Config smtp-delivery via url

README.md

@@ -265,6 +265,14 @@ Mail.defaults do
 end
 ```
 
+An url is also accepted for smtp:
+```ruby
+Mail.defaults do
+  # note the URL-encoded userinfo:
+  delivery_method :smtp, url: 'smtps://user%40gmail.com:[email protected]'
+end
+```
+
 
 Exim requires its own delivery manager, and can be used like so:
 

lib/mail/network/delivery_methods/smtp.rb

@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 require 'mail/smtp_envelope'
+require 'mail/utilities'
 
 module Mail
   # == Sending Email with SMTP
@@ -23,6 +24,7 @@ module Mail
   #                              :password             => '<password>',
   #                              :authentication       => 'plain',
   #                              :enable_starttls_auto => true  }
+  #
   #   end
   # 
   # === Sending via GMail
@@ -35,8 +37,20 @@ module Mail
   #                              :password             => '<password>',
   #                              :authentication       => 'plain',
   #                              :enable_starttls_auto => true  }
+  #
+  #     # ...or using the url-attribute (note the URL-encoded userinfo):
+  #     delivery_method :smtp,
+  #        { :url => 'smtps://user%40gmail.com:[email protected]' }
   #   end
   #
+  # === Sending via Fastmail
+  #
+  #   Mail.defaults do
+  #     delivery_method :smtp,
+  #       { :url => 'smtps://user%40fastmail.fm:[email protected]' }
+  #   end
+  #
+  #
   # === Certificate verification
   #
   # When using TLS, some mail servers provide certificates that are self-signed
@@ -74,6 +88,68 @@ module Mail
   # 
   #   mail.deliver!
   class SMTP
+    class UrlResolver
+
+      DEFAULTS = {
+        "smtp" => {
+          :address              => 'localhost',
+          :port                 => 25,
+          :domain               => 'localhost.localdomain',
+          :enable_starttls_auto => true
+        },
+        "smtps" => {
+          :address              => 'localhost',
+          :port                 => 465,
+          :domain               => 'localhost.localdomain',
+          :enable_starttls_auto => false,
+          :tls                  => true
+        }
+      }
+
+      def initialize(url)
+        @uri = url.is_a?(URI) ? url : uri_parser.parse(url)
+        unless DEFAULTS.has_key?(@uri.scheme)
+          raise ArgumentError, "#{url} is not a valid SMTP-url. Required format: smtp(s)://host?domain=sender.org"
+        end
+        @query = uri.query
+      end
+
+      def to_hash
+        config = raw_config
+        config.map { |key, value| config[key] = uri_parser.unescape(value) if value.is_a? String }
+        config
+      end
+
+      private
+        attr_reader :uri
+
+        def raw_config
+          scheme_defaults.merge(query_hash).merge({
+              :address              => uri.host,
+              :port                 => uri.port,
+              :user_name            => uri.user,
+              :password             => uri.password
+          }.delete_if {|_key, value| Utilities.blank?(value) })
+        end
+
+        def uri_parser
+          Utilities.uri_parser
+        end
+
+        def query_hash
+          @query_hash = begin
+            result = Hash[(@query || "").split("&").map { |pair| k,v = pair.split("="); [k.to_sym, v] }]
+            result[:open_timeout] &&= result[:open_timeout].to_i
+            result[:read_timeout] &&= result[:read_timeout].to_i
+            result
+          end
+        end
+
+        def scheme_defaults
+          DEFAULTS[uri.scheme]
+        end
+    end
+
     attr_accessor :settings
 
     DEFAULTS = {
@@ -92,8 +168,13 @@ class SMTP
       :read_timeout         => nil
     }
 
-    def initialize(values)
-      self.settings = DEFAULTS.merge(values)
+    def initialize(config)
+      settings = DEFAULTS
+
+      if config.has_key?(:url)
+        settings = settings.merge(UrlResolver.new(config.delete(:url)).to_hash)
+      end
+      self.settings = settings.merge(config)
     end
 
     def deliver!(mail)

spec/mail/network/delivery_methods/smtp_spec.rb

@@ -25,6 +25,66 @@
     MockSMTP.clear_deliveries
   end
 
+  describe 'settings via url' do
+    def smtp_delivery_settings_for_url(url, options = {})
+      Mail.defaults { delivery_method :smtp, {:url => url}.merge(options) }
+
+      Mail.delivery_method.settings
+    end
+
+    it 'provides smtp defaults' do
+      expect(smtp_delivery_settings_for_url('smtp:///')).to \
+        include(:address              => 'localhost',
+                :port                 => 25,
+                :domain               => 'localhost.localdomain',
+                :enable_starttls_auto => true)
+    end
+
+    it 'provides smtps defaults' do
+      expect(smtp_delivery_settings_for_url('smtps:///')).to \
+        include(:address => 'localhost',
+                :port    => 465,
+                :domain  => 'localhost.localdomain',
+                :tls     => true)
+    end
+
+    it 'allows for all attributes to be set' do
+      url = 'smtp://mailer.org:12345?domain=sender.org&authentication=plain&openssl_verify_mode=peer&tls=true&open_timeout=1&read_timeout=2'
+      expect(smtp_delivery_settings_for_url(url)).to \
+        include(:address              => 'mailer.org',
+                :port                 => 12345,
+                :domain               => 'sender.org',
+                :authentication       => 'plain',
+                :openssl_verify_mode  => 'peer',
+                :tls                  => 'true',
+                :open_timeout         => 1,
+                :read_timeout         => 2)
+    end
+
+    it 'allows for url-attributes to be overriden' do
+      overrides = {:address => 'real-host', :domain => 'real-domain'}
+      expect(smtp_delivery_settings_for_url('smtp://user:pw@host?domain=sender.org', overrides)).to \
+        include(overrides)
+    end
+
+    it 'escapes credentials' do
+      expect(smtp_delivery_settings_for_url('smtps://user%40host:pw-with-%[email protected]')).to \
+        include(:user_name => 'user@host',
+                :password => 'pw-with-/')
+    end
+
+    it 'accepts an URI' do
+      expect(smtp_delivery_settings_for_url(URI.parse('smtps://host'))).to \
+        include(:address => 'host')
+    end
+
+    it 'should raise an error for url without smtp(s) scheme' do
+      expect {
+        smtp_delivery_settings_for_url('foo://host')
+      }.to raise_error(/is not a valid SMTP-url/)
+    end
+  end
+
   describe "general usage" do
     it "dot-stuff unterminated last line of the message" do
       Mail.deliver do