AP4R on RubyKaigi2007 (English only)

RubyKaigi 2007 AP4R Kiwamu Kato & Shun’ichi Shinohara Future Architect, Inc. 1

• Introduction • Demo • Real world examples • Technical topics 2

Introduction 3

Self Introduction 4

Kiwamu Kato • Majored in Civil Engineering • Has Enhanced and maintained messaging middleware in company 5

Kiwamu Kato • Started Ruby since last year • Leader of the AP4R team • http://d.hatena.ne.jp/kiwamu/ 6

shino • Programmer, I love coding ! • The language of the year is C or Haskell 7

shino • Last year, made a debut to the OSS world • http://d.hatena.ne.jp/ita-wasa/ 8

What is AP4R ? 9

Lightweight Messaging 10

What is AP4R ? • Asynchronous Processing for Ruby • Loose coupling by messaging 11

What can we do w/ AP4R ? • Quicker response to users • Load distribution 12

Press release 2006/09/05 http://itpro.nikkeibp.co.jp/article/NEWS/20060905/247218/ 13

Key points are .. 14

Lightweight and Robust 15

When is it useful ? 16

Quicker response to users 17

If NO speedy response is needed, execute it later

Before Client Server A B C D ... 19

After Client Server Messaging Server A B 20

After Client Server Messaging Server A B C D ... 21

Useful cases • Logging • Sending mail • Creating heavy summary data • Collaboration with other systems 22

Moreover, load distribution 23

Easy to scale out Client Server Messaging Server 24

Easy to scale out Client Server Messaging Servers 25

Only good things ? 26

Sounds easy ? 27

(Maybe) No 28

If message deliveries are NOT guaranteed,... 29

it may lead to message lost and message duplication 30

In other words... 31

•You can’t receive the goods despite payment ! • Double withdrawals ! 32

Messages should be delivered in a reliable way, 33

No matter what happens • Database trouble • Network trouble • Server down • Busy and timeout • ... etc 34

In Future Architect ... 36

We use messaging a lot • Developed own messaging library • Named “RtFA” 37

We use messaging a lot • Pure Java • Its own protocol, API (≠ JMS) • Time-proven on various systems 38

One of illustrative cases Mission critical system in transportation business http://japan.internet.com/linuxtoday/20061228/5.html 39

PJ summary • Over 100 million package data per day • Load distribution and parallel processing on 8 nodes of Oracle 10g RAC 40

PJ summary • Approx 100 servers • Used “RtFA”, an in-house middleware 41

Messaging is important

43

Lightweight Messaging 44

http://www.pragmaticprogrammer.com/titles/fr_j2r/ http://www.oreilly.co.jp/books/9784873113203/ 45

From RtFA to AP4R • Based on implementation/experiences with Java, kept good parts, improved bad parts • Focus on ease of use API, conﬁguration 46

Demo 48

Outline • Shopping store application • Order and payment 49

Shopping store app. Client Rails Order . Payment 50

Loose coupling AP4R Client Rails Rails × 3 Order 51

Loose coupling AP4R Client Rails Rails × 3 Payment Order 52

Loose coupling AP4R Client Rails Rails × 3 Payment Order Sleep 1 53

Outline • Use mongrel cluster • Stress by ab • Monitor queue retaining status 54

Real world examples 55

Two examples • Work With Rails • Our internal project 56

Working With Rails http://workingwithrails.com/ 57

WWR • is who’s who for Rails developers • listed 7,000 people from 104 countries 58

59

WWR • aggregates feeds from user’s blog • has scaling problem in fetching them slow/stale 60

WWR solution • Queue Feeds • Fetch async’ly \"Getting Distributed with Ruby on Rails\" slide #44 (from slideshare) 61

WWR solution • Able to scale • Flexible to feed types 62

Internal project 63

Brieﬁng • Work sheet management app. newly-building in Ruby • Labor cost accounting app. existing in Java 64

Requirements • Quick and rich UI • Replicate data between Java and Ruby 65

With AP4R • Separate loads from UI • Invoke Java from Ruby async’ly 66

Separate loads from UI Client Server Messaging Server 67

Separate loads from UI Client Server Messaging Server Create summary data, Send mails, etc. 68

Async’ly invoke Java Client Server Messaging Server 69

Async’ly invoke Java Client Server Messaging Server data replication, etc. 69

Utilize Async! when • Needless proc. for responce data • Disjoined transactions are allowable • External calls (often slow, unstable) 70

Technical topics 71

Two topics here • API to put messages and process ﬂow • Stored and Forward 72

API to put messages and process ﬂow 73

ap4r.async_to({specify next}, {request data} [,{more opts}]) There’s also block style c.f. RDoc: http://ap4r.rubyforge.org/doc/ 74

Class ShopController < ApplicationController def order # synchronous side ... ap4r.async_to({:action => ‘payment’}, {:id => 1}) redirect_to ... end def payment # asynchronous side id = params[:id] ... render :text => “true” end end 75

