pengzhaoqing / courseselect Goto Github PK

C:\Users\tt\Documents\GitHub [master +0 ~1 -1 !]> git push origin master
To https://github.com/tttrzpt/CourseSelect.git
 ! [rejected]        master -> master (non-fast-forward)
error: failed to push some refs to 'https://github.com/tttrzpt/CourseSelect.git'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.
C:\Users\tt\Documents\GitHub [master +0 ~1 -1 !]> git pull origin master
From https://github.com/tttrzpt/CourseSelect
 * branch            master     -> FETCH_HEAD
 * [new branch]      master     -> origin/master
fatal: refusing to merge unrelated histories
C:\Users\tt\Documents\GitHub [master +0 ~1 -1 !]> git remote -v
origin  https://github.com/tttrzpt/CourseSelect.git (fetch)
origin  https://github.com/tttrzpt/CourseSelect.git (push)
C:\Users\tt\Documents\GitHub [master +0 ~1 -1 !]> git push origin master
To https://github.com/tttrzpt/CourseSelect.git
 ! [rejected]        master -> master (non-fast-forward)
error: failed to push some refs to 'https://github.com/tttrzpt/CourseSelect.git'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

    t.datetime "created_at",                    null: false
    t.datetime "updated_at",                    null: false
    t.boolean  "opencourse",    default: false

def list
    @openedcourses=Array.new
    @course=Course.all
    @course=@course-current_user.courses
    @course.each do |course|
      if course.opencourse then
        @[email protected](course)
      end
    end
    @course=@openedcourses
  end

 def open
    @course=Course.find_by_id(params[:id])
    @course.opencourse=true
    redirect_to courses_path, flash: {:success => "已经成功开启该课程:#{ @course.name}"}
  end

<% if teacher_logged_in? %>
                      <td><%= link_to "编辑", edit_course_url(course), class: 'btn btn-xs btn-info' %></td>
                      <td><%= link_to "开课", open_course_url(course), class: 'btn btn-xs btn-info' %></td>

Bundler::GemspecError: Could not read gem at /home/stormand/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/cache/sdoc-0.4.1.gem. It may be corrupted.
An error occurred while installing sdoc (0.4.1), and Bundler cannot continue.
Make sure that `gem install sdoc -v '0.4.1'` succeeds before bundling.

ERROR:  Error installing sdoc:
        invalid gem: package is corrupt, exception while verifying: undefined method `size' for nil:NilClass (NoMethodError) in /home/stormand/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/cache/sdoc-0.4.1.gem

~/workspace/CourseSelect/ (master) $ bundle install


Fetching gem metadata from https://gems.ruby-china.org/...........
Fetching version metadata from https://gems.ruby-china.org/..
Using rake 11.2.2
Using i18n 0.7.0
Using json 1.8.3
Using minitest 5.9.0
Using thread_safe 0.3.5
Using builder 3.2.2
Using erubis 2.7.0
Using mini_portile2 2.1.0
Using pkg-config 1.1.7
Using rack 1.6.4
Using mime-types-data 3.2016.0521
Using arel 6.0.3
Using execjs 2.7.0
Using bcrypt 3.1.11
Using debug_inspector 0.0.2
Using sass 3.4.22
Using byebug 9.0.5
Using coffee-script-source 1.10.0
Using thor 0.19.1
Using concurrent-ruby 1.0.2
Using tilt 2.0.5
Using multi_json 1.12.1
Using nested_form 0.3.2
Using pg 0.18.4
Using bundler 1.13.2
Using rails_serve_static_assets 0.0.5
Using rails_stdout_logging 0.0.5
Using remotipart 1.2.1
Using safe_yaml 1.0.4
Using spring 1.7.2
Using turbolinks-source 5.0.0
Using faker 1.6.3
Using rdoc 4.2.2
Using tzinfo 1.2.2
Installing nokogiri 1.6.8 with native extensions
Using rack-test 0.6.3
Using mime-types 3.1
Using autoprefixer-rails 6.4.0.2
Using uglifier 3.0.1
Using binding_of_caller 0.7.2
Using coffee-script 2.4.1
Using sprockets 3.7.0
Using haml 4.0.7
Using rails_12factor 0.0.3
Using turbolinks 5.0.1
Using sdoc 0.4.1
Using activesupport 4.2.5.2
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    current directory: /usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8/ext/nokogiri
/usr/local/rvm/rubies/ruby-2.3.0/bin/ruby -r ./siteconf20161009-29728-1m9dmos.rb extconf.rb --use-system-libraries
Using pkg-config version 1.1.7
checking if the C compiler accepts -ggdb3 -O0 -std=c11 -Wall -Werror -Wshadow... yes
Building nokogiri using system libraries.
WARNING: libxml2 version 2.9.3 or later is highly recommended, but proceeding anyway.
checking for xmlParseDoc() in libxml/parser.h... yes
checking for xsltParseStylesheetDoc() in libxslt/xslt.h... yes
checking for exsltFuncRegister() in libexslt/exslt.h... yes
checking for xmlHasFeature()... yes
checking for xmlFirstElementChild()... yes
checking for xmlRelaxNGSetParserStructuredErrors()... yes
checking for xmlRelaxNGSetParserStructuredErrors()... yes
checking for xmlRelaxNGSetValidStructuredErrors()... yes
checking for xmlSchemaSetValidStructuredErrors()... yes
checking for xmlSchemaSetParserStructuredErrors()... yes
creating Makefile

