How do I pass commentable into mailer? - ruby-on-rails

Question

I have this in the Model:
after_create do |comment|
CommentMailer.comment_email(self).deliver
end
This in CommentMailer:
class CommentMailer < ActionMailer::Base
helper ActionView::Helpers::UrlHelper
include CommentHelper
helper :comment
def comment_email(user, comment, commentable)
mail(to: user.email,
subject: "You have left a comment",
from: "comments#lumeo.com",
bcc: "brian#lumeo.com")
end
end
And this in CommentHelper:
module CommentHelper
def find_commentable
#comment = Comment.find(params[:comment])
params.each do |name, value|
if name =~ /(.+)_id$/
return $1.classify.constantize.find(value)
end
end
nil
end
end
I'm getting this error:
Started POST "/requests/6/comments" for 127.0.0.1 at 2012-11-30 17:28:55 -0800
Processing by CommentsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"R62NH5/EE34FPapEqy7mfpa0wKz18GtSdhH8MGYq2Ec=", "comment"=>{"content"=>"post", "show"=>"true"}, "commit"=>"Create Comment", "request_id"=>"6"}
User Load (0.3ms) SELECT "users".* FROM "users" WHERE "users"."id" = 2 ORDER BY users.created_at DESC LIMIT 1
Request Load (0.3ms) SELECT "requests".* FROM "requests" WHERE "requests"."id" = $1 LIMIT 1 [["id", "6"]]
CACHE (0.0ms) SELECT "requests".* FROM "requests" WHERE "requests"."id" = $1 LIMIT 1 [["id", "6"]]
(0.1ms) BEGIN
SQL (0.4ms) INSERT INTO "comments" ("commentable_id", "commentable_type", "content", "created_at", "show", "updated_at", "user_id") VALUES ($1, $2, $3, $4, $5, $6, $7) RETURNING "id" [["commentable_id", 6], ["commentable_type", "Request"], ["content", "post"], ["created_at", Sat, 01 Dec 2012 01:28:55 UTC +00:00], ["show", true], ["updated_at", Sat, 01 Dec 2012 01:28:55 UTC +00:00], ["user_id", 2]]
(0.2ms) ROLLBACK
Completed 500 Internal Server Error in 136ms
ArgumentError (wrong number of arguments (1 for 3)):
app/mailers/comment_mailer.rb:5:in `comment_email'
app/models/comment.rb:27:in `block in <class:Comment>'
app/controllers/comments_controller.rb:22:in `create'

Answer 1

Looks like simple typos.
Line 7, as noted in the exception:
commentable = #comment.commentable
So, the issues:
You're calling #comment.commentabe, but #comment is nil
Hence the error: undefined method 'commentable' for nil:NilClass
#comment is nil in your mailer method because you're passing it in as comment NOT #comment, yet you're trying to reference it as #comment.
Also, why are you passing in commentable as a parameter, but on line 7 you're setting commentable again - this is redundant? Just use the already available commentable variable that you're passing in as a param. In fact, you seem to be doing this with several variables, yet I can't tell (because you don't show the mailer template) whether or not you're actually using them.
It could be that you could use something simpler like:
So, this should (probably) work:
def comment_email(user, comment, commentable)
mail(to: user.email,
subject: "You have left a comment",
from: "comments#lumeo.com",
bcc: "brian#lumeo.com")
end
If you post your mail template (so I can see what the body of the email looks like) I can help you get the variables into the template.