消息中的NoMethodError #index - nil的未定义方法`name'：NilClass

Question

我没有触及任何与Messages控制器，模型或视图相关的内容，但是我在工作正常之后收到此错误

这是控制器

class MessagesController < ApplicationController
      before_filter :set_user
      before_filter :current_user
      before_filter :ensure_current_user

    def index
    if params[:mailbox] == "sent"
      @messages = @user.sent_messages
    else
      @messages = @user.received_messages
    end
 end

这是视图

  <h2>Inbox (<%= current_user.unread_message_count %>)</h2>
<table>
    <tr>
        <th>Delete?</th>
        <th>Subject</th>
        <th>Sender</th>
        <th>Sent</th>
    </tr><br>
    <% if @messages.size == 0 %>
        <tr>
            <td colspan="4">
                <center>No messages
            </td>
        </tr>
    <% else %><br>
        <% for message in @messages %>
            <tr>
                <td><%= check_box_tag "delete[]", message.id %></td>
                <td>
                    <% if message.message_read? %>
                      <%= link_to h(message.subject), user_message_path(@user, message) %>
                    <% else %>
                      <%= link_to "#{h(message.subject)} (unread)", user_message_path(@user, message) %>
                    <% end %>
                </td>
                <td><%= link_to h(message.sender.name), user_path(message.sender) %></td>
            <td><%=h message.created_at.to_s(:long) %></td>
            </tr>
        <% end %>
        <tr>
            <td colspan="4">
                <%= submit_tag "Delete" %>
            </td>
        </tr>
    <% end %>
</table>
<%= link_to "Sent", user_messages_path(@user, :mailbox => :sent)%> |
<%= link_to "Compose", new_user_message_path(@user)%>

