def fetch(opts={})
start = (opts[:start] || Time.now.to_i - 3600).to_s
finish = (opts[:finish] || Time.now.to_i).to_s
function = opts[:function] ? opts[:function].to_s.upcase : "AVERAGE"
args = [@filename, "--start", start, "--end", finish, function]
data = @backend.fetch(*args)
start = data[0]
finish = data[1]
labels = data[2]
values = data[3]
points = {}
labels.each_with_index do |label, index|
points[label] = []
values.each do |tuple|
value = tuple[index].nan? ? nil : tuple[index]
points[label] << value
end
end
{:start => start, :finish => finish, :data => points}
end