mecano

# Mecano Mecano gather a set of functions usually used during system deployment. All the functions share a common API with flexible options. * Run actions both locally and remotely over SSH. * Ability to see if an action had an effect through the second argument provided in the callback. * Common API with options and callback arguments and calling the callback with an error and the number of affected actions. * Run one or multiple actions depending on option argument being an object or an array of objects. ## Source Code module.exports = -> # obj = instance arguments... if arguments.length is 2 obj = arguments[0] obj.options = arguments[1] else if arguments.length is 1 obj = {} obj.options = arguments[0] else obj = {} obj.options = {} obj.registry ?= {} obj.propagated_options ?= [] for option in module.exports.propagated_options then obj.propagated_options.push option properties = {} stack = [] todos = [] todos.err = null todos.changed = false todos.throw_if_error = true call_callback = (fn, args) -> stack.unshift todos todos = [] todos.err = null todos.changed = false todos.throw_if_error = true try fn.apply obj, args catch err todos = stack.shift() jump_to_error err return run() mtodos = todos todos = stack.shift() todos.unshift mtodos... if mtodos.length call_sync = (fn, args) -> stack.unshift todos todos = [] todos.err = null todos.changed = false todos.throw_if_error = true try status = fn.apply obj, args catch err todos = stack.shift() jump_to_error err return run() mtodos = todos todos = stack.shift() todos.unshift mtodos... if mtodos.length status # call_async = (fn, local_options={}, callback, name) -> # Options are: type, args, handler call_async = (action) -> global_options = obj.options parent_options = todos.options local_options = action.args[0] callback = action.args[1] local_options ?= {} local_options_array = Array.isArray local_options local_options = [local_options] unless local_options_array options = [] for local_opts in local_options local_opts = argument: local_opts if local_opts? and typeof local_opts isnt 'object' opts = {} for k, v of local_opts then opts[k] = local_opts[k] options.push opts for k, v of parent_options for opts in options then opts[k] = v if opts[k] is undefined and k in obj.propagated_options for k, v of global_options for opts in options then opts[k] = v if opts[k] is undefined try stack.unshift todos todos = [] todos.err = null todos.changed = false todos.throw_if_error = true status_callback = [] status_action = [] finish = (err) -> arguments.length = 2 if arguments.length is 0 todos = stack.shift() if todos.length is 0 todos.throw_if_error = false if err and callback jump_to_error err if err status_callback = status_callback.some (status) -> !! status status_action = status_action.some (status) -> !! status callback_args = [err, status_callback, [].slice.call(arguments)[1...]...] call_callback callback, callback_args if callback todos.changed = true if status_action and not options.shy return run() options = options[0] unless local_options_array wrap obj, [options, finish], (options, callback) -> todos.options = options action.handler.call obj, options, (err, status, args...) -> status_callback.push status status_action.push status unless options.shy setImmediate -> callback err, status, args... catch err todos = stack.shift() jump_to_error err run() jump_to_error = (err) -> while todos[0] and todos[0].type isnt 'then' then todos.shift() todos.err = err # return run() run = -> todo = todos.shift() unless todo # Nothing more to do in current queue throw todos.err if todos.err and todos.throw_if_error return if todo.type is 'then' {err, changed} = todos todos.err = null todos.changed = false todos.throw_if_error = true todo.args[0].call obj, err, changed run() return if todo.type is 'call' if todo.args[0].length is 2 # Async style return call_async type: todo.type args: todo.args handler: todo.args[0] else # Sync style changed = call_sync todo.args[0], [] if changed then todos.changed = true return run() # Call the action todo.args[0].user_args = todo.args[1]?.length > 2 fn = obj.registry[todo.type] or registry[todo.type] call_async type: todo.type args: todo.args handler: obj.registry[todo.type] or registry[todo.type] properties.child = get: -> -> module.exports(obj.options) properties.then = get: -> -> todos.push type: 'then', args: arguments process.nextTick run if todos.length is 1 # Activate the pump obj properties.call = get: -> -> todos.push type: 'call', args: arguments process.nextTick -> process.nextTick run if todos.length is 1 # Activate the pump obj proto = Object.defineProperties obj, properties # Register function Object.defineProperty obj, 'register', get: -> (name, handler) -> is_registered_locally = obj.registered name, true if handler is null or handler is false if is_registered_locally delete obj.registry[name] delete obj[name] else if module.exports.registered name throw Error 'Unregister a global function from local context' return obj throw Error "Function already defined '#{name}'" if is_registered_locally obj.registry[name] = handler Object.defineProperty obj, name, configurable: true, get: -> -> # id = status.id++ dest = arguments[0]?.destination todos.push type: name, args: arguments process.nextTick run if todos.length is 1 # Activate the pump obj Object.defineProperty obj, 'registered', get: -> (name, local_only=false) -> global = Object.prototype.hasOwnProperty.call module.exports, name local = Object.prototype.hasOwnProperty.call obj, name if local_only then local else global or local obj.register name, handler for name, handler of registry obj module.exports.propagated_options = ['ssh', 'log', 'stdout', 'stderr'] ## Register functions Register a new function available when requiring mecano and inside any mecano instance. You can also un-register a existing function by passing "null" or "false" as the second argument. It will return "true" if the function is un-registered or "false" if there was nothing to do because the function wasn't already registered. register = module.exports.register = (name, handler) -> if handler is null or handler is false delete registry[name] if registered name delete module.exports[name] if registered name return module.exports throw Error "Function already defined '#{name}'" if registered name registry[name] = handler unless name is 'call' Object.defineProperty module.exports, name, configurable: true get: -> module.exports()[name] registered = module.exports.registered = (name) -> Object.prototype.hasOwnProperty.call module.exports, name Pre-register mecano internal functions registry = require './misc/registry' register name, handler for name, handler of registry register 'call', module.exports().call wrap = require './misc/wrap'