To see why this extension failed to compile, please check the mkmf.log which can be found here:

  /usr/local/rvm/gems/ruby-2.3.0/extensions/x86_64-linux/2.3.0/nokogiri-1.6.8/mkmf.log

current directory: /usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8/ext/nokogiri
make "DESTDIR=" clean

current directory: /usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8/ext/nokogiri
make "DESTDIR="
compiling xml_sax_parser.c
error: unknown warning option '-Wno-packed-bitfield-compat'; did you mean '-Wno-keyword-compat'? [-Werror,-Wunknown-warning-option]
make: *** [xml_sax_parser.o] Error 1

make failed, exit code 2

Gem files will remain installed in /usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8 for inspection.
Results logged to /usr/local/rvm/gems/ruby-2.3.0/extensions/x86_64-linux/2.3.0/nokogiri-1.6.8/gem_make.out

An error occurred while installing nokogiri (1.6.8), and Bundler cannot continue.
Make sure that `gem install nokogiri -v '1.6.8'` succeeds before bundling.

~/workspace/CourseSelect/ (master) $ gem install nokogiri -v '1.6.8'

Building native extensions.  This could take a while...
ERROR:  Error installing nokogiri:
        ERROR: Failed to build gem native extension.

    current directory: /usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8/ext/nokogiri
/usr/local/rvm/rubies/ruby-2.3.0/bin/ruby -r ./siteconf20161009-29963-dma39l.rb extconf.rb
Using pkg-config version 1.1.7
checking if the C compiler accepts -ggdb3 -O0 -std=c11 -Wall -Werror -Wshadow... yes
Building nokogiri using packaged libraries.
Using mini_portile version 2.1.0
checking for gzdopen() in -lz... yes
checking for iconv... yes
************************************************************************
IMPORTANT NOTICE:

Building Nokogiri with a packaged version of libxml2-2.9.4.

Team Nokogiri will keep on doing their best to provide security
updates in a timely manner, but if this is a concern for you and want
to use the system library instead; abort this installation process and
reinstall nokogiri as follows:

    gem install nokogiri -- --use-system-libraries
        [--with-xml2-config=/path/to/xml2-config]
        [--with-xslt-config=/path/to/xslt-config]

If you are using Bundler, tell it to use the option:

