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Diffstat (limited to 'guides/source/action_mailer_basics.md')
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1 files changed, 123 insertions, 36 deletions
diff --git a/guides/source/action_mailer_basics.md b/guides/source/action_mailer_basics.md index 9ad9319255..4800cece82 100644 --- a/guides/source/action_mailer_basics.md +++ b/guides/source/action_mailer_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.** + Action Mailer Basics ==================== @@ -35,10 +37,26 @@ views. ```bash $ bin/rails generate mailer UserMailer create app/mailers/user_mailer.rb +create app/mailers/application_mailer.rb invoke erb create app/views/user_mailer +create app/views/layouts/mailer.text.erb +create app/views/layouts/mailer.html.erb invoke test_unit create test/mailers/user_mailer_test.rb +create test/mailers/previews/user_mailer_preview.rb +``` + +```ruby +# app/mailers/application_mailer.rb +class ApplicationMailer < ActionMailer::Base + default from: "from@example.com" + layout 'mailer' +end + +# app/mailers/user_mailer.rb +class UserMailer < ApplicationMailer +end ``` As you can see, you can generate mailers just like you use other generators with @@ -63,8 +81,7 @@ delivered via email. `app/mailers/user_mailer.rb` contains an empty mailer: ```ruby -class UserMailer < ActionMailer::Base - default from: 'from@example.com' +class UserMailer < ApplicationMailer end ``` @@ -72,7 +89,7 @@ Let's add a method called `welcome_email`, that will send an email to the user's registered email address: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer default from: 'notifications@example.com' def welcome_email(user) @@ -159,7 +176,10 @@ $ bin/rake db:migrate Now that we have a user model to play with, we will just edit the `app/controllers/users_controller.rb` make it instruct the `UserMailer` to deliver an email to the newly created user by editing the create action and inserting a -call to `UserMailer.welcome_email` right after the user is successfully saved: +call to `UserMailer.welcome_email` right after the user is successfully saved. + +Action Mailer is nicely integrated with Active Job so you can send emails outside +of the request-response cycle, so the user doesn't have to wait on it: ```ruby class UsersController < ApplicationController @@ -171,7 +191,7 @@ class UsersController < ApplicationController respond_to do |format| if @user.save # Tell the UserMailer to send a welcome email after save - UserMailer.welcome_email(@user).deliver + UserMailer.welcome_email(@user).deliver_later format.html { redirect_to(@user, notice: 'User was successfully created.') } format.json { render json: @user, status: :created, location: @user } @@ -184,8 +204,29 @@ class UsersController < ApplicationController end ``` -The method `welcome_email` returns a `Mail::Message` object which can then just -be told `deliver` to send itself out. +NOTE: Active Job's default behavior is to execute jobs ':inline'. So, you can use +`deliver_later` now to send emails, and when you later decide to start sending +them from a background job, you'll only need to set up Active Job to use a queueing +backend (Sidekiq, Resque, etc). + +If you want to send emails right away (from a cronjob for example) just call +`deliver_now`: + +```ruby +class SendWeeklySummary + def run + User.find_each do |user| + UserMailer.weekly_summary(user).deliver_now + end + end +end +``` + +The method `welcome_email` returns a `ActionMailer::MessageDelivery` object which +can then just be told `deliver_now` or `deliver_later` to send itself out. The +`ActionMailer::MessageDelivery` object is just a wrapper around a `Mail::Message`. If +you want to inspect, alter or do anything else with the `Mail::Message` object you can +access it with the `message` method on the `ActionMailer::MessageDelivery` object. ### Auto encoding header values @@ -274,8 +315,7 @@ Action Mailer 3.0 makes inline attachments, which involved a lot of hacking in p ```html+erb <p>Hello there, this is our image</p> - <%= image_tag attachments['image.jpg'].url, alt: 'My Photo', - class: 'photos' %> + <%= image_tag attachments['image.jpg'].url, alt: 'My Photo', class: 'photos' %> ``` #### Sending Email To Multiple Recipients @@ -286,7 +326,7 @@ key. The list of emails can be an array of email addresses or a single string with the addresses separated by commas. ```ruby -class AdminMailer < ActionMailer::Base +class AdminMailer < ApplicationMailer default to: Proc.new { Admin.pluck(:email) }, from: 'notification@example.com' @@ -304,7 +344,7 @@ The same format can be used to set carbon copy (Cc:) and blind carbon copy Sometimes you wish to show the name of the person instead of just their email address when they receive the email. The trick to doing that is to format the -email address in the format `"Full Name <email>"`. +email address in the format `"Full Name" <email>`. ```ruby def welcome_email(user) @@ -325,7 +365,7 @@ for the HTML version and `welcome_email.text.erb` for the plain text version. To change the default mailer view for your action you do something like: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer default from: 'notifications@example.com' def welcome_email(user) @@ -347,7 +387,7 @@ If you want more flexibility you can also pass a block and render specific templates or even render inline or text without using a template file: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer default from: 'notifications@example.com' def welcome_email(user) @@ -377,7 +417,7 @@ layout. In order to use a different file, call `layout` in your mailer: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer layout 'awesome' # use awesome.