8.5.2. Example Gear Placement Algorithms

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time)
  return server_infos.first
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time)
  return server_infos.first
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time)
  unless %w[php-5.3 php-5.4].include? app_props.web_cartridge 
    Rails.logger.debug("'#{app_props.web_cartridge}' is not a PHP app; selecting a node normally.")
    return OpenShift::MCollectiveApplicationContainerProxy.select_best_fit_node_impl(server_infos)
  end
  php_hosts = Broker::Application.config.gear_placement[:php_hosts]
  Rails.logger.debug("selecting a php node from: #{php_hosts.join ', '}")
  # figure out which of the nodes given is allowed for php carts
  matched_server_infos = server_infos.select {|x| php_hosts.include?(x.name) }
  matched_server_infos.empty? and
    raise "The gear-placement PHP_HOSTS setting doesn't match any of the NodeProfile names"
  return matched_server_infos.sample #chooses randomly from the matched hosts
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time)
  unless %w[php-5.3 php-5.4].include? app_props.web_cartridge 
    Rails.logger.debug("'#{app_props.web_cartridge}' is not a PHP app; selecting a node normally.")
    return OpenShift::MCollectiveApplicationContainerProxy.select_best_fit_node_impl(server_infos)
  end
  php_hosts = Broker::Application.config.gear_placement[:php_hosts]
  Rails.logger.debug("selecting a php node from: #{php_hosts.join ', '}")
  # figure out which of the nodes given is allowed for php carts
  matched_server_infos = server_infos.select {|x| php_hosts.include?(x.name) }
  matched_server_infos.empty? and
    raise "The gear-placement PHP_HOSTS setting doesn't match any of the NodeProfile names"
  return matched_server_infos.sample #chooses randomly from the matched hosts
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  config = Broker::Application.config.gear_placement  
  pinned_user = config[:pinned_user]           
  if pinned_user == user_props.login
    slow_hosts = config[:slow_hosts]
    Rails.logger.debug("user '#{pinned_user}' needs a gear; restrict to '#{slow_hosts.join ', '}'")
    matched_server_infos = server_infos.select {|x| slow_hosts.include?(x.name)}
    matched_server_infos.empty? and
      raise "The gear-placement SLOW_HOSTS setting does not match any available NodeProfile names"
    return matched_server_infos.first
  else
    Rails.logger.debug("user '#{user_props.login}' is not pinned; choose a node normally")
    return OpenShift::MCollectiveApplicationContainerProxy.select_best_fit_node_impl(server_infos)
  end
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  config = Broker::Application.config.gear_placement  
  pinned_user = config[:pinned_user]           
  if pinned_user == user_props.login
    slow_hosts = config[:slow_hosts]
    Rails.logger.debug("user '#{pinned_user}' needs a gear; restrict to '#{slow_hosts.join ', '}'")
    matched_server_infos = server_infos.select {|x| slow_hosts.include?(x.name)}
    matched_server_infos.empty? and
      raise "The gear-placement SLOW_HOSTS setting does not match any available NodeProfile names"
    return matched_server_infos.first
  else
    Rails.logger.debug("user '#{user_props.login}' is not pinned; choose a node normally")
    return OpenShift::MCollectiveApplicationContainerProxy.select_best_fit_node_impl(server_infos)
  end
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  Rails.logger.debug("Using blacklist gear placement plugin to choose node.")
  Rails.logger.debug("selecting from nodes: #{server_infos.map(:name).join ', '}")
  blacklisted_vendor = Broker::Application.config.gear_placement[:blacklisted_vendor]
  unless blacklisted_vendor.nil?    
    comp_list.each do |comp|
      if blacklisted_vendor == comp.cartridge_vendor      
        raise "Applications containing cartridges from #{blacklisted_vendor} are blacklisted"
      end
    end
  end
  Rails.logger.debug("no contraband found, choosing node as usual")
  return OpenShift::MCollectiveApplicationContainerProxy.select_best_fit_node_impl(server_infos)
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  Rails.logger.debug("Using blacklist gear placement plugin to choose node.")
  Rails.logger.debug("selecting from nodes: #{server_infos.map(:name).join ', '}")
  blacklisted_vendor = Broker::Application.config.gear_placement[:blacklisted_vendor]
  unless blacklisted_vendor.nil?    
    comp_list.each do |comp|
      if blacklisted_vendor == comp.cartridge_vendor      
        raise "Applications containing cartridges from #{blacklisted_vendor} are blacklisted"
      end
    end
  end
  Rails.logger.debug("no contraband found, choosing node as usual")
  return OpenShift::MCollectiveApplicationContainerProxy.select_best_fit_node_impl(server_infos)
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  # collect memory statistic from all nodes
  memhash = Hash.new(0)
  OpenShift::MCollectiveApplicationContainerProxy.rpc_get_fact('memoryfree') {|name,mem| memhash[name] = to_bytes(mem)}
  Rails.logger.debug("node memory hash: #{memhash.inspect}")
  # choose the one from our list with the largest value
  return server_infos.max_by {|server| memhash[server.name]} 
end

def self.to_bytes(mem)
  mem.to_f * case mem
    when /TB/; 1024 ** 4
    when /GB/; 1024 ** 3
    when /MB/; 1024 ** 2
    when /KB/; 1024
    else     ; 1
  end
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  # collect memory statistic from all nodes
  memhash = Hash.new(0)
  OpenShift::MCollectiveApplicationContainerProxy.rpc_get_fact('memoryfree') {|name,mem| memhash[name] = to_bytes(mem)}
  Rails.logger.debug("node memory hash: #{memhash.inspect}")
  # choose the one from our list with the largest value
  return server_infos.max_by {|server| memhash[server.name]} 
end

def self.to_bytes(mem)
  mem.to_f * case mem
    when /TB/; 1024 ** 4
    when /GB/; 1024 ** 3
    when /MB/; 1024 ** 2
    when /KB/; 1024
    else     ; 1
  end
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  return server_infos.sort_by {|x| x.node_consumed_capacity.to_f}.first
end

def self.select_best_fit_node_impl(server_infos, app_props, current_gears, comp_list, user_props, request_time) 
  return server_infos.sort_by {|x| x.node_consumed_capacity.to_f}.first
end