class Chef::Provisioning::Driver
A Driver
instance represents a place where machines can be created and found, and contains methods to create, delete, start, stop, and find them.
For AWS, a Driver
instance corresponds to a single account. For Vagrant, it is a directory where VM files are found.
How to Make a Driver
¶ ↑
To implement a Driver
, you must implement the following methods:
-
initialize(
driver_url
) - create a new driver with the given URL -
driver_url
- a URL representing everything unique about your driver. (NOT credentials) -
allocate_machine
- ask the driver to allocate a machine to you. -
ready_machine
- get the machine “ready” - wait for it to be booted and accessible (for example, accessible via SSH transport). -
stop_machine
- stop the machine. -
destroy_machine
- delete the machine. -
connect_to_machine
- connect to the given machine.
Optionally, you can also implement:
-
allocate_machines
- allocate an entire group of machines. -
ready_machines
- get a group of machines warm and booted. -
stop_machines
- stop a group of machines. -
destroy_machines
- delete a group of machines.
Additionally, you must create a file named `chef/provisioning/driver_init/<scheme>.rb`, where <scheme> is the name of the scheme you chose for your driver_url. This file, when required, must call Chef::Provisioning.add_registered_driver(<scheme>, <class>). The given <class>.from_url(url, config) will be called with a driver_url
and configuration.
All of these methods must be idempotent - if the work is already done, they just don't do anything.
Attributes
A configuration hash. These keys may be present:
- :driver_options: a driver-defined object containing driver config. - :private_keys: a hash of private keys, with a "name" and a "value". Values are either strings (paths) or PrivateKey objects. - :private_key_paths: a list of paths to directories containing private keys. - :write_private_key_path: the path to which we write new keys by default. - :log_level: :debug/:info/:warn/:error/:fatal - :chef_server_url: url to chef server - :node_name: username to talk to chef server - :client_key: path to key used to talk to chef server
A URL representing the driver and the place where machines come from. This will be stuffed in machine_spec.reference so that the machine can be re-inflated. URLs must have a unique scheme identifying the driver class, and enough information to identify the place where created machines can be found. For AWS, this is the account number; for lxc and vagrant, it is the directory in which VMs and containers are.
For example:
-
fog:AWS:123456789012
-
vagrant:/var/vms
-
lxc:
-
docker:
Public Class Methods
Override this on specific driver classes
# File lib/chef/provisioning/driver.rb, line 56 def self.from_url(driver_url, config) Chef::Provisioning.from_url(driver_url, config) end
Inflate a driver from a driver URL.
@param [String] driver_url
the URL to inflate the driver config - a configuration hash. See “config” for a list of known keys.
Returns¶ ↑
A Driver
representing the given driver_url.
# File lib/chef/provisioning/driver.rb, line 48 def initialize(driver_url, config) @driver_url = driver_url @config = config end
Public Instance Methods
Allocate an image. Returns quickly with an ID that tracks the image.
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method @param [Chef::Provisioning::ManagedEntry] image_spec An image specification representing this image. @param [Hash] image_options A set of options representing the desired state of the image @param [Chef::Provisioning::ManagedEntry] machine_spec A machine specification representing this machine. @param [Hash] machine_options A set of options representing the desired state of the machine used to create the image
# File lib/chef/provisioning/driver.rb, line 173 def allocate_image(action_handler, image_spec, image_options, machine_spec, machine_options) raise "#{self.class} does not implement create_image" end
Allocate a load balancer @param [Chef::Provisioning::ActionHandler] action_handler The action handler @param [Chef::Provisioning::ManagedEntry] lb_spec Frozen LB specification @param [Hash] lb_options A hash of options to pass the LB @param [Array] machine_specs An array of machine specs
the load balancer should have. `nil` indicates "leave the set of machines alone," or for new LBs, it means "no machines."
# File lib/chef/provisioning/driver.rb, line 279 def allocate_load_balancer(action_handler, lb_spec, lb_options, machine_specs) end
Allocate a machine from the underlying service. This method does not need to wait for the machine to boot or have an IP, but it must store enough information in machine_spec.reference to find the machine later in ready_machine.
If a machine is powered off or otherwise unusable, this method may start it, but does not need to wait until it is started. The idea is to get the gears moving, but the job doesn't need to be done :)
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method @param [Chef::Provisioning::ManagedEntry] machine_spec A machine specification representing this machine. @param [Hash] machine_options A set of options representing the desired options when constructing the machine
@return [Chef::Provisioning::ManagedEntry] Modifies the passed-in machine_spec. Anything in here will be saved back after allocate_machine
completes.
# File lib/chef/provisioning/driver.rb, line 112 def allocate_machine(action_handler, machine_spec, machine_options) raise "#{self.class} does not implement allocate_machine" end
Allocate a set of machines. This should have the same effect as running allocate_machine
on all machine_specs.
Drivers do not need to implement this; the default implementation calls acquire_machine in parallel.
Parallelizing¶ ↑
The parallelizer must implement parallelize @example Example parallelizer
parallelizer.parallelize(specs_and_options) do |machine_spec| allocate_machine(action_handler, machine_spec) end.to_a # The to_a at the end causes you to wait until the parallelization is done
This object is shared among other chef-provisioning actions, ensuring that you do not go over parallelization limits set by the user. Use of the parallelizer to parallelizer machines is not required.
Passing a block¶ ↑
If you pass a block to this function, each machine will be yielded to you as it completes, and then the function will return when all machines are yielded.
@example Passing a block
allocate_machines(action_handler, specs_and_options, parallelizer) do |machine_spec| ... end
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method; this
is generally a driver, but could be anything that can support the interface (i.e., in the case of the test kitchen provisioning driver for acquiring and destroying VMs).
