Scala DSLs: Dissecting (and reimplementing) Rogue

Just a few simple slides for a presentation at Kraków's Scala User Group. The rest of the session is live coding where we reimplement a tiny subset of Rogue, Foursquares MongoDB DSL.

Transcript

1. Konrad Malawski / @ktosopl GDG / PJUG / KSUG / SCKRK ScalaCamp 23.01.2012 Scala DSLs Dissecting Rogue Wednesday, December 26, 12
2. Wednesday, December 26, 12
3. Querying Mongo Wednesday, December 26, 12
4. Querying Mongo Wednesday, December 26, 12
5. Querying Mongo Wednesday, December 26, 12
6. QL = Plain JSON Querying Mongo Wednesday, December 26, 12
7. QL = Plain JSON JavaScript Console Querying Mongo Wednesday, December 26, 12
8. QL = Plain JSON JavaScript Console Java Driver Querying Mongo Wednesday, December 26, 12
9. QL = Plain JSON JavaScript Console Java Driver Casbah = Scala Driver Querying Mongo Wednesday, December 26, 12
10. QL = Plain JSON JavaScript Console Java Driver Casbah = Scala Driver ... used by Rogue Querying Mongo Wednesday, December 26, 12
11. Querying Mongo: JS Console API Wednesday, December 26, 12
12. Querying Mongo: JS db.inventory.find( {} ) Wednesday, December 26, 12
13. Querying Mongo: JS db.inventory.find( {} ) “find all” Wednesday, December 26, 12
14. Querying Mongo: JS db.inventory.find( { qty: { $gt: 20 } } ) Wednesday, December 26, 12
15. Querying Mongo: JS db.inventory.find( { qty: { $gt: 20 } } ) gt means >= Wednesday, December 26, 12
16. Querying Mongo: JS db.pople.find( { age: { $gte: 20 }, $or: [ { name: “Ken” }, { name: “Kenshiro” }, { city: “Tokyo” }, ... ] } ) Wednesday, December 26, 12
17. Querying Mongo: JS db.pople.find( { age: { $gte: 20 }, $or: [ { name: “Ken” }, { name: “Kenshiro” }, { city: “Tokyo” }, ... ] } ) $or may contain any clause Wednesday, December 26, 12
18. Querying Mongo: Java Java API (Morhpia) Wednesday, December 26, 12
19. Querying Mongo: Java ds.find(Employee.class).field("manager").equal(null).get(); Wednesday, December 26, 12
20. Querying Mongo: Java ds.find(Employee.class).field("manager").equal(null).get(); You call this typesafe!? Wednesday, December 26, 12
21. Mongo with Rogue Wednesday, December 26, 12
22. Rogue in Action import com.foursquare.rogue.Rogue._ Wednesday, December 26, 12
23. Rogue in Action Person where(_.age gte 18) limit(100) fetch() Wednesday, December 26, 12
24. Rogue in Action Person where(_.age gte 18) limit(100) fetch() Code Completion Code Completion Code Completion Code Completion Wednesday, December 26, 12
25. Rogue in Action Person where(_.age gte “Bazinga”) limit(100) fetch() Wednesday, December 26, 12
26. Rogue in Action Person where(_.age gte “Bazinga”) limit(100) fetch() Won’t compile - age is IntField Wednesday, December 26, 12
27. Rogue in Action Person where(_.age gte 18) limit(100) fetch() Wednesday, December 26, 12
28. Rogue in Action Person where(_.age gte 18) limit(100) fetch() Limit Wednesday, December 26, 12
29. Rogue in Action Person where(_.age gte 18) limit(100) foreach { p => println(”Name: ” + p.firstName) } Wednesday, December 26, 12
30. Rogue in Action Person where(_.age gte 18) limit(100) foreach { p => println(”Name: ” + p.firstName) } gte means >= Wednesday, December 26, 12
31. Rogue in Action Person or( _.where(_.name eqs "Ken"), _.where(_.name eqs "ken") _.whereOpt(Option("Kenshiro")(_.name eqs _)) ) get() Wednesday, December 26, 12
32. Rogue in Action Person or( _.where(_.name eqs "Ken"), _.where(_.name eqs "ken") _.whereOpt(Option("Kenshiro")(_.name eqs _)) ) get() eqs means Equals Wednesday, December 26, 12
33. Rogue in Action Person or( _.where(_.name eqs "Ken"), _.where(_.name eqs "ken") _.whereOpt(Option("Kenshiro")(_.name eqs _)) ) get() Get me one Person. eqs means Equals Wednesday, December 26, 12
34. Rogue in Action Person or( _.where(_.name eqs "Ken"), _.where(_.name eqs "ken") _.whereOpt(Option("Kenshiro")(_.name eqs _)) ) get() Get me one Person. eqs means Equals Issue #69: fix in my pull req Wednesday, December 26, 12
35. Live Hacking Wednesday, December 26, 12
36. Live Hacking Wednesday, December 26, 12
37. Live Hacking Wednesday, December 26, 12
38. Advanced Stuff. Live Hacking Wednesday, December 26, 12
39. Advanced Stuff. Fast. Live Hacking Wednesday, December 26, 12
40. Advanced Stuff. Fast. Ask Questions! Live Hacking Wednesday, December 26, 12
41. Wednesday, December 26, 12
42. def links = • Scala Lang http://www.scala-lang.org/ • Scala Koans http://www.scalakoans.org • Blog.Project13.pl - http://www.blog.project13.pl •MongoDB ref - docs.mongodb.org/manual/reference/operators/ • Foursquare Rogue - https://github.com/foursquare/rogue • Java Morphia - http://code.google.com/p/morphia/ • Kraków Scala UG - http://krakowscala.pl / http://scalacamp.pl Wednesday, December 26, 12
43. def links = • Scala Lang http://www.scala-lang.org/ • Scala Koans http://www.scalakoans.org • Blog.Project13.pl - http://www.blog.project13.pl •MongoDB ref - docs.mongodb.org/manual/reference/operators/ • Foursquare Rogue - https://github.com/foursquare/rogue • Java Morphia - http://code.google.com/p/morphia/ • Kraków Scala UG - http://krakowscala.pl / http://scalacamp.pl Mailing lists rock! Wednesday, December 26, 12
44. Konrad Malawski / @ktosopl GDG / PJUG / KSUG / SCKRK ScalaCamp 23.01.2012 Thanks! Dziękuję! ͋Γ͕ͱ͏ʂ Wednesday, December 26, 12
45. I love feedback! <3 Konrad Malawski / @ktosopl GDG / PJUG / KSUG / SCKRK ScalaCamp 23.01.2012 Thanks! Dziękuję! ͋Γ͕ͱ͏ʂ Wednesday, December 26, 12