfile jar 'io.ratpack:ratpack-core', '1.4.6' jar 'io.ratpack:ratpack-rx', '1.4.6' jar 'io.ratpack:ratpack-hystrix', '1.4.6' jar 'org.slf4j:slf4j-simple', '1.7.25'
- 57. lib/server.rb RatpackServer.start do |b| book_service = BookService.new b.handlers do |chain| chain.get do |ctx| book_service.all(ctx).subscribe do |books| render_erb(ctx, "index.html.erb", binding) end end
- 58. lib/server.rb RatpackServer.start do |b| book_service = BookService.new b.handlers do |chain| chain.get do |ctx| book_service.all(ctx).subscribe do |books| render_erb(ctx, "index.html.erb", binding) end end Observable Subscription
- 59. lib/server.rb RatpackServer.start do |b| book_service = BookService.new b.handlers do |chain| chain.get do |ctx| book_service.all(ctx).subscribe do |books| render_erb(ctx, "index.html.erb", binding) end end
- 60. lib/book_service.rb class BookService def initialize @db = BookDbCommands.new @isbn_db = IsbnDbCommands.new end def all(ctx) @db.all.flat_map do |row| @isbn_db.get_book(ctx, row[:isbn]).map do |json| row.merge(JSON.parse(json)) end end.to_list end
- 61. lib/book_service.rb class BookService def initialize @db = BookDbCommands.new @isbn_db = IsbnDbCommands.new end def all(ctx) @db.all.flat_map do |row| @isbn_db.get_book(ctx, row[:isbn]).map do |json| row.merge(JSON.parse(json)) end end.to_list end Observable
- 62. lib/book_service.rb class BookService def initialize @db = BookDbCommands.new @isbn_db = IsbnDbCommands.new end def all(ctx) @db.all.flat_map do |row| @isbn_db.get_book(ctx, row[:isbn]).map do |json| row.merge(JSON.parse(json)) end end.to_list end Observable
- 63. lib/book_service.rb class BookService def initialize @db = BookDbCommands.new @isbn_db = IsbnDbCommands.new end def all(ctx) @db.all.flat_map do |row| @isbn_db.get_book(ctx, row[:isbn]).map do |json| row.merge(JSON.parse(json)) end end.to_list end Observable
- 64. lib/book_service.rb class BookService def initialize @db = BookDbCommands.new @isbn_db = IsbnDbCommands.new end def all(ctx) @db.all.flat_map do |row| @isbn_db.get_book(ctx, row[:isbn]).map do |json| row.merge(JSON.parse(json)) end end.to_list end Observable
- 65. lib/book_service.rb class BookService def initialize @db = BookDbCommands.new @isbn_db = IsbnDbCommands.new end def all(ctx) @db.all.flat_map do |row| @isbn_db.get_book(ctx, row[:isbn]).map do |json| row.merge(JSON.parse(json)) end end.to_list end Observable
- 66. OBSERVABLES ▸ all: Observable that will emit items ▸ flat_map: Applies a function to each item, and returns an Observable that emits items ▸ to_list: Returns an Observable that emits an Array of items ▸ subscribe: Returns a Subscription to the Observable
- 68. lib/book_db_commands.rb class BookDbCommands def all(ctx) s = HystrixObservableCommand ::Setter. with_group_key(GROUP_KEY). and_command_key(HystrixCommandKey ::Factory.as_key("getAll")) Class.new(HystrixObservableCommand) do def construct RxRatpack.observe_each(Blocking.get { DB["select isbn, quantity, price from books order by isbn"].all }) end def get_cache_key "db-bookdb-all" end end.new(s).to_observable end
- 69. lib/book_db_commands.rb class BookDbCommands def all(ctx) s = HystrixObservableCommand ::Setter. with_group_key(GROUP_KEY). and_command_key(HystrixCommandKey ::Factory.as_key("getAll")) Class.new(HystrixObservableCommand) do def construct RxRatpack.observe_each(Blocking.get { DB["select isbn, quantity, price from books order by isbn"].all }) end def get_cache_key "db-bookdb-all" end end.new(s).to_observable end
- 70. lib/book_db_commands.rb class BookDbCommands def all(ctx) s = HystrixObservableCommand ::Setter. with_group_key(GROUP_KEY). and_command_key(HystrixCommandKey ::Factory.as_key("getAll")) Class.new(HystrixObservableCommand) do def construct RxRatpack.observe_each(Blocking.get { DB["select isbn, quantity, price from books order by isbn"].all }) end def get_cache_key "db-bookdb-all" end end.new(s).to_observable end
- 71. lib/book_db_commands.rb class BookDbCommands def all(ctx) s = HystrixObservableCommand ::Setter. with_group_key(GROUP_KEY). and_command_key(HystrixCommandKey ::Factory.as_key("getAll")) Class.new(HystrixObservableCommand) do def construct RxRatpack.observe_each(Blocking.get { DB["select isbn, quantity, price from books order by isbn"].all }) end def get_cache_key "db-bookdb-all" end end.new(s).to_observable end
- 72. FIND IT ON GITHUB https://github.com/jkutner/jruby-ratpack-books-example
- 73. IN RUBY… WAYS TO DO ASYNC ▸ Netty (via Ratpack) ▸ Servlet 3.1 Async (via Warbler) ▸ Vert.x ▸ EventMachine
- 74. TEXT EVENTMACHINE ▸ Difficult to avoid callback hell ▸ Not integrated into your web framework
- 75. TEXT WHY NOT ASYC? ▸ Bottleneck is often the DB ▸ Async is hard ▸ Non-deterministic ▸ Callback hell ▸ Error handling/propagation
- 76. LINKS ▸ http://jruby.org ▸ https://ratpack.io ▸ https://netty.io ▸ http://reactivex.io ▸ https://github.com/jkutner/jruby-ratpack-async-demo ▸ https://github.com/jkutner/jruby-ratpack-books-example