aboutsummaryrefslogtreecommitdiffstats
path: root/actionmailer/lib/action_mailer/parameterized.rb
blob: 5e768e710694499135b31ef8b94dd5a995edfca3 (plain) (blame)
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
# frozen_string_literal: true

module ActionMailer
  # Provides the option to parameterize mailers in order to share instance variable
  # setup, processing, and common headers.
  #
  # Consider this example that does not use parameterization:
  #
  #   class InvitationsMailer < ApplicationMailer
  #     def account_invitation(inviter, invitee)
  #       @account = inviter.account
  #       @inviter = inviter
  #       @invitee = invitee
  #
  #       subject = "#{@inviter.name} invited you to their Basecamp (#{@account.name})"
  #
  #       mail \
  #         subject:   subject,
  #         to:        invitee.email_address,
  #         from:      common_address(inviter),
  #         reply_to:  inviter.email_address_with_name
  #     end
  #
  #     def project_invitation(project, inviter, invitee)
  #       @account = inviter.account
  #       @project = project
  #       @inviter = inviter
  #       @invitee = invitee
  #       @summarizer = ProjectInvitationSummarizer.new(@project.bucket)
  #
  #       subject = "#{@inviter.name.familiar} added you to a project in Basecamp (#{@account.name})"
  #
  #       mail \
  #         subject:   subject,
  #         to:        invitee.email_address,
  #         from:      common_address(inviter),
  #         reply_to:  inviter.email_address_with_name
  #     end
  #
  #     def bulk_project_invitation(projects, inviter, invitee)
  #       @account  = inviter.account
  #       @projects = projects.sort_by(&:name)
  #       @inviter  = inviter
  #       @invitee  = invitee
  #
  #       subject = "#{@inviter.name.familiar} added you to some new stuff in Basecamp (#{@account.name})"
  #
  #       mail \
  #         subject:   subject,
  #         to:        invitee.email_address,
  #         from:      common_address(inviter),
  #         reply_to:  inviter.email_address_with_name
  #     end
  #   end
  #
  #   InvitationsMailer.account_invitation(person_a, person_b).deliver_later
  #
  # Using parameterized mailers, this can be rewritten as:
  #
  #   class InvitationsMailer < ApplicationMailer
  #     before_action { @inviter, @invitee = params[:inviter], params[:invitee] }
  #     before_action { @account = params[:inviter].account }
  #
  #     default to:       -> { @invitee.email_address },
  #             from:     -> { common_address(@inviter) },
  #             reply_to: -> { @inviter.email_address_with_name }
  #
  #     def account_invitation
  #       mail subject: "#{@inviter.name} invited you to their Basecamp (#{@account.name})"
  #     end
  #
  #     def project_invitation
  #       @project    = params[:project]
  #       @summarizer = ProjectInvitationSummarizer.new(@project.bucket)
  #
  #       mail subject: "#{@inviter.name.familiar} added you to a project in Basecamp (#{@account.name})"
  #     end
  #
  #     def bulk_project_invitation
  #       @projects = params[:projects].sort_by(&:name)
  #
  #       mail subject: "#{@inviter.name.familiar} added you to some new stuff in Basecamp (#{@account.name})"
  #     end
  #   end
  #
  #   InvitationsMailer.with(inviter: person_a, invitee: person_b).account_invitation.deliver_later
  module Parameterized
    extend ActiveSupport::Concern

    included do
      attr_accessor :params
    end

    module ClassMethods
      # Provide the parameters to the mailer in order to use them in the instance methods and callbacks.
      #
      #   InvitationsMailer.with(inviter: person_a, invitee: person_b).account_invitation.deliver_later
      #
      # See Parameterized documentation for full example.
      def with(params)
        ActionMailer::Parameterized::Mailer.new(self, params)
      end
    end

    class Mailer # :nodoc:
      def initialize(mailer, params)
        @mailer, @params = mailer, params
      end

      private
        def method_missing(method_name, *args)
          if @mailer.action_methods.include?(method_name.to_s)
            ActionMailer::Parameterized::MessageDelivery.new(@mailer, method_name, @params, *args)
          else
            super
          end
        end

        def respond_to_missing?(method, include_all = false)
          @mailer.respond_to?(method, include_all)
        end
    end

    class MessageDelivery < ActionMailer::MessageDelivery # :nodoc:
      def initialize(mailer_class, action, params, *args)
        super(mailer_class, action, *args)
        @params = params
      end

      private
        def processed_mailer
          @processed_mailer ||= @mailer_class.new.tap do |mailer|
            mailer.params = @params
            mailer.process @action, *@args
          end
        end

        def enqueue_delivery(delivery_method, options = {})
          if processed?
            super
          else
            args = @mailer_class.name, @action.to_s, delivery_method.to_s, @params, *@args
            ActionMailer::Parameterized::DeliveryJob.set(options).perform_later(*args)
          end
        end
    end

    class DeliveryJob < ActionMailer::DeliveryJob # :nodoc:
      def perform(mailer, mail_method, delivery_method, params, *args)
        mailer.constantize.with(params).public_send(mail_method, *args).send(delivery_method)
      end
    end
  end
end