summaryrefslogtreecommitdiff
path: root/lib/chef/provider.rb
blob: 1751c35129ec4b73aabce9bf53cd260f699fc915 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
#
# Author:: Adam Jacob (<adam@chef.io>)
# Author:: Christopher Walters (<cw@chef.io>)
# Copyright:: Copyright 2008-2016, 2009-2018, Chef Software Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

require "chef/mixin/from_file"
require "chef/mixin/convert_to_class_name"
require "chef/mixin/enforce_ownership_and_permissions"
require "chef/mixin/why_run"
require "chef/mixin/shell_out"
require "chef/mixin/provides"
require "chef/dsl/core"
require "chef/platform/service_helpers"
require "chef/node_map"
require "forwardable"

class Chef
  class Provider
    require "chef/mixin/why_run"
    require "chef/mixin/provides"

    attr_accessor :new_resource
    attr_accessor :current_resource
    attr_accessor :run_context

    attr_reader :recipe_name
    attr_reader :logger

    include Chef::Mixin::WhyRun
    extend Chef::Mixin::Provides
    extend Forwardable

    # includes the "core" DSL and not the "recipe" DSL by design
    include Chef::DSL::Core

    # supports the given resource and action (late binding)
    def self.supports?(resource, action)
      true
    end

    # Defines an action method on the provider, running the block to compile the
    # resources, converging them, and then checking if any were updated (and
    # updating new-resource if so)
    #
    # @since 13.0
    # @param name [String, Symbol] Name of the action to define.
    # @param block [Proc] Body of the action.
    # @return [void]
    def self.action(name, &block)
      # We need the block directly in a method so that `super` works.
      define_method("compile_action_#{name}", &block)
      class_eval <<-EOM
        def action_#{name}
          compile_and_converge_action { compile_action_#{name} }
        end
      EOM
    end

    # Deprecation stub for the old use_inline_resources mode.
    #
    # @return [void]
    def self.use_inline_resources
      # Uncomment this in Chef 13.6.
      # Chef.deprecated(:use_inline_resources, "The use_inline_resources mode is no longer optional and the line enabling it can be removed")
    end

    # delegate to the resource
    #
    def_delegators :@new_resource, :property_is_set?

    #--
    # TODO: this should be a reader, and the action should be passed in the
    # constructor; however, many/most subclasses override the constructor so
    # changing the arity would be a breaking change. Change this at the next
    # break, e.g., Chef 11.
    attr_accessor :action

    def initialize(new_resource, run_context)
      @new_resource = new_resource
      @action = action
      @current_resource = nil
      @run_context = run_context
      @converge_actions = nil

      @logger = if run_context
                  run_context.logger.with_child({ resource: new_resource.name, cookbook: cookbook_name, recipe: recipe_name })
                else
                  Chef::Log.with_child({ resource: new_resource.name, cookbook: cookbook_name, recipe: recipe_name })
                end

      @recipe_name = nil
      @cookbook_name = nil
      self.class.include_resource_dsl_module(new_resource)
    end

    def whyrun_mode?
      Chef::Config[:why_run]
    end

    def whyrun_supported?
      true
    end

    def node
      run_context && run_context.node
    end

    # Used by providers supporting embedded recipes
    def resource_collection
      run_context && run_context.resource_collection
    end

    def cookbook_name
      new_resource.cookbook_name
    end

    def check_resource_semantics!
    end

    def load_current_resource
      raise Chef::Exceptions::Override, "You must override load_current_resource in #{self}"
    end

    def define_resource_requirements
    end

    def cleanup_after_converge
    end

    def action_nothing
      logger.trace("Doing nothing for #{@new_resource}")
      true
    end

    def events
      run_context.events
    end

    def run_action(action = nil)
      @action = action unless action.nil?

      # TODO: it would be preferable to get the action to be executed in the
      # constructor...

      check_resource_semantics!

