RAILS AS 
 AN SOA CLIENT Pete Hodgson | @ph1 | [email protected]

@ph1 rails DB DB rails app

@ph1 rails a service a service DB DB rails app

@ph1 rails a service a service a service a service DB DB rails app

@ph1 rails a service a service a service a service rails app

me me me Pete Hodgson Consultant at ThoughtWorks @ph1 blog.thepete.net

@ph1 ACT ONE INDEPENDENCE CO-DEPENDENCE and

@ph1 a service rails app a service

@ph1 SELECTION OF DEALS ARRAY OF ENTICING PRODUCT CATEGORIES

@ph1 rails app product service deals service

@ph1 rails app

@ph1 rails app product service deals service RED TEAM GREEN TEAM BLUE TEAM

@ph1 CONWAY’S LAW

@ph1 SYSTEM ARCHITECTURE HOW PEOPLE WORK TOGETHER AFFECTS

@ph1 HOW PEOPLE WORK TOGETHER AFFECTS SYSTEM ARCHITECTURE

@ph1 rails app product service deals service RED TEAM GREEN TEAM BLUE TEAM

@ph1 WHO’S BUG IS IT ANYWAY?

@ph1 rails app deals service product service

@ph1 fake service fake service rails BOUNDED INTEGRATION
 TESTS rails app

@ph1 IN PROCESS OUT-OF-PROCESS vcr webmock mimic moco stubby montebank

@ph1 deals service product service rails product service deals service ✓ ? ? rails app

@ph1 CONTRACT TESTS

@ph1 rails app product service deals service

@ph1 product service deals service rails app

@ph1 (or minitest, or whatever) plain old rspec pacto pact

END-TO-END TESTS UNIT TESTS BOUNDED INTEGRATION TESTS SERVICE A CONTRACT TESTS SERVICE B CONTRACT TESTS SERVICE D CONTRACT TESTS SERVICE C CONTRACT TESTS FUNCTIONAL TESTS

END-TO-END TESTS UNIT TESTS BOUNDED INTEGRATION TESTS SERVICE A CONTRACT TESTS SERVICE B CONTRACT TESTS SERVICE D CONTRACT TESTS SERVICE C CONTRACT TESTS FUNCTIONAL TESTS

@ph1 ACT TWO SERVICE GATEWAYS

@ph1 faraday

@ph1 rack

CACHING AUTHENTICATION HTTP SERVER COOKIES LOGGING rack

@ph1 use Rack::Sendfile use ActionDispatch::Static use Rack::Lock use # use Rack::Runtime use Rack::MethodOverride use ActionDispatch::RequestId use Rails::Rack::Logger use ActionDispatch::ShowExceptions use ActionDispatch::DebugExceptions use ActionDispatch::RemoteIp use ActionDispatch::Reloader use ActionDispatch::Callbacks use ActiveRecord::Migration::CheckPending use ActiveRecord::ConnectionAdapters::ConnectionManagement use ActiveRecord::QueryCache use ActionDispatch::Cookies use ActionDispatch::Session::CookieStore use ActionDispatch::Flash use ActionDispatch::ParamsParser use Rack::Head use Rack::ConditionalGet use Rack::ETag run MyApp::Application.routes

@ph1 CACHING AUTHENTICATION HTTP CLIENT SERIALIZATION faraday

@ph1 class BikeStationGateway STATIONS_PATH = '/stations/json' ! def initialize( base_url = 'http://bayareabikeshare.com' ) @conn = Faraday.new(:url => base_url ) do |faraday| faraday.use :instrumentation faraday.response :json faraday.request :encode_json faraday.response :follow_redirects faraday.response :logger faraday.adapter Faraday.default_adapter end end ! def stations response = @conn.get(STATIONS_PATH) # ... parse response.body into a list of stations end end

@ph1 class BikeStationGateway STATIONS_PATH = '/stations/json' ! def initialize( base_url = 'http://bayareabikeshare.com' ) @conn = Faraday.new(:url => base_url ) do |faraday| faraday.use :instrumentation faraday.response :json faraday.request :encode_json faraday.response :follow_redirects faraday.response :logger faraday.adapter Faraday.default_adapter end end ! def stations response = @conn.get(STATIONS_PATH) # ... parse response.body into a list of stations end end

@ph1 a service a service service gateways

@ph1 hexagonal 
 architecture

@ph1 CACHING AUTHENTICATION HTTP CLIENT SERIALIZATION

@ph1 { “JSON”: “parsing” } !

@ph1 { "meta": { "response-time": "141", "server": "http://foo.com", ... }, "product": { "uid": "151231511315083", "summary": { "title": "A Book Of Things", "shortDescription": “.....", ... }, "author": { "firstName": "Bob", "lastName": "Smith", ... }, ... } }

@ph1 hashie lazy_doc embedded_doc representable

@ph1 CACHING AUTHENTICATION HTTP CLIENT SERIALIZATION

@ph1 rails app product service pricing service

@ph1 cache the crap out of this! /prod-images/15123_front.png

@ph1 cache the crap out of this too! /products/15123.json

@ph1 CACHING AUTHENTICATION HTTP CLIENT SERIALIZATION

@ph1 CACHING AUTHENTICATION HTTP CLIENT SERIALIZATION

@ph1 class BikeStationGateway STATIONS_PATH = '/stations/json' ! def initialize( base_url = 'http://bayareabikeshare.com' ) @conn = Faraday.new(:url => base_url ) do |faraday| faraday.use :instrumentation faraday.response :json faraday.request :encode_json faraday.response :follow_redirects faraday.response :logger ! faraday.use FaradayMiddleware::RackCompatible, Rack::Cache::Context, :metastore => "file:#{cache_dir}/faraday/meta", :entitystore => “file:#{cache_dir}/faraday/body", :ignore_headers => %w[Set-Cookie X-Content-Digest] ! ! faraday.adapter Faraday.default_adapter end end end

@ph1 on the web
 OF the web

@ph1 EPILOGUE SOME
 PRINCIPLES

@ph1 CONWAY’S LAW

@ph1 DOMAIN DRIVEN DESIGN

@ph1 POSTEL’S LAW

@ph1 HEXAGONAL ARCHITECTURE

@ph1 EMBRACE
 THE WEB

THANKS! Pete Hodgson @ph1
 [email protected]

57 SLIDES => Pete Hodgson @ph1
 [email protected]