@param [Hash] specs_and_options A hash of machine_spec -> machine_options representing the
machines to allocate.
@param [Parallelizer] parallelizer an object with a parallelize() method that works like this: @return [Array<Machine>] An array of machine objects created
# File lib/chef/provisioning/driver.rb, line 239 def allocate_machines(action_handler, specs_and_options, parallelizer) parallelizer.parallelize(specs_and_options) do |machine_spec, machine_options| allocate_machine(add_prefix(machine_spec, action_handler), machine_spec, machine_options) yield machine_spec if block_given? machine_spec end.to_a end
Connect to a machine without allocating or readying it. This method will NOT make any changes to anything, or attempt to wait.
@param [Chef::Provisioning::ManagedEntry] machine_spec ManagedEntry
representing this machine. @param [Hash] machine_options @return [Machine] A machine object pointing at the machine, allowing useful actions like setup, converge, execute, file and directory.
# File lib/chef/provisioning/driver.rb, line 142 def connect_to_machine(machine_spec, machine_options) raise "#{self.class} does not implement connect_to_machine" end
Destroy an image using this service.
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method @param [Chef::Provisioning::ManagedEntry] image_spec An image specification representing this image. @param [Hash] image_options A set of options representing the desired state of the image @param [Hash] machine_options A set of options representing the desired state of the machine used to create the image
# File lib/chef/provisioning/driver.rb, line 192 def destroy_image(action_handler, image_spec, image_options, machine_options={}) raise "#{self.class} does not implement destroy_image" end
Destroy the load balancer @param [ChefMetal::ActionHandler] action_handler The action handler @param [ChefMetal::LoadBalancerSpec] lb_spec Frozen LB specification @param [Hash] lb_options A hash of options to pass the LB
# File lib/chef/provisioning/driver.rb, line 296 def destroy_load_balancer(action_handler, lb_spec, lb_options) end
Delete the given machine – destroy the machine, returning things to the state before allocate_machine
was called.
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method @param [Chef::Provisioning::ManagedEntry] machine_spec A machine specification representing this machine. @param [Hash] machine_options A set of options representing the desired state of the machine
# File lib/chef/provisioning/driver.rb, line 153 def destroy_machine(action_handler, machine_spec, machine_options) raise "#{self.class} does not implement destroy_machine" end
Delete machines in batch, in parallel if possible.
# File lib/chef/provisioning/driver.rb, line 265 def destroy_machines(action_handler, specs_and_options, parallelizer) parallelizer.parallelize(specs_and_options) do |machine_spec, machine_options| destroy_machine(add_prefix(machine_spec, action_handler), machine_spec, machine_options) yield machine_spec if block_given? end.to_a end
Ready an image, waiting till the point where it is ready to be used.
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method @param [Chef::Provisioning::ManagedEntry] image_spec An image specification representing this image. @param [Hash] image_options A set of options representing the desired state of the image
# File lib/chef/provisioning/driver.rb, line 182 def ready_image(action_handler, image_spec, image_options) raise "#{self.class} does not implement ready_image" end
Make the load balancer ready @param [Chef::Provisioning::ActionHandler] action_handler The action handler @param [Chef::Provisioning::ManagedEntry] lb_spec Frozen LB specification @param [Hash] lb_options A hash of options to pass the LB @param [Array] machine_specs An array of machine specs
the load balancer should have. `nil` indicates "leave the set of machines alone," or for new LBs, it means "no machines."
# File lib/chef/provisioning/driver.rb, line 289 def ready_load_balancer(action_handler, lb_spec, lb_options, machine_specs) end
Ready a machine, to the point where it is running and accessible via a transport. This will NOT allocate a machine, but may kick it if it is down. This method waits for the machine to be usable, returning a Machine
object pointing at the machine, allowing useful actions like setup, converge, execute, file and directory.
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method @param [Chef::Provisioning::ManagedEntry] machine_spec A machine specification representing this machine. @param [Hash] machine_options A set of options representing the desired state of the machine
@return [Machine] A machine object pointing at the machine, allowing useful actions like setup, converge, execute, file and directory.
# File lib/chef/provisioning/driver.rb, line 130 def ready_machine(action_handler, machine_spec, machine_options) raise "#{self.class} does not implement ready_machine" end
Ready machines in batch, in parallel if possible.
# File lib/chef/provisioning/driver.rb, line 248 def ready_machines(action_handler, specs_and_options, parallelizer) parallelizer.parallelize(specs_and_options) do |machine_spec, machine_options| machine = ready_machine(add_prefix(machine_spec, action_handler), machine_spec, machine_options) yield machine if block_given? machine end.to_a end
Stop the given machine.
@param [Chef::Provisioning::ActionHandler] action_handler The action_handler object that is calling this method @param [Chef::Provisioning::ManagedEntry] machine_spec A machine specification representing this machine. @param [Hash] machine_options A set of options representing the desired state of the machine
# File lib/chef/provisioning/driver.rb, line 162 def stop_machine(action_handler, machine_spec, machine_options) raise "#{self.class} does not implement stop_machine" end
Stop machines in batch, in parallel if possible.
# File lib/chef/provisioning/driver.rb, line 257 def stop_machines(action_handler, specs_and_options, parallelizer) parallelizer.parallelize(specs_and_options) do |machine_spec, machine_options| stop_machine(add_prefix(machine_spec, action_handler), machine_spec, machine_options) yield machine_spec if block_given? end.to_a end
Protected Instance Methods
# File lib/chef/provisioning/driver.rb, line 301 def add_prefix(machine_spec, action_handler) AddPrefixActionHandler.new(action_handler, "[#{machine_spec.name}] ") end
# File lib/chef/provisioning/driver.rb, line 305 def get_private_key(name) Cheffish.get_private_key(name, config) end