Make environment name and intercept mail customizable

Author: monkbroc

README.md

@@ -87,6 +87,20 @@ MailInterceptor::Interceptor.new({ forward_emails_to: ['intercepted_emails@bigbi
                                                        'qa@bigbinary.com' })
 ```
 
+### Custom environment name
+
+If your staging environment is using the same Rails environment as
+production, you can pass in the the name of the environment and whether
+to intercept mail as options. The default is to use `Rails.env` and
+intercept mail in all environments except production.
+
+```ruby
+MailInterceptor::Interceptor.new({ env_name: ENV["INSTANCE_NAME"],
+                                   intercept_mail?: ENV["INTERCEPT_MAIL"] == '1',
+                                   forward_emails_to: ['intercepted_emails@bigbinary.com',
+                                   'qa@bigbinary.com' })
+```
+
 #### Brought to you by
 
 [![BigBinary logo](http://bigbinary.com/assets/common/logo.png)](http://BigBinary.com)

lib/mail_interceptor.rb

@@ -10,6 +10,8 @@ def initialize options = {}
       @deliver_emails_to = Array.wrap options[:deliver_emails_to]
       @subject_prefix    = options[:subject_prefix] || ''
       @forward_emails_to = options.fetch :forward_emails_to
+      @env_name          = options.fetch :env_name, default_env_name
+      @intercept_mail    = options.fetch :intercept_mail?, default_intercept_mail?
 
       add_env_info_to_subject_prefix
       sanitize_forward_emails_to
@@ -22,8 +24,13 @@ def delivering_email message
 
     private
 
+    attr_reader :env_name
+    def intercept_mail?
+      @intercept_mail
+    end
+
     def normalize_recipients recipients
-      return Array.wrap(recipients) if production?
+      return Array.wrap(recipients) unless intercept_mail?
 
       return forward_emails_to if deliver_emails_to.empty?
 
@@ -45,27 +52,27 @@ def add_subject_prefix message
     def sanitize_forward_emails_to
       self.forward_emails_to = Array.wrap forward_emails_to
 
-      if forward_emails_to_empty? && !production?
+      if forward_emails_to_empty? && intercept_mail?
         raise "forward_emails_to should not be empty"
       end
     end
 
     def add_env_info_to_subject_prefix
       return if subject_prefix.blank?
 
-      _prefix = production? ? subject_prefix : "#{subject_prefix} #{env.upcase}"
+      _prefix = intercept_mail? ? "#{subject_prefix} #{env_name.upcase}" : subject_prefix
       self.subject_prefix = "[#{_prefix}]"
     end
 
     def forward_emails_to_empty?
       Array.wrap(forward_emails_to).reject(&:blank?).empty?
     end
 
-    def production?
-      env.production?
+    def default_intercept_mail?
+      !Rails.env.production?
     end
 
-    def env
+    def default_env_name
       Rails.env
     end
   end

test/mail_interceptor_test.rb

@@ -55,6 +55,18 @@ def test_subject_prefix_in_test
     assert_equal "[wheel TEST] Another Forgot password", @message.subject
   end
 
+  def test_subject_prefix_in_custom_staging
+    stub_env_methods('production')
+    interceptor = ::MailInterceptor::Interceptor.new env_name: 'staging',
+                                                     intercept_mail?: true,
+                                                     forward_emails_to: 'test@example.com',
+                                                     subject_prefix: 'wheel'
+    @message.subject = 'Forgot password'
+
+    interceptor.delivering_email @message
+    assert_equal "[wheel STAGING] Forgot password", @message.subject
+  end
+
   def test_subject_prefix_in_production
     stub_env_methods('production')
     interceptor = ::MailInterceptor::Interceptor.new forward_emails_to: 'test@example.com',
@@ -93,7 +105,7 @@ def test_error_if_forward_emails_to_is_empty
   private
 
   def stub_env_methods(env)
-    ::MailInterceptor::Interceptor.any_instance.stubs(:env).returns(env)
-    ::MailInterceptor::Interceptor.any_instance.stubs(:production?).returns(env == 'production')
+    ::MailInterceptor::Interceptor.any_instance.stubs(:default_env_name).returns(env)
+    ::MailInterceptor::Interceptor.any_instance.stubs(:default_intercept_mail?).returns(env != 'production')
   end
 end