Send an email with Rails

Question

I've been reading up on the ActionMailer, but I'm having real trouble sending an email with ROR3.

I'm trying to follow section 2.1 of this tutorial

When I create a new user, I just get this message:

NameError in UsersController#create

uninitialized constant UsersController::UserMailer

I've had a break from ROR, and now I've found I've forgotten quite a lot!

What are the most likely causes of this error?

My mailer (controller): app/mailers/usermailer.rb:

class Usermailer < ActionMailer::Base
  default from: "from@example.com"

  def welcome_email(user)
    @user = user
    @url = 'http://example.com/login'
    mail(to: @user.email, subject: 'Welcome to my awesome site')
  end
end

My view: app/usermailer/welcome_email.html.erb:

<!DOCTYPE html>
<html>
  <head>
    <meta content='text/html; charset=UTF-8' http-equiv='Content-Type' />
  </head>
  <body>
    <h1>Welcome to example.com, <%= @user.name %></h1>
    <p>
      You have successfully signed up to example.com,
      your username is: <%= @user.login %>.<br/>
    </p>
    <p>
      To login to the site, just follow this link: <%= @url %>.
    </p>
    <p>Thanks for joining and have a great day!</p>
  </body>
</htm>

Not sure what this is classed as. A "view call" in the users controller to the view welcome_email to @user:

   UserMailer.welcome_email(@user).deliver

Here it is in context at app/controllers/users_controller.rb:

class UsersController < ApplicationController
  # GET /users
  # GET /users.json
  def index
    @users = User.all

    respond_to do |format|
      format.html # index.html.erb
      format.json { render json: @users }
    end
  end

  # GET /users/1
  # GET /users/1.json
  def show
    @user = User.find(params[:id])

    respond_to do |format|
      format.html # show.html.erb
      format.json { render json: @user }
    end
  end

  # GET /users/new
  # GET /users/new.json
  def new
    @user = User.new

    respond_to do |format|
      format.html # new.html.erb
      format.json { render json: @user }
    end
  end

  # GET /users/1/edit
  def edit
    @user = User.find(params[:id])
  end

  # POST /users
  # POST /users.json
  def create
    @user = User.new(params[:user])

    respond_to do |format|
      if @user.save

    # send welcome email after save
    UserMailer.welcome_email(@user).deliver

        format.html { redirect_to @user, notice: 'User was successfully created.' }
        format.json { render json: @user, status: :created, location: @user }
      else
        format.html { render action: "new" }
        format.json { render json: @user.errors, status: :unprocessable_entity }
      end
    end
  end

  # PUT /users/1
  # PUT /users/1.json
  def update
    @user = User.find(params[:id])

    respond_to do |format|
      if @user.update_attributes(params[:user])
        format.html { redirect_to @user, notice: 'User was successfully updated.' }
        format.json { head :no_content }
      else
        format.html { render action: "edit" }
        format.json { render json: @user.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /users/1
  # DELETE /users/1.json
  def destroy
    @user = User.find(params[:id])
    @user.destroy

    respond_to do |format|
      format.html { redirect_to users_url }
      format.json { head :no_content }
    end
  end
end

Answer 1 · 2013-08-31T01:37:42Z

August 31, 2013 1:37am

I think you may have mistyped the name of the user mailer class. In the example above it's

class Usermailer < ActionMailer::Base

and when you restarted from scratch you probably now have

class UserMailer < ActionMailer::Base

Typos are usually the first thing to look for when you see an uninitialized constant error. In the example above in your Users controller you have a reference to

    UserMailer.welcome_email(@user).deliver

And the error was saying it didn't know what that was because you had it named as

class Usermailer < ActionMailer::Base

Hope that helps.

-twiz

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Send an email with Rails

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1 Answer

Twiz T

Twiz T

Julian Hurley

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