导致错误的行是

<td><%= link_to h(message.sender.name), user_path(message.sender) %></td>

错误消息是

NoMethodError in Messages#index
undefined method `name' for nil:NilClass

如果这有帮助

，这是完整的跟踪

app/views/messages/_inbox.html.erb:26:in `block in _app_views_messages__inbox_html_erb__643493877_49932840'
activerecord (3.2.3) lib/active_record/associations/collection_proxy.rb:89:in `each'
activerecord (3.2.3) lib/active_record/associations/collection_proxy.rb:89:in `method_missing'
app/views/messages/_inbox.html.erb:16:in `_app_views_messages__inbox_html_erb__643493877_49932840'
actionpack (3.2.3) lib/action_view/template.rb:143:in `block in render'
activesupport (3.2.3) lib/active_support/notifications.rb:125:in `instrument'
actionpack (3.2.3) lib/action_view/template.rb:141:in `render'
actionpack (3.2.3) lib/action_view/renderer/partial_renderer.rb:265:in `render_partial'
actionpack (3.2.3) lib/action_view/renderer/partial_renderer.rb:238:in `block in render'
actionpack (3.2.3) lib/action_view/renderer/abstract_renderer.rb:38:in `block in instrument'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.3) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.3) lib/action_view/renderer/abstract_renderer.rb:38:in `instrument'
actionpack (3.2.3) lib/action_view/renderer/partial_renderer.rb:237:in `render'
actionpack (3.2.3) lib/action_view/renderer/renderer.rb:41:in `render_partial'
actionpack (3.2.3) lib/action_view/renderer/renderer.rb:15:in `render'
actionpack (3.2.3) lib/action_view/helpers/rendering_helper.rb:24:in `render'
app/views/messages/index.html.erb:5:in `block in _app_views_messages_index_html_erb___119642823_49752672'
actionpack (3.2.3) lib/action_view/helpers/capture_helper.rb:40:in `block in capture'
actionpack (3.2.3) lib/action_view/helpers/capture_helper.rb:187:in `with_output_buffer'
actionpack (3.2.3) lib/action_view/helpers/capture_helper.rb:40:in `capture'
actionpack (3.2.3) lib/action_view/helpers/form_tag_helper.rb:662:in `form_tag_in_block'
actionpack (3.2.3) lib/action_view/helpers/form_tag_helper.rb:70:in `form_tag'
app/views/messages/index.html.erb:1:in `_app_views_messages_index_html_erb___119642823_49752672'
actionpack (3.2.3) lib/action_view/template.rb:143:in `block in render'
activesupport (3.2.3) lib/active_support/notifications.rb:125:in `instrument'
actionpack (3.2.3) lib/action_view/template.rb:141:in `render'
actionpack (3.2.3) lib/action_view/renderer/template_renderer.rb:47:in `block (2 levels) in render_template'
actionpack (3.2.3) lib/action_view/renderer/abstract_renderer.rb:38:in `block in instrument'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.3) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.3) lib/action_view/renderer/abstract_renderer.rb:38:in `instrument'
actionpack (3.2.3) lib/action_view/renderer/template_renderer.rb:46:in `block in render_template'
actionpack (3.2.3) lib/action_view/renderer/template_renderer.rb:54:in `render_with_layout'
actionpack (3.2.3) lib/action_view/renderer/template_renderer.rb:45:in `render_template'
actionpack (3.2.3) lib/action_view/renderer/template_renderer.rb:18:in `render'
actionpack (3.2.3) lib/action_view/renderer/renderer.rb:36:in `render_template'
actionpack (3.2.3) lib/action_view/renderer/renderer.rb:17:in `render'
actionpack (3.2.3) lib/abstract_controller/rendering.rb:110:in `_render_template'
actionpack (3.2.3) lib/action_controller/metal/streaming.rb:225:in `_render_template'
actionpack (3.2.3) lib/abstract_controller/rendering.rb:103:in `render_to_body'
actionpack (3.2.3) lib/action_controller/metal/renderers.rb:28:in `render_to_body'
actionpack (3.2.3) lib/action_controller/metal/compatibility.rb:50:in `render_to_body'
actionpack (3.2.3) lib/abstract_controller/rendering.rb:88:in `render'
actionpack (3.2.3) lib/action_controller/metal/rendering.rb:16:in `render'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:40:in `block (2 levels) in render'
activesupport (3.2.3) lib/active_support/core_ext/benchmark.rb:5:in `block in ms'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/benchmark.rb:295:in `realtime'
activesupport (3.2.3) lib/active_support/core_ext/benchmark.rb:5:in `ms'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:40:in `block in render'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:83:in `cleanup_view_runtime'
activerecord (3.2.3) lib/active_record/railties/controller_runtime.rb:24:in `cleanup_view_runtime'
sunspot_rails (2.0.0) lib/sunspot/rails/railties/controller_runtime.rb:15:in `cleanup_view_runtime'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:39:in `render'
actionpack (3.2.3) lib/action_controller/metal/implicit_render.rb:10:in `default_render'
actionpack (3.2.3) lib/action_controller/metal/implicit_render.rb:5:in `send_action'
actionpack (3.2.3) lib/abstract_controller/base.rb:167:in `process_action'
actionpack (3.2.3) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (3.2.3) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (3.2.3) lib/active_support/callbacks.rb:469:in `_run__571822877__process_action__113176952__callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.3) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.3) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.2.3) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.3) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
actionpack (3.2.3) lib/action_controller/metal/params_wrapper.rb:205:in `process_action'
activerecord (3.2.3) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (3.2.3) lib/abstract_controller/base.rb:121:in `process'
actionpack (3.2.3) lib/abstract_controller/rendering.rb:45:in `process'
actionpack (3.2.3) lib/action_controller/metal.rb:203:in `dispatch'
actionpack (3.2.3) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.2.3) lib/action_controller/metal.rb:246:in `block in action'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:73:in `call'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:36:in `call'
journey (1.0.4) lib/journey/router.rb:68:in `block in call'
journey (1.0.4) lib/journey/router.rb:56:in `each'
journey (1.0.4) lib/journey/router.rb:56:in `call'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:600:in `call'
omniauth (1.1.4) lib/omniauth/strategy.rb:184:in `call!'
omniauth (1.1.4) lib/omniauth/strategy.rb:164:in `call'
omniauth (1.1.4) lib/omniauth/builder.rb:49:in `call'
warden (1.2.1) lib/warden/manager.rb:35:in `block in call'
warden (1.2.1) lib/warden/manager.rb:34:in `catch'
warden (1.2.1) lib/warden/manager.rb:34:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
rack (1.4.5) lib/rack/etag.rb:23:in `call'
rack (1.4.5) lib/rack/conditionalget.rb:25:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/head.rb:14:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/flash.rb:242:in `call'
rack (1.4.5) lib/rack/session/abstract/id.rb:210:in `context'
rack (1.4.5) lib/rack/session/abstract/id.rb:205:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/cookies.rb:338:in `call'
activerecord (3.2.3) lib/active_record/query_cache.rb:64:in `call'
activerecord (3.2.3) lib/active_record/connection_adapters/abstract/connection_pool.rb:467:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `_run__958820258__call__588161715__callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.3) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.3) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/reloader.rb:65:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.3) lib/rails/rack/logger.rb:26:in `call_app'
railties (3.2.3) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.5) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.5) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.3) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.5) lib/rack/lock.rb:15:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/static.rb:62:in `call'
railties (3.2.3) lib/rails/engine.rb:479:in `call'
railties (3.2.3) lib/rails/application.rb:220:in `call'
rack (1.4.5) lib/rack/content_length.rb:14:in `call'
railties (3.2.3) lib/rails/rack/log_tailer.rb:14:in `call'
rack (1.4.5) lib/rack/handler/webrick.rb:59:in `service'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/webrick/httpserver.rb:138:in `service'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/webrick/httpserver.rb:94:in `run'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/webrick/server.rb:191:in `block in start_thread'

这是数据库中的消息表

create_table "messages", :force => true do |t|
    t.integer   "sender_id"
    t.integer   "recipient_id"
    t.boolean   "sender_deleted",    :default => false
    t.boolean   "recipient_deleted", :default => false
    t.string    "subject"
    t.text      "body"
    t.timestamp "read_at"
    t.timestamp "created_at",                           :null => false
    t.timestamp "updated_at",                           :null => false
  end

我真的很感激帮助。

由于

Answer 1

您的代码似乎没有问题。我认为问题在于数据。有些数据没有sender_id（sender_id为NULL）。

您是否尝试清除消息数据？