Making Relational Cool Again

From the June 30th #BostonJS in the park

Transcript

1. Making Relational Cool Again
3. Tim Griesser Twitter: @tgriesser IRC: tgriesser IRC Room: #bookshelf
5. ...easily building fast, scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data- intensive real-time applications that run across distributed devices.
6. ... it’s really good for webapps!
10. What about relational?
12. Sequelize node-orm2 node-mysql node-pg node-sqlite3 node-mariasql JugglinDB
13. • Lack of separation between query builder & ORM layer • Lack of transaction support • “Build queries by hand” • Inconsistent APIs among core libs • “Jack Of All Trades” Existing RBDMS Abstractions:
14. • Still a relatively young ecosystem • Lots of examples with NoSQL • Touted as great for: streaming, realtime applications, with buffers and websockets... • Not so much for model heavy applications as you’d see in Rails, Django, Laravel, $insert_language_framework_here
15. ...oh well, guess I’ll stick to what I know
17. • Well written & architected PHP framework by Taylor Otwell • Makes working in PHP not terrible • Uses Symfony2’s Components • Contains a great Query Builder, Schema Builder & ORM (Eloquent)
18. • Models, Collections, Views, Events, Routing for webapps • Solid conventions for RESTful data syncing • Flexible, easily extended, concise codebase • Lightweight, doesn’t add features without a number of solid real world use cases • For the 90% use case
19. Hmm…
20. So if Backbone is a library with Models, Collections, and Events in Javascript ...and Laravel has a nice Schema Builder, Query Builder, and ORM in PHP
21. could we combine them?
22. Query builder Eloquent Promises Models, Collections, Events
26. Knex Query Builder • Use javascript statements to build SQL expressions
27. Knex Query Builder • Query support for: • joins, where, having, union, aggregates, insert, update, delete, group by, order by, etc. • knex.raw(sql, [bindings]) • Foundation of Bookshelf.js
28. Knex Query Builder • Supports arbitrarily complex queries, with proper raw & subquery interpolation
32. • Code to help create and edit the database structure • Maintains consistency between datatypes in different query dialects • Used in combination with migrations to keep database properly structured Knex Schema Builder
34. Migrations • Provides the ability to modify database structure in a consistent / versioned way • $ knex migrate:make migration-name • $ knex migrate:latest • $ knex migrate:rollback
35. Transactions
36. Transactions
37. Additional Features • Events API • “query” event • “row” event (coming soon) • Streams API • knex.query.stream(options) • knex.query.pipe(writableStream)
39. Bookshelf - ORM • Quick refresher: • Object-Relational-Mapper • Values in data-store (MySQL, PostgreSQL, SQLite3) mapped to javascript objects (models) or arrays of models (collections)
40. Bookshelf - ORM • Takes care of standard SQL queries for you, especially for common CRUD operations • model.fetch() • model.fetchAll() • model.save() • model.destroy()
41. Association Types • One-To-One • hasOne • belongsTo • One-To-Many • hasMany • Many-To-Many • belongsToMany
42. Association Types • One-To-One • hasOne • belongsTo • One-To-Many • hasMany • Many-To-Many • belongsToMany
43. Association Types • One-To-One • hasOne • belongsTo • One-To-Many • hasMany • Many-To-Many • belongsToMany
44. Polymorphic Associations • Mapping a single model to multiple model types • Picture for employees, for products
47. Eager Loading • Avoids the N+1 Query Problem • Find a user with all associated accounts and for each of those accounts find the associated documents
50. Eager Loading •Avoids the N+1 Query Problem •Find a user with all associated accounts and for each of those accounts find the associated documents, where the document status is published
51. Dynamically constrain relations
52. Eager Loading (.load())
53. “Tapping into” the query chain • Allows for adding additional query parameters dynamically to the model’s query
54. Callback Hell Source: http://callbackhell.com/
55. Promises • Promises aren’t about a better syntax than callbacks • Promises are about error handling and making async code feel synchronous (try / catch / finally) • https://github.com/petkaantonov/bluebird#what-are- promises-and-why-should-i-use-them
56. Promises
57. Knex.js Connection Pooling Query Builder Schema Builder Query Runner
58. Knex.js Connection Pooling Query Builder Schema Builder Query Runner Bookshelf.js Relations Base Model & Collection Query Mapper Lifecycle Events
59. Knex.js Connection Pooling Query Builder Schema Builder Query Runner Bookshelf.js Relations Base Model & Collection Query Mapper Lifecycle Events Active Record-ish Library Scopes Validations Automatic Schema Other Neat Helpers
61. In The Wild
62. Next Steps • Finish up events API for Knex • knex.introspect() / Auto-Migrations • Refactoring internals of Bookshelf.js for more configurable and cleaner relations
63. Next Steps • Dropping Backbone dependency for Bookshelf.js • Minor API changes to Bookshelf - .save(options) • Integration with Checkit.js • Better Examples
64. Thanks • Freenode IRC: #bookshelf • Twitter @tgriesser • http://knexjs.org • http://bookshelfjs.org