Path: | README.md |
Last Update: | Thu Jul 02 02:57:44 -0600 2009 |
# CouchRest: CouchDB, close to the metal
CouchRest is based on [CouchDB‘s couch.js test library](svn.apache.org/repos/asf/incubator/couchdb/trunk/share/www/script/couch.js), which I find to be concise, clear, and well designed. CouchRest lightly wraps CouchDB‘s HTTP API, managing JSON serialization, and remembering the URI-paths to CouchDB‘s API endpoints so you don‘t have to.
CouchRest is designed to make a simple base for application and framework-specific object oriented APIs. CouchRest is Object-Mapper agnostic, the parsed JSON it returns from CouchDB shows up as subclasses of Ruby‘s Hash. Naked JSON, just as it was mean to be.
## Easy Install
Easy Install is moving to RubyForge, heads up for the gem.
### Relax, it‘s RESTful
The core of Couchrest is Heroku’s excellent REST Client Ruby HTTP wrapper. REST Client takes all the nastyness of Net::HTTP and gives is a pretty face, while still giving you more control than Open-URI. I recommend it anytime you’re interfacing with a well-defined web service.
### Running the Specs
The most complete documentation is the spec/ directory. To validate your CouchRest install, from the project root directory run `rake`, or `autotest` (requires RSpec and optionally ZenTest for autotest support).
## Examples
Quick Start:
# with !, it creates the database if it doesn't already exist @db = CouchRest.database!("http://127.0.0.1:5984/couchrest-test") response = @db.save_doc({:key => 'value', 'another key' => 'another value'}) doc = @db.get(response['id']) puts doc.inspect
Bulk Save:
@db.bulk_save([ {"wild" => "and random"}, {"mild" => "yet local"}, {"another" => ["set","of","keys"]} ]) # returns ids and revs of the current docs puts @db.documents.inspect
Creating and Querying Views:
@db.save_doc({ "_id" => "_design/first", :views => { :test => { :map => "function(doc){for(var w in doc){ if(!w.match(/^_/))emit(w,doc[w])}}" } } }) puts @db.view('first/test')['rows'].inspect
## CouchRest::Model
CouchRest::Model has been deprecated and replaced by CouchRest::ExtendedDocument
## CouchRest::ExtendedDocument
### Callbacks
`CouchRest::ExtendedDocuments` instances have 2 callbacks already defined for you:
`create_callback`, `save_callback`, `update_callback` and `destroy_callback`
In your document inherits from `CouchRest::ExtendedDocument`, define your callback as follows:
save_callback :before, :generate_slug_from_name
CouchRest uses a mixin you can find in lib/mixins/callbacks which is extracted from Rails 3, here are some simple usage examples:
save_callback :before, :before_method save_callback :after, :after_method, :if => :condition save_callback :around {|r| stuff; yield; stuff }
Check the mixin or the ExtendedDocument class to see how to implement your own callbacks.
### Casting
Often, you will want to store multiple objects within a document, to be able to retrieve your objects when you load the document, you can define some casting rules.
property :casted_attribute, :cast_as => 'WithCastedModelMixin' property :keywords, :cast_as => ["String"]
If you want to cast an array of instances from a specific Class, use the trick shown above ["ClassName"]