couchrest_model/README.md

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# CouchRest: CouchDB, close to the metal
CouchRest is based on [CouchDB's couch.js test
library](http://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.
Note: CouchRest only support CouchDB 0.9.0 or newer.
## Easy Install
Easy Install is moving to RubyForge, heads up for the gem.
### Relax, it's RESTful
The core of Couchrest is Herokus 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
youre 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"]
property :occurs_at, :cast_as => 'Time'
property :end_date, :cast_as => 'Date'
property :last_name, :alias => :family_name
property :read_only_value, :read_only => true
property :name, :length => 4...20
property :price, :type => Integer
If you want to cast an array of instances from a specific Class, use the trick shown above ["ClassName"]