MongoEngine - NoORM for NoSQL

The talk about MongoEngine presented on PyCon Russia 2013.

Transcript

1. MongoEngine NoORM for NoSQL Serge Matveenko github.com/lig PyCon Russia 2013
2. Quick MongoDB intro NoSQL document-oriented database • scalable (auto-sharding, replication) • high-performance (~104-105 queries/sec) • open source (db: AGPL, drivers: Apache)
3. RDBMS vs MongoDB RDBMS MongoDB data DB + Driver DB + PyMongo aggregation constraints Application validation cascade updates business logic Application
4. RDBMS vs MongoDB RDBMS MongoDB data DB + Driver DB + PyMongo aggregation constraints MongoEngine validation cascade updates business logic Application Application
5. MongoEngine class CharacterName(EmbeddedDocument): first = StringField() last = StringField() class Character(Document): name = EmbeddedDocumentField(CharacterName) rating = IntField() MongoDB { "_id" : ObjectId ("5125e0ee98764119e77d9b1f"), "_types" : ["Character"], "rating" : 42, "name" : {"_types" : ["CharacterName"], "last": "Connor", "_cls": "CharacterName", "first": "Sarah"}, "_cls": "Character" } How it looks
6. MongoEngine class CharacterName(EmbeddedDocument): first = StringField() last = StringField() class Character(Document): name = EmbeddedDocumentField(CharacterName) rating = IntField() MongoDB { "_id" : ObjectId ("5125e0ee98764119e77d9b1f"), "rating" : 42, "name" : {"last": "Connor", "_cls": "CharacterName", "first": "Sarah"}, "_cls": "Character" } How it looks (MongoEngine 0.8)
7. Simple db.character.find({'name.first': 'John'}) Character.objects(name__first='John') db.character.find({rating: {$gte: 42}}).limit(5) Character.objects(rating__gte=42)[:5] db.character.find({rating: {$exists: false}}) Character.objects(rating__exists=False) Querying with MongoEngine
8. Map/Reduce db.character.mapReduce(map_f, reduce_f, {out: 'mr_col'}); db.mr_col.find(); Character.objects.map_reduce(map_f, reduce_f, 'mr_col') Querying with MongoEngine
9. Creating db.character.save( {name: {first: 'John', last: 'Conor'}, rating: 42}) jc = Character( name=CharacterName(first='John', last='Conor'), rating=42) jc.save() Updating with MongoEngine
10. Atomic updates db.character.update( {name: {first: "John", last: "Conor"}}, {$set: {"name.last": "Connor"}}) Character.objects( name=CharacterName(first='John', last='Conor') ).update(set__name__last='Connor') Updating with MongoEngine
11. Under the hood MongoDB "C" BSON Module PyMongo MongoEngine JavaScript Console Binary data Python native types Declarative classes
12. Under the hood MongoDB "C" BSON Module PyMongo MongoEngine JavaScript Console Binary data Python native types Declarative classes
13. Performance
14. Out of the box • authentication backend • session engine • GridFSStorage Third party • stephrdev/django-mongoforms (Model Forms port) • wpjunior/django-mongotools (forms, generic views) • lig/django-registration-me (django-registration port) Django integration
15. Customizing things (added today. sorry:) • SequenceField(value_decorator=func) • StringField(regex=r'…') • URLField(verify_exists=True) • … • Inherit from standard Field classes • Write your own Field classes • Inherit from BaseDocument class, don't forget metaclass! • Any metamagic your like…
16. Questions? Serge Matveenko (github.com/lig) mongoengine.org www.mongodb.org Thanks to Ross Lawley (github.com/rozza) Elena Voronina :)