    bundle config build.nokogiri --use-system-libraries
    bundle install

Note, however, that nokogiri is not fully compatible with arbitrary
versions of libxml2 provided by OS/package vendors.
************************************************************************
Extracting libxml2-2.9.4.tar.gz into tmp/x86_64-pc-linux-gnu/ports/libxml2/2.9.4... OK
Running 'configure' for libxml2 2.9.4... OK
Running 'compile' for libxml2 2.9.4... ERROR, review '/usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8/ext/nokogiri/tmp/x86_64-pc-linux-gnu/ports/libxml2/2.9.4/compile.log' to see what happened. Last lines are:
========================================================================
  CC       entities.lo
  CC       encoding.lo
encoding.c:491:26: error: cast from 'const unsigned char *' to 'unsigned short *' increases required alignment from 1 to 2 [-Werror,-Wcast-align]
    unsigned short* in = (unsigned short*) inb;
                         ^~~~~~~~~~~~~~~~~~~~~
encoding.c:573:27: error: cast from 'unsigned char *' to 'unsigned short *' increases required alignment from 1 to 2 [-Werror,-Wcast-align]
    unsigned short* out = (unsigned short*) outb;
                          ^~~~~~~~~~~~~~~~~~~~~~
encoding.c:729:26: error: cast from 'const unsigned char *' to 'unsigned short *' increases required alignment from 1 to 2 [-Werror,-Wcast-align]
    unsigned short* in = (unsigned short*) inb;
                         ^~~~~~~~~~~~~~~~~~~~~
encoding.c:815:27: error: cast from 'unsigned char *' to 'unsigned short *' increases required alignment from 1 to 2 [-Werror,-Wcast-align]
    unsigned short* out = (unsigned short*) outb;
                          ^~~~~~~~~~~~~~~~~~~~~~
4 errors generated.
make[2]: *** [encoding.lo] Error 1
make[2]: Leaving directory `/usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8/ext/nokogiri/tmp/x86_64-pc-linux-gnu/ports/libxml2/2.9.4/libxml2-2.9.4'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8/ext/nokogiri/tmp/x86_64-pc-linux-gnu/ports/libxml2/2.9.4/libxml2-2.9.4'
make: *** [all] Error 2
========================================================================
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=/usr/local/rvm/rubies/ruby-2.3.0/bin/$(RUBY_BASE_NAME)
        --help
        --clean
        --use-system-libraries
        --enable-static
        --disable-static
        --with-zlib-dir
        --without-zlib-dir
        --with-zlib-include
        --without-zlib-include=${zlib-dir}/include
        --with-zlib-lib
        --without-zlib-lib=${zlib-dir}/lib
        --enable-cross-build
        --disable-cross-build
/usr/local/rvm/gems/ruby-2.3.0/gems/mini_portile2-2.1.0/lib/mini_portile2/mini_portile.rb:366:in `block in execute': Failed to complete compile task (RuntimeError)
        from /usr/local/rvm/gems/ruby-2.3.0/gems/mini_portile2-2.1.0/lib/mini_portile2/mini_portile.rb:337:in `chdir'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/mini_portile2-2.1.0/lib/mini_portile2/mini_portile.rb:337:in `execute'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/mini_portile2-2.1.0/lib/mini_portile2/mini_portile.rb:111:in `compile'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/mini_portile2-2.1.0/lib/mini_portile2/mini_portile.rb:150:in `cook'
        from extconf.rb:364:in `block (2 levels) in process_recipe'
        from extconf.rb:257:in `block in chdir_for_build'
        from extconf.rb:256:in `chdir'
        from extconf.rb:256:in `chdir_for_build'
        from extconf.rb:363:in `block in process_recipe'
        from extconf.rb:262:in `tap'
        from extconf.rb:262:in `process_recipe'
        from extconf.rb:555:in `<main>'

To see why this extension failed to compile, please check the mkmf.log which can be found here:

  /usr/local/rvm/gems/ruby-2.3.0/extensions/x86_64-linux/2.3.0/nokogiri-1.6.8/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /usr/local/rvm/gems/ruby-2.3.0/gems/nokogiri-1.6.8 for inspection.
Results logged to /usr/local/rvm/gems/ruby-2.3.0/extensions/x86_64-linux/2.3.0/nokogiri-1.6.8/gem_make.out

$ rake db:create:all
Specified 'postgresql' for database adapter, but the gem is not loaded. Add gem 'pg' to your Gemfile (and ensure its version is at the minimum required by ActiveRecord).
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_adapters/connection_specification.rb:177:in rescue in spec' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_adapters/connection_specification.rb:174:inspec'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_handling.rb:50:in establish_connection' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:6:inestablish_connection'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:76:in establish_master_connection' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:14:increate'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:93:in create' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:102:inblock in create_all'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:284:in block in each_local_configuration' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:280:ineach_value'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:280:in each_local_configuration' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:102:increate_all'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/railties/databases.rake:11:in block (3 levels) in <top (required)>' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:248:inblock in execute'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:243:in each' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:243:inexecute'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:187:in block in invoke_with_call_chain' /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/monitor.rb:214:inmon_synchronize'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:180:in invoke_with_call_chain' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:173:ininvoke'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:152:in invoke_task' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:inblock (2 levels) in top_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:in each' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:inblock in top_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:117:in run_with_threads' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:102:intop_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:80:in block in run' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:178:instandard_exception_handling'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:77:in run' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/exe/rake:27:in'
/usr/local/rvm/gems/ruby-2.3.0/bin/rake:23:in load' /usr/local/rvm/gems/ruby-2.3.0/bin/rake:23:in

