Two things I found effective when starting up a new web service

Tech Talk Tokyo #2 May 24th, 2016.
https://techtalktokyo.doorkeeper.jp/events/44690

Transcript

1. Two things I found effective when starting up a new web service Tech Talk Tokyo #2 May 24th, 2016. @necojackarc
2. Taka Software Engineer Twitter: @necojackarc GitHub: necojackarc Blog (JP): http://necojackarc.hatenablog.com/ Blog (EN): http://necojackarc.hateblo.jp/
3. Outline ◦ Introducing a new web service by PIXTA ◦ Sharing two effective methods which make systems more extensible: • Immutable Data Model with additional restrictions • Adding extra components to MVC frameworks, especially “Ruby on Rails”
4. 1. Introducing a new web service The name is “fotowa”. URL: https://fotowa.com/
5. About “fotowa” III. photo shoot & online delivery II. request IV. reward I. registration Matching service between those who want to have their photos taken and photographers
6. Development of “fotowa” ◦ We released the first version on February 29th, 2016. ◦ It took one and a half months. ◦ I needed to take care of a lot of changes because the requirements weren't fixed. ◦ I found some methods which were effective to deal with frequent changes.
7. 2. Extended Immutable Data Model
8. What is Immutable Data Model? ◦ One of the styles of data modeling ◦ In a word, forbidding updating database • Practically, it’s almost impossible to make an application without updating any data. • So, it’s okay to just try and exclude as much update as possible.
9. Benefits of Immutable Data Model ◦ Keeping your data model simple • Updating usually causes complexity. ◦ Making your design open to change • You can easily extend and modify the design. ◦ Making your database robust
10. Let’s apply additional restrictions!
11. Additional restrictions They improve your database much more! ◦ Never updating records (already adopted) ◦ Never deleting records ◦ No null columns ◦ No deleted flags The more restrictions you apply, the more improvements you (might be able to) get :)
12. 3. Adding extra components to Rails
13. Brief introduction of Ruby on Rails ◦ It’s a MVC framework. • It originally has three components that are models, controllers and views. ◦ Developers often suffer from “fat stuff”. • Since Rails has only three components, developers tend to put “all business logic” on controllers or models. It causes fat models or fat controllers.
14. “ You may be thinking: “But Rails makes it really hard to do OOP right!” from “7 Patterns to Refactor Fat ActiveRecord Models”
15. It’s not true. Adding extras solves these problems.
16. • Decorators • Errors • Forms • Lib • Observers • Parameters • Serializers • Services • Uploaders Components I actually added
17. It enables you to apply Single Responsibility Principle.
18. Conclusion ◦ Extended Immutable Data Model makes your database open to change. ◦ Adding extra components enables you to follow Single Responsibility Principle which makes your application open to change.
19. Changes are inevitable 　Let’s prepare for changes!
20. References ◦ イミュータブルデータモデル(入門編) • http://www.slideshare.net/kawasima/ss-40471672 ◦ SIerにおけるDBAのしごと • http://qiita.com/kawasima/items/7eafd8406866f9d6e91b ◦ 7 Patterns to Refactor Fat ActiveRecord Models • http://blog.codeclimate.com/blog/2012/10/17/7-ways-to-decomp ose-fat-activerecord-models/ ◦ 肥大化したActiveRecordモデルをリファクタリングする7つの方法(翻訳) • http://techracho.bpsinc.jp/hachi8833/2013_11_19/14738
21. THANKS!