A very stupid local JSON store.
It’s built on top of yajl-ruby and File.lock. Defaults to ‘json’ (or ‘json_pure’) if yajl-ruby is not present (it’s probably just a “gem install yajl-ruby” away.
Strives to be process-safe and thread-safe.
The philosophy here is : every document has a revision number. You have to provide the latest revision number in order to update sucessfully a document (else the ‘put’ will fail and you’ll return the latest version of the document (as a new starting point)).
A cloche assumes your documents have a ‘type’ and it stores documents in separate dirs, one per type.
WARNING : this library works on windows but without locking (only thread sync).
Basic operations :
require 'rubygems' require 'rufus-cloche' # gem install rufus-cloche c = Rufus::Cloche.new(:dir => 'my_cloche') doc = { '_id' => 'invitation05', 'type' => 'letter', 'to' => 'The Duke' } # documents are Hash instances, with an '_id' and a 'type' key. d = c.put(doc) p d # => nil # #put returned nil, the 'insertion' was successful p doc['_rev'] # => 0 # Cloche added the '_rev' key and set its value to 0. # ... meanwhile, someone in another process upated the document # we're trying to put an updated version ... doc['body'] = "Dear Monty, it's been a while since El Alamein..." d = c.put(doc) p d # => { "_id" => "invitation05", "type"=>"letter", "to" => "The Count", "_rev" => 1 } # # the update failed, the method returned the current version of the document
It’s OK to get a document, but it’s sometimes better to get many of them :
docs = get_many('letter') # returns an array containing *all* the documents with the type 'letter' docs = get_many('letter', /^invitation/) # returns all the documents whose _id begins with "invitation" docs = get_many('letter', /\/2009\//) # returns all the 2009 letters (assuming their _id contains the string "/2009/"
On the rufus-ruby list :
groups.google.com/group/rufus-ruby
github.com/jmettraux/rufus-cloche/issues
irc.freenode.net #ruote
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John Mettraux, [email protected], jmettraux.wordpress.com
MIT