The preview server can now serve over HTTPS using the --https flag. It will use an automatic self-signed cert which can be overridden using --ssl_certificate and --ssl_private_key. These settings can also be set in config.rb.

CHANGELOG.md

@@ -33,3 +33,4 @@ master
 * Remove deprecated `request` instance
 * Remove old module-style extension support
 * Placed all `config.rb` evaluation inside the `ConfigContext` class
+* The preview server can now serve over HTTPS using the `--https` flag. It will use an automatic self-signed cert which can be overridden using `--ssl_certificate` and `--ssl_private_key`. These settings can also be set in `config.rb`

middleman-core/lib/middleman-core/application.rb

@@ -89,6 +89,18 @@ module Middleman
     # @return [Fixnum]
     config.define_setting :port, 4567, 'The preview server port'
 
+    # Whether to serve the preview server over HTTPS.
+    # @return [Boolean]
+    config.define_setting :https, false, 'Serve the preview server over SSL/TLS'
+
+    # The (optional) path to the SSL cert to use for the preview server.
+    # @return [String]
+    config.define_setting :ssl_certificate, nil, 'Path to an X.509 certificate to use for the preview server'
+
+    # The (optional) private key for the certificate in :ssl_certificate.
+    # @return [String]
+    config.define_setting :ssl_private_key, nil, "Path to an RSA private key for the preview server's certificate"
+
     # Name of the source directory
     # @return [String]
     config.define_setting :source, 'source', 'Name of the source directory'

middleman-core/lib/middleman-core/cli/server.rb

@@ -18,6 +18,13 @@ module Middleman::Cli
     method_option :port,
                   aliases: '-p',
                   desc: 'The port Middleman will listen on'
+    method_option :https,
+                  type: :boolean,
+                  desc: 'Serve the preview server over SSL/TLS'
+    method_option :ssl_certificate,
+                  desc: 'Path to an X.509 certificate to use for the preview server'
+    method_option :ssl_private_key,
+                  desc: "Path to an RSA private key for the preview server's certificate"
     method_option :verbose,
                   type: :boolean,
                   default: false,
@@ -63,6 +70,9 @@ module Middleman::Cli
       params = {
         port: options['port'],
         host: options['host'],
+        https: options['https'],
+        ssl_certificate: options['ssl_certificate'],
+        ssl_private_key: options['ssl_private_key'],
         environment: options['environment'],
         debug: options['verbose'],
         instrumenting: options['instrument'],

middleman-core/lib/middleman-core/preview_server.rb

@@ -1,4 +1,6 @@
 require 'webrick'
+require 'webrick/https'
+require 'openssl'
 require 'middleman-core/meta_pages'
 require 'middleman-core/logger'
 require 'middleman-core/rack'
@@ -9,9 +11,13 @@ module Middleman
     class << self
       extend Forwardable
 
-      attr_reader :app, :host, :port
+      attr_reader :app, :host, :port, :ssl_certificate, :ssl_private_key
       def_delegator :app, :logger
 
+      def https?
+        @https
+      end
+
       # Start an instance of Middleman::Application
       # @return [void]
       def start(opts={})
@@ -105,6 +111,8 @@ module Middleman
 
           config[:host] = opts[:host] if opts[:host]
           config[:port] = opts[:port] if opts[:port]
+          config[:ssl_certificate] = opts[:ssl_certificate] if opts[:ssl_certificate]
+          config[:ssl_private_key] = opts[:ssl_private_key] if opts[:ssl_private_key]
 
           ready do
             match_against = [
@@ -123,6 +131,10 @@ module Middleman
 
         @host = app.config[:host]
         @port = app.config[:port]
+        @https = @app.config[:https]
+
+        @ssl_certificate = @app.config[:ssl_certificate]
+        @ssl_private_key = @app.config[:ssl_private_key]
 
         app.files.on_change :reload do
           $mm_reload = true
@@ -163,6 +175,22 @@ module Middleman
           DoNotReverseLookup: true
         }
 
+        if https?
+          http_opts[:SSLEnable] = true
+
+          if ssl_certificate || ssl_private_key
+            raise "You must provide both :ssl_certificate and :ssl_private_key" unless ssl_private_key && ssl_certificate
+            http_opts[:SSLCertificate] = OpenSSL::X509::Certificate.new File.read ssl_certificate
+            http_opts[:SSLPrivateKey] = OpenSSL::PKey::RSA.new File.read ssl_private_key
+          else
+            # use a generated self-signed cert
+            http_opts[:SSLCertName] = [
+                                       %w(CN localhost),
+                                       %w(CN #{host})
+                                      ].uniq
+          end
+        end
+
         if is_logging
           http_opts[:Logger] = FilteredWebrickLog.new
         else
@@ -203,7 +231,8 @@ module Middleman
       # @return [URI]
       def uri
         host = (@host == '0.0.0.0') ? 'localhost' : @host
-        URI("http://#{host}:#{@port}")
+        scheme = https? ? 'https' : 'http'
+        URI("#{scheme}://#{host}:#{@port}")
       end
     end