RethinkDB @ Sydney Node Ninjas

Transcript

1. RethinkDB Josh Hunt Developer @ Mi9
2. What is RethinkDB?
3. RethinkDB is… Open Source Database for the realtime web Schemaless ‘JSON’ document store Easy to develop, easy to deploy
4. RethinkDB is MongoDB that doesn't suck
5. Realtime Changefeeds Subscribe to any query and receive notification when data changes No need to poll for updates Eliminates infra and plumbing code
6. Easy development Modern, native query language in Javascript/Python/Ruby/Go/whatever Query features like join, map, reduce Web UI for testing queries (with docs!)
7. Easy deployment Scale with web UI for hassle-free sharding and replication Hosted options with Compose.io Support contracts available
8. Demo
9. Rethink(ing) Queries
10. ReQL 101 Native to your programming language by chaining functions Secure - injection attacks are minimised Queries are executed AND distributed by the server
11. Sample queries r.table('shows') .get('e346caa5...') r.table('actors') .pluck('lastName') .distinct().count()
12. More sample queries r.table('actors') .filter(r.row('age').gt(20)) r.table('characters') .filter({species: 'hobbit'}) .update({species: 'halfling'})
13. Demo
14. (Secondary) Indexes Indexes makes queries faster RethinkDB has auto GUID primary index Can have multiple secondary indexes, using any field, or multiple fields with compound indexes
15. Compound indexes r.table('cast').indexCreate('fullName', [r.row('firstName'), r.row('lastName')] )
16. Compound indexes r.table('cast').indexCreate('fullName', [r.row('firstName'), r.row('lastName')] ) r.table('cast').getAll( ['Josh', 'Hunt'], {index: 'fullName'} )
17. More ReQL Store (sub)queries into variables Location aware: query on geospatial data Accessing external APIs
18. Store subexpressions in variables to reuse or for subqueries expired = r.row('expiryDate').lt(r.row()) r.table('episodes') .filter(expired) .delete()
19. Store subexpressions in variables to remove boilerplate // models/Shows.js module.exports = r.table('shows') // routes/shows.js Shows = require('../models/Shows') Shows.get(req.params.showId)
20. Adding geospatial data r.table('cities').insert([ {name: 'Sydney', location: r.point(-33.865, 151.209)}, {name: 'Melbourne', location: r.point(-37.813, 144.963)} ])
21. Querying geospatial data home = r.point(-33.42, 149.57) r.table('cities') .getNearest(home, {index: 'location'}) r.table('cities') .get(1)('location') .distance(r.table(‘cities').get(2)('location'))
22. Accessing external APIs r.http('https://api.github.com/repos/joshhunt/uber') r.table('repos') .insert( r.http('https://api.github.com/repos/joshhunt/uber') .pluck('name', 'ssh_url', 'language', 'description', 'watchers_count') )
23. Realtime with Changefeeds
24. Realtime changefeeds Subscribe to change notifications on a database query Receive old and new value Works great with Javascript because its async
25. Get notified of every change to the show table r.table('shows') .changes() .run((update) => { update.each(console.log) })
26. Change for new document { old_val: null new_val: {name: 'Bilbo Baggins'} }
27. Change for updated document { old_val: {name: 'Gandalf the Grey'} new_val: {name: 'Gandalf the White'} }
28. Change for deleted document { old_val: {name: 'Saruman'} new_val: null }
29. Get notified when the top shows (by streams) changes r.table('shows') .orderBy({index: r.desc('streams')}) .limit(5) .changes()
30. Supported queries Subscribe to changes to get, between, filter, map, min, max, orderBy, limit
31. Use cases Anything realtime - chat, scores, etc To avoid making DB requests on every request Decouple and send analytics
32. Using Rethink with Node.js
33. Official driver r = require('rethinkdb'); r.connect() .then((conn) => { return r.table('show') .insert({name: 'The Block'}) .run() .finally( => { conn.close() }) }) .then((output) => { console.log(output); })
34. RethinkDB Dash Alternate driver with ‘advanced features’ Connection pooling - don’t worry about conn.close() Cursors are coerced to arrays by default
35. r.connect() .then((conn) => { return r.table('actors') .filter(r.row('age').gt(20)) .run() .finally( => { conn.close() }) }) .then((cursor) => { return cursor.toArray(); }) .then((result) => { assert(Array.isArray(result)); }) r = require('rethinkdbdash')(); r.table('actors') .filter(r.row('age').gt(20)) .run() .then((result) => { assert(Array.isArray(result)); }) Official driver vs rethinkdbdash
36. Thinky ORM Very light models for RethinkDB Handles creating indexes for you Automatically join tables (based on model definition)
37. Creating Thinky models Show = thinky.createModel('Show', { id: type.string(), title: type.string(), drm: type.boolean() }) Episode = thinky.createModel('Episode', { id: type.string(), title: type.string().min(2), description: type.string() }) Episode.belongsTo(Show, 'show', 'showId', 'id');
38. Creating documents with Thinky models show = new Show({title: 'The Block', drm: false}); episode = new Episode({title: 'Episode 455', description: ‘...'}); episode.show = show; episode.saveAll().then((savedEpisode) => { console.log(savedEpisode.id); })
39. Retrieving and joining with Thinky models Episode.get(req.params.episodeId) .getJoin().run() .then((episode) => { console.log(episode); assert(episode.show.title); })
40. Resources rethinkdb.com - Indepth API/query documentation - FAQ (rethinkdb vs mongodb) - Stability Report - Limitations of RethinkDB
41. Questions?