# Assign slot_number
if self.slot_number.nil?
- try_slot = 1
- begin
- self.slot_number = try_slot
+ while true
+ n = self.class.available_slot_number
+ if n.nil?
+ raise "No available node slots"
+ end
+ self.slot_number = n
begin
self.save!
break
rescue ActiveRecord::RecordNotUnique
- try_slot += 1
+ # try again
end
- raise "No available node slots" if try_slot == Rails.configuration.max_compute_nodes
- end while true
+ end
end
# Assign hostname
protected
+ def self.available_slot_number
+ connection.exec_query('SELECT n FROM generate_series(1, $1) AS slot(n)
+ LEFT JOIN nodes ON n=slot_number
+ WHERE slot_number IS NULL
+ LIMIT 1',
+ # query label:
+ 'Node.available_slot_number',
+ # [col_id, val] for $1 vars:
+ [['max_compute_nodes',
+ Rails.configuration.max_compute_nodes]],
+ ).rows.first.andand.first
+ end
+
def ensure_ping_secret
self.info['ping_secret'] ||= rand(2**256).to_s(36)
end
test "ping two nodes one with no hostname and one with hostname and check hostnames" do
# ping node with no hostname and expect it set with config format
node = ping_node(:new_with_no_hostname, {})
- slot_number = node.slot_number
refute_nil node.slot_number
- assert_equal "compute#{slot_number}", node.hostname
+ assert_equal "compute#{node.slot_number}", node.hostname
# ping node with a hostname and expect it to be unchanged
node2 = ping_node(:new_with_custom_hostname, {})
assert_equal '10.5.5.5', n1.ip_address
end
end
+
+ test 'run out of slots' do
+ Rails.configuration.max_compute_nodes = 3
+ act_as_system_user do
+ Node.destroy_all
+ (1..4).each do |i|
+ n = Node.create!
+ args = { ip: "10.0.0.#{i}", ping_secret: n.info['ping_secret'] }
+ if i <= Rails.configuration.max_compute_nodes
+ n.ping(args)
+ else
+ assert_raises do
+ n.ping(args)
+ end
+ end
+ end
+ end
+ end
end