Download as PDF, PPTX
![Clutch
• CouchDB library for Clojure
• (Javascript) view creation and querying
support:
(save-‐view "count" :number-‐of-‐players
{:map "function(d){for (var k in d.players) {emit(d.players[k],1);}}"
:reduce "function (keys, values) { return sum(values); }"})
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-19-320.jpg)
![Clutch: Clojure view
server
• Use Clojure to write view functions:
(save-‐view "count" :number-‐of-‐players
(with-‐clj-‐view-‐server
{:map (fn [doc] (map #(vector % 1) (:players doc)))
:reduce (fn [keys values _] (reduce + values))}))
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-24-320.jpg)
![Clutch: Clojure view
server
• Use Clojure to write view functions:
(save-‐view "count" :number-‐of-‐players
(with-‐clj-‐view-‐server
{:map (fn [doc] (map #(vector % 1) (:players doc)))
:reduce (fn [keys values _] (reduce + values))}))
• Better, but:
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-25-320.jpg)
![Clutch: Clojure view
server
• Use Clojure to write view functions:
(save-‐view "count" :number-‐of-‐players
(with-‐clj-‐view-‐server
{:map (fn [doc] (map #(vector % 1) (:players doc)))
:reduce (fn [keys values _] (reduce + values))}))
• Better, but:
• Increases operational complexity
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-26-320.jpg)
![Clutch: Clojure view
server
• Use Clojure to write view functions:
(save-‐view "count" :number-‐of-‐players
(with-‐clj-‐view-‐server
{:map (fn [doc] (map #(vector % 1) (:players doc)))
:reduce (fn [keys values _] (reduce + values))}))
• Better, but:
• Increases operational complexity
• Won’t work on hosted platforms, e.g. Cloudant
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-27-320.jpg)
![Language Mapping
Javascript
emit([doc.a, doc.b], doc.c);
Thankfully, you don’t need to do much if any
interop in views…
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-36-320.jpg)
![Language Mapping
Javascript
emit([doc.a, doc.b], doc.c);
ClojureScript
Thankfully, you don’t need to do much if any
interop in views…
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-37-320.jpg)
![Language Mapping
Javascript
emit([doc.a, doc.b], doc.c);
ClojureScript
(js/emit
Thankfully, you don’t need to do much if any
interop in views…
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-38-320.jpg)
![Language Mapping
Javascript
emit([doc.a, doc.b], doc.c);
ClojureScript
(js/emit
(array (aget doc “a”)
Thankfully, you don’t need to do much if any
interop in views…
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-39-320.jpg)
![Language Mapping
Javascript
emit([doc.a, doc.b], doc.c);
ClojureScript
(js/emit
(array (aget doc “a”)
(aget doc “b”))
Thankfully, you don’t need to do much if any
interop in views…
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-40-320.jpg)
![Language Mapping
Javascript
emit([doc.a, doc.b], doc.c);
ClojureScript
(js/emit
(array (aget doc “a”)
(aget doc “b”))
(aget doc “c”))
Thankfully, you don’t need to do much if any
interop in views…
Chas Emerick: Writing CouchDB Views using ClojureScript
Tuesday, October 11, 2011](https://image.slidesharecdn.com/couchdb-clojurescript-views-111010231612-phpapp02/85/Writing-CouchDB-Views-using-ClojureScript-41-320.jpg)
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Writing CouchDB Views using ClojureScript
- 1. Writing CouchDB Views using ClojureScript Chas Emerick @cemerick http://cemerick.com http://snowtide.com Tuesday, October 11, 2011
- 2. @cemerick Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 3. @cemerick Founded Snowtide in 2001 Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 4. @cemerick Founded Snowtide in 2001 Clojure full-time since 2008 Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 5. @cemerick Founded Snowtide in 2001 Clojure full-time since 2008 Contributor to Clojure language & libraries Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 6. @cemerick Founded Snowtide in 2001 Clojure full-time since 2008 Contributor to Clojure language & libraries CouchDB user since 2009? Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 7. @cemerick Founded Snowtide in 2001 Clojure full-time since 2008 Contributor to Clojure language & libraries CouchDB user since 2009? O’Reilly author Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 8. CouchDB in 1minute Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 9. CouchDB in 1minute • Document-oriented data store Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 10. CouchDB in 1minute • Document-oriented data store • (Primary) key => JSON object Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 11. CouchDB in 1minute • Document-oriented data store • (Primary) key => JSON object • HTTP API Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 12. CouchDB in 1minute • Document-oriented data store • (Primary) key => JSON object • HTTP API • Secondary indexes / queries provided by ‘views’ Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 13. CouchDB in 1minute • Document-oriented data store • (Primary) key => JSON object • HTTP API • Secondary indexes / queries provided by ‘views’ • viz. materialized views in SQL-land Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 14. CouchDB in 1minute • Document-oriented data store • (Primary) key => JSON object • HTTP API • Secondary indexes / queries provided by ‘views’ • viz. materialized views in SQL-land • Defined by Javascript functions applied within a flavour of map/reduce Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 15. CouchDB in 1minute • Document-oriented data store • (Primary) key => JSON object • HTTP API • Secondary indexes / queries provided by ‘views’ • viz. materialized views in SQL-land • Defined by Javascript functions applied within a flavour of map/reduce • Same mechanism used elsewhere (filters, validation, etc) Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 16. Clutch Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 17. Clutch • CouchDB library for Clojure Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 18. Clutch • CouchDB library for Clojure • (Javascript) view creation and querying support: Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 19. Clutch • CouchDB library for Clojure • (Javascript) view creation and querying support: (save-‐view "count" :number-‐of-‐players {:map "function(d){for (var k in d.players) {emit(d.players[k],1);}}" :reduce "function (keys, values) { return sum(values); }"}) Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 20. “Javascript sucks” Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 21. “Javascript sucks” Q.E.D. Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 22. Clutch: Clojure view server Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 23. Clutch: Clojure view server • Use Clojure to write view functions: Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 24. Clutch: Clojure view server • Use Clojure to write view functions: (save-‐view "count" :number-‐of-‐players (with-‐clj-‐view-‐server {:map (fn [doc] (map #(vector % 1) (:players doc))) :reduce (fn [keys values _] (reduce + values))})) Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 25. Clutch: Clojure view server • Use Clojure to write view functions: (save-‐view "count" :number-‐of-‐players (with-‐clj-‐view-‐server {:map (fn [doc] (map #(vector % 1) (:players doc))) :reduce (fn [keys values _] (reduce + values))})) • Better, but: Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 26. Clutch: Clojure view server • Use Clojure to write view functions: (save-‐view "count" :number-‐of-‐players (with-‐clj-‐view-‐server {:map (fn [doc] (map #(vector % 1) (:players doc))) :reduce (fn [keys values _] (reduce + values))})) • Better, but: • Increases operational complexity Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 27. Clutch: Clojure view server • Use Clojure to write view functions: (save-‐view "count" :number-‐of-‐players (with-‐clj-‐view-‐server {:map (fn [doc] (map #(vector % 1) (:players doc))) :reduce (fn [keys values _] (reduce + values))})) • Better, but: • Increases operational complexity • Won’t work on hosted platforms, e.g. Cloudant Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 28. ClojureScript Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 29. ClojureScript • Clojure : JVM :: ClojureScript : JavaScript Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 30. ClojureScript • Clojure : JVM :: ClojureScript : JavaScript • Ahead-of-time compilation (no eval) Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 31. ClojureScript • Clojure : JVM :: ClojureScript : JavaScript • Ahead-of-time compilation (no eval) • (Optionally) uses Google Closure’s optimizing compiler Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 32. ClojureScript • Clojure : JVM :: ClojureScript : JavaScript • Ahead-of-time compilation (no eval) • (Optionally) uses Google Closure’s optimizing compiler • Eliminate need for Clojure/Clutch view server & need to write views in JavaScript! Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 33. Demo Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 34. Language Mapping Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 35. Language Mapping Javascript Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 36. Language Mapping Javascript emit([doc.a, doc.b], doc.c); Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 37. Language Mapping Javascript emit([doc.a, doc.b], doc.c); ClojureScript Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 38. Language Mapping Javascript emit([doc.a, doc.b], doc.c); ClojureScript (js/emit Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 39. Language Mapping Javascript emit([doc.a, doc.b], doc.c); ClojureScript (js/emit (array (aget doc “a”) Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 40. Language Mapping Javascript emit([doc.a, doc.b], doc.c); ClojureScript (js/emit (array (aget doc “a”) (aget doc “b”)) Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 41. Language Mapping Javascript emit([doc.a, doc.b], doc.c); ClojureScript (js/emit (array (aget doc “a”) (aget doc “b”)) (aget doc “c”)) Thankfully, you don’t need to do much if any interop in views… Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 42. Current issues Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 43. Current issues • ClojureScript is not a library (yet!) Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 44. Current issues • ClojureScript is not a library (yet!) • Cannot be depended upon in Leiningen/ Maven Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 45. Current issues • ClojureScript is not a library (yet!) • Cannot be depended upon in Leiningen/ Maven • Cannot target / test against particular versions (there aren’t any) Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 46. Current issues • ClojureScript is not a library (yet!) • Cannot be depended upon in Leiningen/ Maven • Cannot target / test against particular versions (there aren’t any) • Incomplete optimization: lots of code generated to define the simplest view Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 47. Thank you! snipe book Chas Emerick @cemerick http://cemerick.com http://snowtide.com Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 48. Thank you! • CouchDB: http://couchdb.apache.org snipe book Chas Emerick @cemerick http://cemerick.com http://snowtide.com Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 49. Thank you! • CouchDB: http://couchdb.apache.org • Clutch: http://github.com/ashafa/clutch snipe book Chas Emerick @cemerick http://cemerick.com http://snowtide.com Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 50. Thank you! • CouchDB: http://couchdb.apache.org • Clutch: http://github.com/ashafa/clutch • ClojureScript: https://github.com/clojure/ clojurescript snipe book Chas Emerick @cemerick http://cemerick.com http://snowtide.com Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011
- 51. Thank you! • CouchDB: http://couchdb.apache.org • Clutch: http://github.com/ashafa/clutch • ClojureScript: https://github.com/clojure/ clojurescript • Clutch-ClojureScript: http://github.com/ cemerick/clutch-clojurescript snipe book Chas Emerick @cemerick http://cemerick.com http://snowtide.com Chas Emerick: Writing CouchDB Views using ClojureScript Tuesday, October 11, 2011