dm-yaml-adapter

This adapter is for DataMapper. This allows you to persist objects to YAML files and still have the query capabilities of DataMapper. I wouldn't scale this out to a zillion files, but if you have a lot of read action on a small database this could be the project for you. OR use it to better understand DataMapper.


Example usage:

We have to tell datamapper where we will be storing the YAML files. 
directory tells the adapter where to store.

DataMapper.setup(:default, {:adapter => 'yaml', :directory => 'db'})


Trying it out: 

If you want some examples of defining classes, check out the spec directory.

Anyway, assuming you have a decent environment set up, you can try out some examples.

If you want to use irb to try some of this interactively, try 'irb' and then
> load 'irbhelper.irb'

That sets up a basic environment with User and Post resources already defined.

irb(main):001:0> load 'irbhelper.irb'
=> true
irb(main):002:0> u = User.create(:name => 'Bob', :age => 55)
=> #<User user_id=1 name="Bob" age=55>
irb(main):003:0> u.save
=> true
irb(main):004:0> User.all
=> [#<User user_id=1 name="Bob" age=55>]
irb(main):005:0> 

If you use another window to check out the db directory you should have a nice User directory with a 1.yaml file in there, with the data of Bob.

You can also add another object and start playing around with some queries.

irb(main):005:0> User.create(:name => 'Sue', :age => 32)
=> #<User user_id=2 name="Sue" age=32>
irb(main):006:0> User.all(:age => 32)
=> [#<User user_id=2 name="Sue" age=32>]
irb(main):007:0> User.all
=> [#<User user_id=1 name="Bob" age=55>, #<User user_id=2 name="Sue" age=32>]
irb(main):008:0> u.destroy
=> true
irb(main):009:0> User.all
=> [#<User user_id=2 name="Sue" age=32>]
irb(main):010:0>