Johan Sørensen

CouchObject released!

Friday September 14, 2007

CouchObject 0.0.1 is out, fresh from the sofa. Sit down, relax and read the RDoc.

$ sudo gem install couchobject

Since the last time I’ve taken it in a slightly different direction, focusing more on getting the basics up and running. You see, I’ve realised that CouchDb isn’t really perfect as a general OODB store (though, nothing is stopping you from storing an objects attributes in CouchDb, the Persistable module still does that). I’ll be waiting for GemStone and Rubinius for an awesome OODB. Instead CouchObject focus specifically on documents as it is right now:

>> CouchObject::Database.create!("http://localhost:8888", "roflcopters")
=> {"ok"=>true}
>> db = CouchObject::Database.open("http://localhost:8888/roflcopters")
=> #
>> db.all_documents
=> []

Creating and saving a document

>> doc = CouchObject::Document.new
=> #<CouchObject::Document:0x62708c @id=nil, @attributes={}, @revision=nil>
>> doc.engine_noise = "roflroflrofl"
=> "roflroflrofl"
>> doc.url = "http://www.thinkgeek.com/images/products/zoom/roflcopter.jpg"
=> "http://www.thinkgeek.com/images/products/zoom/roflcopter.jpg"
>> pp doc.save(db)
#<CouchObject::Response:0x4cd934
 @parsed_body=
  {"_rev"=>-1022899809, "_id"=>"4D91304BE683851F0E18871ADA6749D8", "ok"=>true},
 @response=#<Net::HTTPCreated 201 Created readbody=true>>

Get the same document by its id, and convert the response to a document (Just to illustrate it)

>> doc_we_created = db.get(doc.id).to_document
=> #"http://www.thinkgeek.com/images/products/zoom/roflcopter.jpg", "engine_noise"=>"roflroflrofl"}, @revision=-1022899809>
>> doc_we_created.engine_noise
=> "roflroflrofl"
>> doc_we_created.engine_noise = "ROFLROFLROFL"
=> "ROFLROFLROFL"
>> doc_we_created.save(db)
>> db.all_documents
=> [{"_rev"=>1353035433, "_id"=>"4D91304BE683851F0E18871ADA6749D8"}]

Sending a raw request to the db

>> response = db.post("_temp_view", <> pp response.to_document.rows.first
{"_rev"=>1353035433,
 "_id"=>"4D91304BE683851F0E18871ADA6749D8",
 "value"=>
  {"url"=>"http://www.thinkgeek.com/images/products/zoom/roflcopter.jpg",
   "_rev"=>1353035433,
   "_id"=>"4D91304BE683851F0E18871ADA6749D8",
   "engine_noise"=>"ROFLROFLROFL"}}

As you can see the API still needs some ironing out by means of more real world usage. You’ll notice that there’s no nice way of doing view of doing view “queries”. I really really want to create a more familiar Ruby DSL for defining views and sending of temporary views (like the one above). In particular it boils down to one or more of these things:

• A Ruby to Javascript converter (Like this perhaps).
• Ambition is awesome, CouchDb is awesome, sounds like a perfect match to me. LINQ me up.
• Make CouchDb use ruby instead of Javascript for views.

Since I’m lazy, I’m starting from the bottom, more on that later. Because I really want to say:

db.select{|doc| doc.title =~ /foo/ }

There’s a Git repository too

$ git clone git://gitorious.org/projects/couchobject/mainline.git

Patches? Yes please, release your inner couch potato.

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