[webui] avoid hanging live log page, when the worker allows TCP conne…

…ct, but does not deliver data

src/api/app/controllers/webui/package_controller.rb

@@ -766,20 +766,21 @@ def live_build_log
     end
     @arch = params[:arch]
     @repo = params[:repository]
+    @offset = 0
 
     set_job_status
+  end
 
+  def set_initial_offset
+    # Do not start at the beginning long time ago
     begin
       size = get_size_of_log(@project, @package, @repo, @arch)
       logger.debug('log size is %d' % size)
       @offset = size - 32 * 1024
       @offset = 0 if @offset < 0
-      @initiallog = get_log_chunk( @project, @package, @repo, @arch, @offset, size)
     rescue => e
       logger.error "Got #{e.class}: #{e.message}; returning empty log."
-      @initiallog = ''
     end
-    @offset = (@offset || 0) + ActiveXML::backend.last_body_length
   end
 
   def update_build_log
@@ -794,6 +795,8 @@ def update_build_log
     @finished = false
     @maxsize = 1024 * 64
 
+    set_initial_offset if @offset == 0
+
     begin
       @log_chunk = get_log_chunk( @project, @package, @repo, @arch, @offset, @offset + @maxsize)
 

src/api/app/views/webui/package/live_build_log.html.erb

@@ -22,10 +22,10 @@
      data-url="<%= url_for(action: :update_build_log,
 		   package: @package, project: @project,
 		   arch: @arch, repository: @repo) %>">
-  <pre id="log_space"><%= raw @initiallog %></pre>
+  <pre id="log_space"></pre>
 </div>
 
-<% if not @initiallog.empty? %>
+<% if not @workerid %>
   <%= render :partial => "live_log_controls" %>
 <% end %>