docs/usage_of_api_attachments_in_ruby_on_rails.md
# How to use API delivery system that add attachments to the mailer method in Ruby on Rails
Let's use mailer method which was defined [here](https://github.com/MailToolbox/mail_plugger/blob/main/docs/usage_in_ruby_on_rails.md#api).
Change the API and `MailPlugger.plug_in` method in `config/initializers/mail_plugger.rb`.
```ruby
# NOTE: This is just an example for testing...
class TestApiClientClass
def initialize(options = {})
@settings = { api_key: '12345' }
@options = options
end
def deliver
# e.g. API.new(@settings).client.post(generate_mail_hash)
puts " >>> settings: #{@settings.inspect}"
puts " >>> options: #{@options.inspect}"
puts " >>> generate_mail_hash: #{generate_mail_hash.inspect}"
{ response: 'OK' }
end
private
def generate_mail_hash
{
to: generate_recipients,
from: {
email: @options[:from].first
},
subject: @options[:subject],
content: [
{
type: 'text/plain',
value: @options[:text_part]
},
{
type: 'text/html; charset=UTF-8',
value: @options[:html_part]
}
],
attachments: generate_attachments
}
end
def generate_recipients
@options[:to].map do |to|
{
email: to
}
end
end
def generate_attachments
@options[:attachments].map do |attachment|
hash = {
filename: attachment[:filename],
type: attachment[:type],
content: attachment[:content]
}
hash.merge!(content_id: attachment[:cid]) if attachment.has_key?(:cid)
hash
end
end
end
MailPlugger.plug_in('test_api_client') do |api|
api.client = TestApiClientClass
api.delivery_options = %i[from to subject text_part html_part attachments]
api.delivery_settings = { return_response: true }
end
```
Let's change `app/mailers/test_mailer.rb` file.
```ruby
class TestMailer < ApplicationMailer
default from: 'from@example.com'
def send_test
attachments['image1.png'] = File.read('/path/to/image1.png')
attachments.inline['image2.png'] = File.read('/path/to/image2.png')
mail subject: 'Test email', to: 'to@example.com'
end
end
```
Then change `app/views/test_mailer/send_test.html.erb` and add inline attachment.
```erb
<p>Test email body</p>
<%= image_tag attachments['image2.png'].url %>
```
In the `rails console` we can try it out.
```ruby
TestMailer.send_test.deliver_now!
# Rendering test_mailer/send_test.html.erb within layouts/mailer
# Rendered test_mailer/send_test.html.erb within layouts/mailer (4.6ms)
# Rendering test_mailer/send_test.text.erb within layouts/mailer
# Rendered test_mailer/send_test.text.erb within layouts/mailer (0.3ms)
#TestMailer#send_test: processed outbound mail in 47.5ms
# >>> settings: {:api_key=>"12345"}
# >>> options: {"from"=>["from@example.com"], "to"=>["to@example.com"], "subject"=>"Test email", "text_part"=>"Test email body\n\n", "html_part"=>"<!DOCTYPE html>\n<html>\n <head>\n <meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\" />\n <style>\n /* Email styles need to be inline */\n </style>\n </head>\n\n <body>\n <p>Test email body</p>\n<img src=\"cid:5ffdd449d282a_163e2ef9c62c0@server.local.mail\" />\n\n </body>\n</html>\n", "attachments"=>[{"filename"=>"image1.png", "type"=>"image/png", "content"=>"iVBORw0KGgoAAAANSUhEUgAAALQAAABdCAMAAAA7WLggg==\n"}, {"cid"=>"5ffdd449d282a_163e2ef9c62c0@server.local.mail", "filename"=>"image2.png", "type"=>"image/png", "content"=>"iVBORw0KGgoAAAANSUhEUgAAAAggg==\n"}]}
# >>> generate_mail_hash: {:to=>[{:email=>"to@example.com"}], :from=>{:email=>"from@example.com"}, :subject=>"Test email", :content=>[{:type=>"text/plain", :value=>"Test email body\n\n"}, {:type=>"text/html; charset=UTF-8", :value=>"<!DOCTYPE html>\n<html>\n <head>\n <meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\" />\n <style>\n /* Email styles need to be inline */\n </style>\n </head>\n\n <body>\n <p>Test email body</p>\n<img src=\"cid:5ffdd449d282a_163e2ef9c62c0@server.local.mail\" />\n\n </body>\n</html>\n"}], :attachments=>[{:filename=>"image1.png", :type=>"image/png", :content=>"iVBORw0KGgoAAAANSUhEUgAAALQAAABdCAMAAAA7WLggg==\n"}, {:filename=>"image2.png", :type=>"image/png", :content=>"iVBORw0KGgoAAAANSUhEUgAAAAggg==\n", :content_id=>"5ffdd449d282a_163e2ef9c62c0@server.local.mail"}]}
#=> {:response=>"OK"}
```