cavia

[VERY MUCH A WORK IN PROGRESS]

Simple key value implementation on top of old fashioned sql.

Philosophy

Some stuff I like for storing my data

• A very simple engine with a minimal api (get, put, del, query) so it can be replaced with something more optimized if needed
• Old fashion storage engines that you can hire as a service and install locally
• options (sqlite, mysql, postgresql)
• Data model flexibility, no schemas
• Enforce querying on indexes, so they are always fast
• Separating indexes from the actual data, and dynamically generating them on put
• The ability to cheat on all of the above if you need it
• Transactions and aggregates

Obvious downsides

• No type checking, validation etc.
• Not very space efficient (index is data copy)
• Definitely not the fastest way to store data

Simple Example

models = 
	person: 
		kind: "person"
		indexes:
			age: {type: "int", getter: (data) -> data.age}

data =
	key: utils.uuid()
	kind: "person"
	name: "Koen Bok"
	age: 29

backend = new PostgresBackend "postgres://localhost/test"
store = new Store backend, [models.person]

store.create (err) ->
	
	# Store a person (upsert)
	store.put data, (err) ->
		
		# Get a person by key
		store.get "person", data.key (err, result) ->
			console.log result

		# Query persons older then 10 years
		store.query "person", {"name >": "10"}, (err, result) ->
			console.log result

Api

new Backend <"dsl">, <[models]>

store.create <"kind">, callback
store.get <"kind">, <"key", [keys]>, callback
store.put <"kind">, <{data}, [{data}]>, callback
store.del <"kind">, <"key", [keys]>, callback
store.query <"kind">, <{filters}>, callback

Run the tests

make test

Extras

REST API example using express. Deployable to Heroku.

Todo

• Make it work in the browser with websql database
• Add middleware system and implementations (caching, serializing, performance, logging, structured data validation, authentication)
• Add events action.pre|post
• Refactor transactions to be objects
• Refactor query pattern to something nicer (allowing querying on multiple indexes)

Inspiration

http://backchannel.org/blog/friendfeed-schemaless-mysql