Process ﬂow 76

User Apache Rails AP4R 77

User Apache Rails AP4R order message put 78

User Apache Rails AP4R dispatch 79

User Apache Rails AP4R payment 80

Able to separate sync/async servers 81

User Apache Rails AP4R 82

Architecture AP4R HTTP AP4R DRB druby DRB reliable-msg SOAP XML -RPC AP4R MySQL mongrel HTTP 83

Thanks to DRb 4% 10% reliable-msg 20% mongrel 66% rails

Stored And Forward 85

Stored ? Forward ? 86

at-least-once between Producer and Channel 87

Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions by Gregor Hohpe,Bobby Woolf Guaranteed Delivery [122] 88

Typical ﬂow to create async. messages 89

start end 90

start CRUD end 90

start CRUD commit end 90

start CRUD commit message put / commit end 90

start CRUD commit message put / commit end data 90

start CRUD commit message put / commit end data messages 90

Ensure (some) Atomicness of updating database and message creation 91

On updating database • Error occurs, • Any following messages must NOT be queued 92

On updating database • Everything succeeded, • All following messages must be queued 93

☺ Relief 94

Ap4r::Client#transaction Class ShopController < ApplicationController def order # synchronous side ap4r.transaction do ... # CRUD on database ap4r.async_to ... end redirect_to ... end end 96

Process ﬂow changes in queueing sequence 97

Behind ap4r.transaction ap4r.transaction do ... # CRUD on database ap4r.async_to(...) end 98

Behind ap4r.transaction ap4r.transaction do ... # CRUD on database Insert into SAF table ap4r.async_to(...) end 98

Behind ap4r.transaction ap4r.transaction do ... # CRUD on database Insert into SAF table ap4r.async_to(...) end Commit database 98

Behind ap4r.transaction ap4r.transaction do ... # CRUD on database Insert into SAF table ap4r.async_to(...) end Commit database Queue messages 98

Behind ap4r.transaction ap4r.transaction do ... # CRUD on database Insert into SAF table ap4r.async_to(...) Store end Commit database Queue messages 98

Behind ap4r.transaction ap4r.transaction do ... # CRUD on database Insert into SAF table ap4r.async_to(...) Store end Commit database Queue messages Forward 98

Sequence in detail Without SAF 99

start CRUD commit message put / commit ☠ end data messages 101

start CRUD commit counterchange message put / commit end data messages 102

start CRUD message put / commit counterchange commit end data messages 103

start CRUD message put / commit commit end data messages 104

start CRUD message put / commit commit end data messages 105

start CRUD message put / commit commit ☠ end data messages 105

Better Safe than Sorry • Database trouble • Network trouble • Server down • busy and timeout • ... etc 106

☺ Embrace every exceptions ☠ 107

Sequence in detail With SAF 108

CRUD start SAF create commit message put / commit SAF update end data messages 109

CRUD start SAF create commit message put / commit SAF update ☺ end data messages 111

CRUD start SAF create commit message put / commit SAF update end data messages messages 113

CRUD start SAF create commit message put / commit SAF update ☺ end data messages messages 113

CRUD start SAF create commit message put / commit Recoverable SAF update ☺ end data messages messages 113

CRUD start SAF create commit message put / commit SAF update end data messages messages 115

CRUD start SAF create commit message put / commit Duplicated SAF update ☺ end data messages messages 115

Ensure (some) Atomicness of data and messages 116

at-least-once between Producer and Channel 117

Summary 118

• Messaging with simple API, simple conﬁguration. • Seamless collaboration with Rails 119

• Automatic invocation of async proc. • Guaranteed delivery by SAF 120

Future Plans 122

Smooth operation ver.0.3.x ☑ Daemonize ☑ URL-rewrite ﬁlter □ DLQ / SAF recovery □ Protocols: Stomp, HTTP 123

Monitoring ver.0.4.x □ Coordinate with Cacti, Nagios, etc. □ Many AP4R processes □ Interactive management tool 124

Step to large scale ver.0.5.x □ Dynamic conﬁguration □ Automatic recovery □ Long running 125

Others □ Security □ Application testing support □ Blocking queues 126

AP4R@RubyForge • wiki: http://ap4r.rubyforge.org/wiki/wiki.pl?HomePage • source: svn co svn://rubyforge.org/var/svn/ap4r Your patches are welcome! Thank you. 127

• Future Architect logo belong to Future Architect, Inc. Japan. All rights reserved. • Rails logo are trademarks of David Heinemeier Hansson. All rights reserved. • The Ruby logo is copyright c 2006, Yukihiro Matsumoto. It is released under the terms of the Creative Commons Attribution-ShareAlike 2.5 License. 128

AP4R on RubyKaigi2007 (English only)

0 comments

Notes on slide 1

3 Favorites