      # user-defined LWRPs may include unsafe load_current_resource methods that cannot be run in whyrun mode
      if whyrun_mode? && !whyrun_supported?
        events.resource_current_state_load_bypassed(@new_resource, @action, @current_resource)
      else
        load_current_resource
        events.resource_current_state_loaded(@new_resource, @action, @current_resource)
      end

      define_resource_requirements
      process_resource_requirements

      # user-defined providers including LWRPs may
      # not include whyrun support - if they don't support it
      # we can't execute any actions while we're running in
      # whyrun mode. Instead we 'fake' whyrun by documenting that
      # we can't execute the action.
      # in non-whyrun mode, this will still cause the action to be
      # executed normally.
      if whyrun_mode? && (!whyrun_supported? || requirements.action_blocked?(@action))
        events.resource_bypassed(@new_resource, @action, self)
      else
        send("action_#{@action}")
      end

      set_updated_status

      cleanup_after_converge
    end

    def process_resource_requirements
      requirements.run(:all_actions) unless @action == :nothing
      requirements.run(@action)
    end

    def resource_updated?
      !converge_actions.empty? || @new_resource.updated_by_last_action?
    end

    def set_updated_status
      if !resource_updated?
        events.resource_up_to_date(@new_resource, @action)
      else
        events.resource_updated(@new_resource, @action)
        new_resource.updated_by_last_action(true)
      end
    end

    def requirements
      @requirements ||= ResourceRequirements.new(@new_resource, run_context)
    end

    def description(description = "NOT_PASSED")
      if description != "NOT_PASSED"
        @description = description
      end
      @description
    end

    def introduced(introduced = "NOT_PASSED")
      if introduced != "NOT_PASSED"
        @introduced = introduced
      end
      @introduced
    end

    def converge_by(descriptions, &block)
      converge_actions.add_action(descriptions, &block)
    end

    # Create a child run_context, compile the block, and converge it.
    #
    # @api private
    def compile_and_converge_action(&block)
      old_run_context = run_context
      @run_context = run_context.create_child
      return_value = instance_eval(&block)
      Chef::Runner.new(run_context).converge
      return_value
    ensure
      if run_context.resource_collection.any? { |r| r.updated? }
        new_resource.updated_by_last_action(true)
      end
      @run_context = old_run_context
    end

    #
    # Handle patchy convergence safely.
    #
    # - Does *not* call the block if the current_resource's properties match
    #   the properties the user specified on the resource.
    # - Calls the block if current_resource does not exist
    # - Calls the block if the user has specified any properties in the resource
    #   whose values are *different* from current_resource.
    # - Does *not* call the block if why-run is enabled (just prints out text).
    # - Prints out automatic green text saying what properties have changed.
    #
    # @param properties An optional list of property names (symbols). If not
    #   specified, `new_resource.class.state_properties` will be used.
    # @param converge_block The block to do the converging in.
    #
    # @return [Boolean] whether the block was executed.
    #
    def converge_if_changed(*properties, &converge_block)
      if !converge_block
        raise ArgumentError, "converge_if_changed must be passed a block!"
      end

      properties = new_resource.class.state_properties.map { |p| p.name } if properties.empty?
      properties = properties.map { |p| p.to_sym }
      if current_resource
        # Collect the list of modified properties
        specified_properties = properties.select { |property| new_resource.property_is_set?(property) }
        modified = specified_properties.select { |p| new_resource.send(p) != current_resource.send(p) }
        if modified.empty?
          properties_str = if new_resource.sensitive
                             specified_properties.join(", ")
                           else
                             specified_properties.map do |property|
                               "#{property}=" << if new_resource.class.properties[property].sensitive?
                                                   "(suppressed sensitive property)"
                                                 else
                                                   new_resource.send(property).inspect
                                                 end
                             end.join(", ")
                           end
          logger.debug("Skipping update of #{new_resource}: has not changed any of the specified properties #{properties_str}.")
          return false
        end

