Add bootdisk support

[sbernhard]

No description provided.

[ekohl]

I haven't reviewed all the details, this is just a superficial review.

[ekohl]

I'm wondering about the design so I'm making various comments inline.

Rather than implementing separate attach and detach ISO requests, should it have a requests to reconfigure the cdrom device where the source file is an optional parameter?

[ekohl]

This doesn't actually attach anything and is only the CDROM XML so naming wise I'd suggest.

Suggested change

	def attach_cdrom_xml(iso_path, target_dev, bus)
	def cdrom_xml(iso_path, target_dev, bus)

[ekohl]

This is a different implementation than what's default when a host is created:

fog-libvirt/lib/fog/libvirt/models/compute/server.rb

Lines 410 to 416 in f5495f3

	xml.disk(:type => "file", :device => "cdrom") do
	xml.driver(:name => "qemu", :type => "raw")
	xml.source(:file => "#{iso_dir}/#{iso_file}")
	xml.target(:dev => "sda", :bus => "scsi")
	xml.readonly
	xml.address(:type => "drive", :controller => 0, :bus => 0, :unit => 0)
	end

If the host already has a cdrom drive, shouldn't it reuse that?

[ekohl]

When a host is created with a cdrom it uses sda as the default:

fog-libvirt/lib/fog/libvirt/models/compute/server.rb

Lines 410 to 416 in f5495f3

	xml.disk(:type => "file", :device => "cdrom") do
	xml.driver(:name => "qemu", :type => "raw")
	xml.source(:file => "#{iso_dir}/#{iso_file}")
	xml.target(:dev => "sda", :bus => "scsi")
	xml.readonly
	xml.address(:type => "drive", :controller => 0, :bus => 0, :unit => 0)
	end

[ekohl]

When is this raised? I don't see API calls here so what could raise an exception?