Sexier migrations in Camping?

camping_migration.rb

# put the following into safe_ar.rb our hack ar.rb or whatever takes your fancy

$SAFE_AR_EXTRAS = %{
  # really, assumption is a terrible name
  def self.schemify(assumption)
    unless SchemaInfo.table_exists?
      ActiveRecord::Schema.define do
        create_table SchemaInfo.table_name do |t|
          t.column :version, :float
        end
      end
    end

    SchemaInfo.find(:first) || SchemaInfo.new(:version => assumption)
  end
  
  def self.safe_create_schema(opts = {})
    opts[:assume] ||= 0
    opts[:version] ||= @final
    if @migrations
      si = schemify(opts[:assume])
      if si.version < opts[:version]
        got_to = nil
        begin
          @migrations.sort_by { |m| m.version }.each do |k|
            got_to = k
            k.migrate(:up) if si.version < k.version and k.version <= opts[:version]
            k.migrate(:down) if si.version > k.version and k.version > opts[:version]
          end
          # this is a boolean
          si.update_attributes(:version => opts[:version])
        rescue => e
          # print the message and return where we got to
          $L.error { e.message }
          got_to
        end
      end
    end
  end
}

Camping::Apps.each do |c|
  c::Models.module_eval $SAFE_AR_EXTRAS
end

# once you have required safe_ar.rb
# change MyCampingApp to your camping app :)

    begin
      baseline = MyCampingApp::Models.schemify(0)
      # $L.debug "Baseline version is #{baseline.version}"
      what = MyCampingApp::Models.safe_create_schema
      if what.respond_to?(:down)
        # $L.debug "Rewinding Schema to last good point due to errors"
        migrations = Models.instance_variable_get("@migrations")
        # how to reverse sort_by ?
        migrations.sort_by { |m| m.version }.reverse.each do |k|
          k.migrate(:down) if what.version > k.version and k.version > baseline.version
        end
        # how to bail?
        # send SIGINT ???
        throw :halt, self
      end
    end