Ah ok. I wasn't sure how to do that, and figured I'd follow the 'create_table' syntax. I'll have a go at the instance_eval version though. Always good to learn new stuff. :) Cheers, Taryn
On Dec 16, 5:59 pm, Joshua Peek <[email protected]> wrote: > Looks good. > > DHH would recommend using instance_eval for the schema block just to > clean up the "s." > > On Dec 15, 3:58 am, taryneast <[email protected]> wrote: > > > So, following on from the original discussion-thread > > here:http://groups.google.com/group/rubyonrails-core/browse_thread/thread/... > > > I've built some baseline functionality for defining a schema for an > > Active Resource. > > > Code available as a patch here:http://pastie.org/743842 > > > and a more-readable combined diff here:http://pastie.org/743843 > > > What you can now do is this: > > > class FlickrPhoto << ActiveResource::Base > > > define_schema do |s| > > s.string :photo, :title > > s.integer :width, :height > > s.float :some_other_attribute > > s.attribute 'and_another', 'string' > > end > > > validates_presence_of :photo > > validates_numericality_of :width, :height > > end > > > # this works > > my_photo = FlickrPhoto.new(:photo => 'photo_stream_here', :title => > > 'eben', :tags => ['cat']) > > my_photo.valid? # => true > > my_photo.save # => true > > my_photo.photo # 'photo_stream_here' > > > # and now, so does this: > > new_photo = FlickrPhoto.new() > > new_photo.respond_to? :photo # => true > > new_photo.photo # => nil > > new_photo.valid? # => false > > > new_photo.known_attributes # => ['photo', 'title', 'height', > > 'width', 'some_other_attribute', 'and_another'] > > > # and if you fetch and existing one: > > a_photo = FlickrPhoto.find(1) # <FlickrPhoto><photo>abcdef</ > > photo><width>123</width><instance_attribute>456</instance_attribute></ > > FlickrPhoto> > > a_photo.photo # => 'abcdef' > > a_photo.width # => '123' # note: still a > > string > > a_photo.instance_attribute # => '456' # note: also a string > > > a_photo.known_attributes # => ['photo', 'title', 'height', > > 'width', 'some_other_attribute', 'and_another', 'instance_attribute'] > > > new_photo.respond_to? 'instance_attribute' # => false (because it's > > not a known_attribute) > > > More details on what/how in the rdoc for define_schema :) > > > To summarise: > > 1) You can define a schema using 'define_schema' and passing a block, > > or passing a hash to 'schema=' > > 2) this populates a set of 'known_attributes' that are added to the > > list of attributes currently on an instance (if there's no schema, > > this means that the known_attributes equals the existing attributes on > > the instance - as it always has done). > > 3) known attributes will return 'true' to a 'respond_to?' and will not > > cause a 'NoMethodError' if invoked > > 4) it will also store the 'attribute type' against each attribute - > > currently this does nothing... but my next step is to add a typecast > > based on this, along with "attributes_before_typecast" ala Active > > Record. This will be extremely useful for integer values as I've found > > my own code peppered with "to_i" checks for attributes that I already > > know are meant to be integers :P > > 5) an extension will also allow us to pass in options. The only > > sensible one that I can see so far is ":default => 'blah') which will, > > of course, set up known attributes with their given defaults - unless > > otherwise specified. > > > Cheers, > > Taryn > > -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Core" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-core?hl=en.
