Support uploads using the put saver

TiddlyWiki's upload.js saver is old and deprecated so let's see if
we can switch to using the put saver.

Includes:
- A bogus WebDAV header to convince TiddlyWiki that the put
  saver is usable
- A new controller method and route for the "put" saves
- Clear the url from $:/UploadURL when serving a site to make
  sure TW doesn't try to use the upload saver

There's a related PR for TiddlyWiki that exposes the error messages
to the user, see TiddlyWiki/TiddlyWiki5#6589

Issue: #148

rails/app/controllers/tiddlywiki_controller.rb

@@ -7,7 +7,7 @@ class TiddlywikiController < ApplicationController
   before_action :find_site
 
   # TiddlyWiki can't provide the token for saving so we need to skip it
-  skip_before_action :verify_authenticity_token, only: :save
+  skip_before_action :verify_authenticity_token, only: [:upload_save, :put_save]
 
   # Rails wants a token for options requests, which TiddlyWiki similarly can't provide
   skip_before_action :verify_authenticity_token,
@@ -20,6 +20,9 @@ class TiddlywikiController < ApplicationController
   def serve
     return site_not_available unless site_visible?
 
+    # Convince TiddlyWiki it can use the put saver
+    dummy_webdav_header if request.options? && @site.enable_put_saver?
+
     etag_header
 
     # Avoid site download for head or options requests
@@ -92,7 +95,8 @@ def download
     download_html_content(@site.download_content, @site.name)
   end
 
-  def save
+  # Using the "upload" saver
+  def upload_save
     begin
       if site_saveable?
         @site.file_upload(params[:userfile])
@@ -108,6 +112,24 @@ def save
     end
   end
 
+  # Using the "put" saver
+  def put_save
+    begin
+      if site_saveable?
+        @site.file_upload(request.body)
+        @site.increment_save_count
+        head 204
+      else
+        err_message = "If this is your site please log in at #{main_site_url} and try again."
+        render status: 403, plain: err_message
+      end
+    rescue => e
+      # Todo: Should probably give a generic "Save failed!" message, and log the real problem
+      err_message = "#{e.class.name} #{e.message}"
+      render status: 500, plain: err_message
+    end
+  end
+
   private
 
   def update_view_count_and_access_timestamp
@@ -200,4 +222,9 @@ def cors_headers
     response.set_header 'Access-Control-Allow-Headers', 'X-Requested-With'
   end
 
+  # TiddlyWiki just checks if the header exists so the value doesn't matter
+  def dummy_webdav_header
+    response.set_header 'dav', "Dummy WebDAV header to enable TiddlyWiki's PUT saver"
+  end
+
 end

rails/app/models/site.rb

@@ -56,7 +56,8 @@ def looks_valid?
   end
 
   def html_content(signed_in_user: nil)
-    th_file.apply_tiddlyhost_mods(name, signed_in_user: signed_in_user).to_html
+    th_file.apply_tiddlyhost_mods(name,
+      signed_in_user: signed_in_user, enable_put_saver: enable_put_saver).to_html
   end
 
   def json_data(opts={})

rails/config/routes.rb

@@ -29,7 +29,8 @@
     get '/favicon.ico', to: 'tiddlywiki#favicon'
     get '/download', to: 'tiddlywiki#download'
 
-    post '/', to: 'tiddlywiki#save'
+    post '/', to: 'tiddlywiki#upload_save'
+    put '/', to: 'tiddlywiki#put_save'
   end
 
   #

rails/lib/th_file.rb

@@ -38,17 +38,22 @@ def self.from_empty(empty_type)
     from_file(empty_path(empty_type))
   end
 
-  def apply_tiddlyhost_mods(site_name, for_download: false, signed_in_user: nil)
+  def apply_tiddlyhost_mods(site_name, for_download: false, enable_put_saver: false, signed_in_user: nil)
     if is_tw5?
 
-      upload_url = if !for_download
-        # The url for uploads is the same as the site url
-        Settings.subdomain_site_url(site_name)
-      else
-        # Clear $:/UploadURL so the save button in the downloaded file will not try
-        # to use upload.js. It should use another save method, probably download to file.
+      upload_url = if for_download || enable_put_saver
+        # Clear $:/UploadURL for downloads so the save button in the downloaded
+        # file will not try to use upload.js. It should use another save
+        # method, probably download to file.
+        #
         # Todo: Consider if we should do that also when signed_in_user is nil.
+        #
+        # Clear $:/UploadURL when using the put saver otherwise TW will
+        # prioritize the upload saver
         ""
+      else
+        # The url for uploads is the same as the site url
+        Settings.subdomain_site_url(site_name)
       end
 
       if !for_download && signed_in_user
@@ -73,6 +78,7 @@ def apply_tiddlyhost_mods(site_name, for_download: false, signed_in_user: nil)
 