        # Print the pretty green text and run the block
        property_size = modified.map { |p| p.size }.max
        modified.map! do |p|
          properties_str = if new_resource.sensitive || new_resource.class.properties[p].sensitive?
                             "(suppressed sensitive property)"
                           else
                             "#{new_resource.send(p).inspect} (was #{current_resource.send(p).inspect})"
                           end
          "  set #{p.to_s.ljust(property_size)} to #{properties_str}"
        end
        converge_by([ "update #{current_resource.identity}" ] + modified, &converge_block)

      else
        # The resource doesn't exist. Mark that we are *creating* this, and
        # write down any properties we are setting.
        property_size = properties.map { |p| p.size }.max
        created = properties.map do |property|
          default = " (default value)" unless new_resource.property_is_set?(property)
          properties_str = if new_resource.sensitive || new_resource.class.properties[property].sensitive?
                             "(suppressed sensitive property)"
                           else
                             new_resource.send(property).inspect
                           end
          "  set #{property.to_s.ljust(property_size)} to #{properties_str}#{default}"
        end

        converge_by([ "create #{new_resource.identity}" ] + created, &converge_block)
      end
      true
    end

    def self.provides(short_name, opts = {}, &block)
      Chef.provider_handler_map.set(short_name, self, opts, &block)
    end

    def self.provides?(node, resource)
      Chef::ProviderResolver.new(node, resource, :nothing).provided_by?(self)
    end

    #
    # Include attributes, public and protected methods from this Resource in
    # the provider.
    #
    # If this is set to true, delegate methods are included in the provider so
    # that you can call (for example) `attrname` and it will call
    # `new_resource.attrname`.
    #
    # The actual include does not happen until the first time the Provider
    # is instantiated (so that we don't have to worry about load order issues).
    #
    # @param include_resource_dsl [Boolean] Whether to include resource DSL or
    #   not (defaults to `false`).
    #
    def self.include_resource_dsl?
      false
    end

    # Create the resource DSL module that forwards resource methods to new_resource
    #
    # @api private
    def self.include_resource_dsl_module(resource)
      if include_resource_dsl? && !defined?(@included_resource_dsl_module)
        provider_class = self
        @included_resource_dsl_module = Module.new do
          extend Forwardable
          define_singleton_method(:to_s) { "forwarder module for #{provider_class}" }
          define_singleton_method(:inspect) { to_s }
          # this magic, stated simply, is that any instance method declared directly on
          # the resource we are building, will be accessible from the action_class(provider)
          # instance.  methods declared on Chef::Resource and properties are not inherited.
          dsl_methods =
            resource.class.public_instance_methods +
            resource.class.protected_instance_methods -
            provider_class.instance_methods -
            resource.class.properties.keys -
            resource.class.properties.keys.map { |k| "#{k}=".to_sym } -
            Chef::Resource.instance_methods
          def_delegators(:new_resource, *dsl_methods)
        end
        include @included_resource_dsl_module
      end
    end

    protected

    def converge_actions
      @converge_actions ||= ConvergeActions.new(@new_resource, run_context, @action)
    end

    def recipe_eval(&block)
      # This block has new resource definitions within it, which
      # essentially makes it an in-line Chef run. Save our current
      # run_context and create one anew, so the new Chef run only
      # executes the embedded resources.
      #
      # TODO: timh,cw: 2010-5-14: This means that the resources within
      # this block cannot interact with resources outside, e.g.,
      # manipulating notifies.

      converge_by ("evaluate block and run any associated actions") do
        saved_run_context = run_context
        begin
          @run_context = run_context.create_child
          instance_eval(&block)
          Chef::Runner.new(run_context).converge
        ensure
          @run_context = saved_run_context
        end
      end
    end

  end
end

# Requiring things at the bottom breaks cycles
require "chef/chef_class"
require "chef/mixin/why_run"
require "chef/resource_collection"
require "chef/runner"