Testing ActionMailer multipart emails(text and html version) with RSpec - ruby

Question

I'm currently testing my mailers with RSpec, but I've started setting up multipart emails as described in the Rails Guides here: http://guides.rubyonrails.org/action_mailer_basics.html#sending-multipart-emails
I have both mailer templates in text and html formats, but it looks like my tests are only checking the HTML portion. Is there a way to check the text template separately?
Is it only checking the HTML view because it's first in the default order?

Answer 1

To supplement, nilmethod's excellent answer, you can clean up your specs by testing both text and html versions using a shared example group:
spec_helper.rb
def get_message_part (mail, content_type)
mail.body.parts.find { |p| p.content_type.match content_type }.body.raw_source
end
shared_examples_for "multipart email" do
it "generates a multipart message (plain text and html)" do
mail.body.parts.length.should eq(2)
mail.body.parts.collect(&:content_type).should == ["text/plain; charset=UTF-8", "text/html; charset=UTF-8"]
end
end
your_email_spec.rb
let(:mail) { YourMailer.action }
shared_examples_for "your email content" do
it "has some content" do
part.should include("the content")
end
end
it_behaves_like "multipart email"
describe "text version" do
it_behaves_like "your email content" do
let(:part) { get_message_part(mail, /plain/) }
end
end
describe "html version" do
it_behaves_like "your email content" do
let(:part) { get_message_part(mail, /html/) }
end
end

Answer 2

This can be tested with regular expressions.
Finding things in the HTML portion (use #should after this to match):
mail.body.parts.find {|p| p.content_type.match /html/}.body.raw_source
Finding things in the plain text portion (use #should after this to match):
mail.body.parts.find {|p| p.content_type.match /plain/}.body.raw_source
Checking that it is, indeed, generating a multipart message:
it "generates a multipart message (plain text and html)" do
mail.body.parts.length.should == 2
mail.body.parts.collect(&:content_type).should == ["text/html; charset=UTF-8", "text/plain; charset=UTF-8"]
end

Answer 3

To make things even simpler, you can use
message.text_part and
message.html_part
to find the respective parts. This works even for structured multipart/alternative messages with attachments. (Tested on Ruby 1.9.3 with Rails 3.0.14.)
These methods employ some kind of heuristic to find the respective message parts, so if your message has multiple text parts (e.g. as Apple Mail creates them) it might fail to do the "right thing".
This would change the above method to
def body_should_match_regex(mail, regex)
if mail.multipart?
["text", "html"].each do |part|
mail.send("#{part}_part").body.raw_source.should match(regex)
end
else
mail.body.raw_source.should match(regex)
end
end
which works for both plaintext (non-multipart) messages and multipart messages and tests all message bodies against a specific regular expression.
Now, any volunteers to make a "real" RSpec matcher out of this? :) Something like
#mail.bodies_should_match /foobar/
would be a lot nicer ...

Answer 4

If your email has attachments the text and html parts will end be placed in a multipart/alternative part. This is noted on under Sending Emails with Attachments in the Rails 3 Guide.
To handle this, I first simplified the get_message_part method above to:
def get_message_part(mail, content_type)
mail.body.parts.find { |p| p.content_type.match content_type }
end
Then in my test:
multipart = get_message_part(email, /multipart/)
html = get_message_part(multipart, /html/)
html_body = html.body.raw_source
assert_match 'some string', html_body

Answer 5

I have done this way, I found it simpler since the content of both emails is gonna be similar except styles and markup.
context 'When there are no devices' do
it 'makes sure both HTML and text version emails are sent' do
expect(mail.body.parts.count).to eq(2)
# You can even make sure the types of the part are `html` and `text`
end
it 'does not list any lockboxes to be removed in both types emails' do
mail.body.parts.each do |part|
expect(part.body).to include('No devices to remove')
end
end
end