         # Set this otherwise TiddlyWiki won't consider upload.js usable unless there
         # is a username and password present.
+        # (Not needed for put saver but should be harmless.)
         '$:/UploadWithUrlOnly' => 'yes',
 
         # Autosave is nice, but I'm thinking we should start with it off to generate

rails/test/controllers/tiddlywiki_controller_test.rb

@@ -130,7 +130,7 @@ def assert_tid_not_found(url)
         site.th_file.write_tiddlers({'NewTiddler'=>'Hey now'}).to_html)
 
       # Now simulate a save
-      save_site_as_user(user: site.user, site: site, fixture_file: 'index.html')
+      upload_save_site_as_user(user: site.user, site: site, fixture_file: 'index.html')
 
       # Should see these fields are updated
       site.reload
@@ -146,6 +146,35 @@ def assert_tid_not_found(url)
       th_file = fetch_site_as_user(user: site.user, site: site)
       assert_equal 'Hey now', th_file.tiddler_content('NewTiddler')
 
+      if th_file.is_tw5?
+        # Same thing again but using the put saver
+        # (compatible with TW5 only)
+
+        site.update(enable_put_saver: true)
+        prev_blob_key = site.blob.key
+
+        File.write(modified_tw_file,
+          site.th_file.write_tiddlers({'NewTiddler'=>'Hi from put saver'}).to_html)
+
+        put_save_site_as_user(user: site.user, site: site, content_file: modified_tw_file)
+
+        # Should see these fields are updated
+        site.reload
+        assert_not_equal original_blob_key, site.blob.key
+        assert_not_equal prev_blob_key, site.blob.key
+        assert original_size < site.raw_byte_size
+        assert_equal site_name, site.name
+        assert_equal tw_version, site.tw_version
+
+        # Confirm the site has the new tiddler
+        assert_equal "Hi from put saver", site.th_file.tiddler_content('NewTiddler')
+
+        # Confirm it via http get
+        th_file = fetch_site_as_user(user: site.user, site: site)
+        assert_equal 'Hi from put saver', th_file.tiddler_content('NewTiddler')
+
+      end
+
       # Clean up temporary file
       File.delete(modified_tw_file)
     end
@@ -167,7 +196,14 @@ def fetch_site_as_user(user: @user, site: @site, expected_status: 200)
       th_file = ThFile.new(response.body)
 
       # Sanity checks
-      assert_equal site.name, th_file.get_site_name
+      if site.enable_put_saver?
+        # Fixme: get_site_name can't work because $:/UploadURL isn't set
+        #assert_equal site.name, th_file.get_site_name
+        assert_equal '', th_file.tiddler_content('$:/UploadURL') if th_file.is_tw5?
+      else
+        assert_equal site.name, th_file.get_site_name
+        assert_equal site.url, th_file.tiddler_content('$:/UploadURL') if th_file.is_tw5?
+      end
       assert_equal 'Hi there', th_file.tiddler_content('MyTiddler')
       assert_equal 'Bar', th_file.tiddler_content('Foo')
       assert_equal '123', th_file.tiddler_content('Baz')
@@ -183,7 +219,7 @@ def fetch_site_as_user(user: @user, site: @site, expected_status: 200)
     end
   end
 
-  def save_site_as_user(site:, user:, fixture_file:, expected_status: 200)
+  def upload_save_site_as_user(site:, user:, fixture_file:, expected_status: 200)
     host! site.host
     sign_in user
 
@@ -201,4 +237,15 @@ def save_site_as_user(site:, user:, fixture_file:, expected_status: 200)
     # Todo maybe: Is there anything else worth asserting in the headers?
   end
 
+  def put_save_site_as_user(site:, user:, content_file:, expected_status: 204)
+    host! site.host
+    sign_in user
+
+    put '/', params: File.read(content_file),
+      headers: { 'Content-Type' => 'text/html;charset=UTF-8' }
+
+    assert_response expected_status
+    assert_equal '', response.body
+  end
+
 end

rails/test/models/tw_file_test.rb

@@ -60,6 +60,18 @@ class TwFileTest < ActiveSupport::TestCase
       # We can't get the name without $:/UploadURL...
       assert_nil tw.get_site_name
     end
+
+    ThFile.from_empty(:tw5).apply_tiddlyhost_mods('coolsite', enable_put_saver: true).tap do |tw|
+      {
+        '$:/UploadURL' => '',
+        '$:/UploadWithUrlOnly' => 'yes',
+        '$:/config/AutoSave' => 'no',
+
+      }.each do |tiddler_name, expected_content|
+        assert_equal expected_content, tw.tiddler_content(tiddler_name)
+      end
+
+    end
   end
 
   test "tiddlyhost mods for classic" do