(html|text).erb as the layout end ``` @@ -389,7 +429,7 @@ You can also pass in a `layout: 'layout_name'` option to the render call inside the format block to specify different layouts for different formats: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def welcome_email(user) mail(to: user.email) do |format| format.html { render layout: 'my_layout' } @@ -402,6 +442,39 @@ end Will render the HTML part using the `my_layout.html.erb` file and the text part with the usual `user_mailer.text.erb` file if it exists. +### Previewing Emails + +Action Mailer previews provide a way to see how emails look by visiting a +special URL that renders them. In the above example, the preview class for +`UserMailer` should be named `UserMailerPreview` and located in +`test/mailers/previews/user_mailer_preview.rb`. To see the preview of +`welcome_email`, implement a method that has the same name and call +`UserMailer.welcome_email`: + +```ruby +class UserMailerPreview < ActionMailer::Preview + def welcome_email + UserMailer.welcome_email(User.first) + end +end +``` + +Then the preview will be available in <http://localhost:3000/rails/mailers/user_mailer/welcome_email>. + +If you change something in `app/views/user_mailer/welcome_email.html.erb` +or the mailer itself, it'll automatically reload and render it so you can +visually see the new style instantly. A list of previews are also available +in <http://localhost:3000/rails/mailers>. + +By default, these preview classes live in `test/mailers/previews`. +This can be configured using the `preview_path` option. For example, if you +want to change it to `lib/mailer_previews`, you can configure it in +`config/application.rb`: + +```ruby +config.action_mailer.preview_path = "#{Rails.root}/lib/mailer_previews" +``` + ### Generating URLs in Action Mailer Views Unlike controllers, the mailer instance doesn't have any context about the @@ -430,18 +503,9 @@ You will need to use: By using the full URL, your links will now work in your emails. -#### generating URLs with `url_for` +#### Generating URLs with `url_for` -You need to pass the `only_path: false` option when using `url_for`. This will -ensure that absolute URLs are generated because the `url_for` view helper will, -by default, generate relative URLs when a `:host` option isn't explicitly -provided. - -```erb -<%= url_for(controller: 'welcome', - action: 'greeting', - only_path: false) %> -``` +`url_for` generate full URL by default in templates. If you did not configure the `:host` option globally make sure to pass it to `url_for`. @@ -453,10 +517,7 @@ If you did not configure the `:host` option globally make sure to pass it to action: 'greeting') %> ``` -NOTE: When you explicitly pass the `:host` Rails will always generate absolute -URLs, so there is no need to pass `only_path: false`. - -#### generating URLs with named routes +#### Generating URLs with Named Routes Email clients have no web context and so paths have no base URL to form complete web addresses. Thus, you should always use the "_url" variant of named route @@ -469,6 +530,27 @@ url helper. <%= user_url(@user, host: 'example.com') %> ``` +NOTE: non-`GET` links require [jQuery UJS](https://github.com/rails/jquery-ujs) +and won't work in mailer templates. They will result in normal `GET` requests. + +### Adding images in Action Mailer Views + +Unlike controllers, the mailer instance doesn't have any context about the +incoming request so you'll need to provide the `:asset_host` parameter yourself. + +As the `:asset_host` usually is consistent across the application you can +configure it globally in config/application.rb: + +```ruby +config.action_mailer.asset_host = 'http://example.com' +``` + +Now you can display an image inside your email. + +```ruby +<%= image_tag 'image.jpg' %> +``` + ### Sending Multipart Emails Action Mailer will automatically send multipart emails if you have different @@ -487,7 +569,7 @@ while delivering emails, you can do this using `delivery_method_options` in the mailer action. ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def welcome_email(user, company) @user = user @url = user_url(@user) @@ -509,7 +591,7 @@ option. In such cases don't forget to add the `:content_type` option. Rails will default to `text/plain` otherwise. ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def welcome_email(user, email_body) mail(to: user.email, body: email_body, @@ -539,7 +621,7 @@ mailer, and pass the email object to the mailer `receive` instance method. Here's an example: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def receive(email) page = Page.find_by(address: email.to.first) page.emails.create( @@ -575,7 +657,7 @@ Action Mailer allows for you to specify a `before_action`, `after_action` and using instance variables set in your mailer action. ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer after_action :set_delivery_options, :prevent_delivery_to_guests, :set_business_headers @@ -632,7 +714,7 @@ files (environment.rb, production.rb, etc...) | Configuration | Description | |---------------|-------------| |`logger`|Generates information on the mailing run if available. Can be set to `nil` for no logging. Compatible with both Ruby's own `Logger` and `Log4r` loggers.| -|`smtp_settings`|Allows detailed configuration for `:smtp` delivery method:<ul><li>`:address` - Allows you to use a remote mail server. Just change it from its default `"localhost"` setting.</li><li>`:port` - On the off chance that your mail server doesn't run on port 25, you can change it.</li><li>`:domain` - If you need to specify a HELO domain, you can do it here.</li><li>`:user_name` - If your mail server requires authentication, set the username in this setting.</li><li>`:password` - If your mail server requires authentication, set the password in this setting.</li><li>`:authentication` - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of `:plain`, `:login`, `:cram_md5`.</li><li>`:enable_starttls_auto` - Set this to `false` if there is a problem with your server certificate that you cannot resolve.</li></ul>| +|`smtp_settings`|Allows detailed configuration for `:smtp` delivery method:<ul><li>`:address` - Allows you to use a remote mail server. Just change it from its default `"localhost"` setting.</li><li>`:port` - On the off chance that your mail server doesn't run on port 25, you can change it.</li><li>`:domain` - If you need to specify a HELO domain, you can do it here.</li><li>`:user_name` - If your mail server requires authentication, set the username in this setting.</li><li>`:password` - If your mail server requires authentication, set the password in this setting.</li><li>`:authentication` - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of `:plain` (will send the password in the clear), `:login` (will send password Base64 encoded) or `:cram_md5` (combines a Challenge/Response mechanism to exchange information and a cryptographic Message Digest 5 algorithm to hash important information)</li><li>`:enable_starttls_auto` - Detects if STARTTLS is enabled in your SMTP server and starts to use it. Defaults to `true`.</li><li>`:openssl_verify_mode` - When using TLS, you can set how OpenSSL checks the certificate. This is really useful if you need to validate a self-signed and/or a wildcard certificate. You can use the name of an OpenSSL verify constant ('none', 'peer', 'client_once', 'fail_if_no_peer_cert') or directly the constant (`OpenSSL::SSL::VERIFY_NONE`, `OpenSSL::SSL::VERIFY_PEER`, ...).</li></ul>| |`sendmail_settings`|Allows you to override options for the `:sendmail` delivery method.<ul><li>`:location` - The location of the sendmail executable. Defaults to `/usr/sbin/sendmail`.</li><li>`:arguments` - The command line arguments to be passed to sendmail. Defaults to `-i -t`.</li></ul>| |`raise_delivery_errors`|Whether or not errors should be raised if the email fails to be delivered. This only works if the external email server is configured for immediate delivery.| |`delivery_method`|Defines a delivery method. Possible values are:<ul><li>`:smtp` (default), can be configured by using `config.action_mailer.smtp_settings`.</li><li>`:sendmail`, can be configured by using `config.action_mailer.sendmail_settings`.</li><li>`:file`: save emails to files; can be configured by using `config.action_mailer.file_settings`.</li><li>`:test`: save emails to `ActionMailer::Base.deliveries` array.</li></ul>See [API docs](http://api.rubyonrails.org/classes/ActionMailer/Base.html) for more info.| @@ -677,6 +759,9 @@ config.action_mailer.smtp_settings = { authentication: 'plain', enable_starttls_auto: true } ``` +Note: As of July 15, 2014, Google increased [its security measures](https://support.google.com/accounts/answer/6010255) and now blocks attempts from apps it deems less secure. +You can change your gmail settings [here](https://www.google.com/settings/security/lesssecureapps) to allow the attempts or +use another ESP to send email by replacing 'smtp.gmail.com' above with the address of your provider. Mailer Testing -------------- @@ -705,7 +790,9 @@ Mailer framework. You can do this in an initializer file `config/initializers/sandbox_email_interceptor.rb` ```ruby -ActionMailer::Base.register_interceptor(SandboxEmailInterceptor) if Rails.env.staging? +if Rails.env.staging? + ActionMailer::Base.register_interceptor(SandboxEmailInterceptor) +end ``` NOTE: The example above uses a custom environment called "staging" for a |