'
Couldn't create database for {"adapter"=>"postgresql", "encoding"=>"unicode", "pool"=>5, "database"=>"courseselect_development"}
Specified 'postgresql' for database adapter, but the gem is not loaded. Add gem 'pg' to your Gemfile (and ensure its version is at the minimum required by ActiveRecord).
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_adapters/connection_specification.rb:177:in rescue in spec' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_adapters/connection_specification.rb:174:inspec'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_handling.rb:50:in establish_connection' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:6:inestablish_connection'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:76:in establish_master_connection' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:14:increate'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:93:in create' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:102:inblock in create_all'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:284:in block in each_local_configuration' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:280:ineach_value'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:280:in each_local_configuration' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:102:increate_all'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/railties/databases.rake:11:in block (3 levels) in <top (required)>' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:248:inblock in execute'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:243:in each' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:243:inexecute'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:187:in block in invoke_with_call_chain' /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/monitor.rb:214:inmon_synchronize'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:180:in invoke_with_call_chain' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:173:ininvoke'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:152:in invoke_task' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:inblock (2 levels) in top_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:in each' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:inblock in top_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:117:in run_with_threads' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:102:intop_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:80:in block in run' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:178:instandard_exception_handling'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:77:in run' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/exe/rake:27:in'
/usr/local/rvm/gems/ruby-2.3.0/bin/rake:23:in load' /usr/local/rvm/gems/ruby-2.3.0/bin/rake:23:in'
Couldn't create database for {"adapter"=>"postgresql", "encoding"=>"unicode", "pool"=>5, "database"=>"courseselect_test"}
Specified 'postgresql' for database adapter, but the gem is not loaded. Add gem 'pg' to your Gemfile (and ensure its version is at the minimum required by ActiveRecord).
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_adapters/connection_specification.rb:177:in rescue in spec' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_adapters/connection_specification.rb:174:inspec'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/connection_handling.rb:50:in establish_connection' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:6:inestablish_connection'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:76:in establish_master_connection' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/postgresql_database_tasks.rb:14:increate'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:93:in create' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:102:inblock in create_all'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:284:in block in each_local_configuration' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:280:ineach_value'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:280:in each_local_configuration' /usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/tasks/database_tasks.rb:102:increate_all'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5/lib/active_record/railties/databases.rake:11:in block (3 levels) in <top (required)>' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:248:inblock in execute'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:243:in each' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:243:inexecute'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:187:in block in invoke_with_call_chain' /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/monitor.rb:214:inmon_synchronize'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:180:in invoke_with_call_chain' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/task.rb:173:ininvoke'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:152:in invoke_task' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:inblock (2 levels) in top_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:in each' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:108:inblock in top_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:117:in run_with_threads' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:102:intop_level'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:80:in block in run' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:178:instandard_exception_handling'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/lib/rake/application.rb:77:in run' /usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/exe/rake:27:in'
/usr/local/rvm/gems/ruby-2.3.0/bin/rake:23:in load' /usr/local/rvm/gems/ruby-2.3.0/bin/rake:23:in'
Couldn't create database for {"adapter"=>"postgresql", "encoding"=>"unicode", "pool"=>5, "database"=>"courseselect_developement"}

`  def openc`
    `@course = Course.find_by_id(params[:id])`
   ` @course.open = true`
      `redirect_to courses_path, flash: {:success => "已经成功开启该课程：#{@course.name}"}`
  `end`

`            <% @course.each do |course| %>`
`......`
`         <% if course.open? %>`
                      ` <td><%= link_to "关闭", close_course_path(course), :method => "get", class: 'btn btn-xs btn-warning' %></td>`
                     `  <% else %>`
                     ` <td><%= link_to "开课", openc_course_path(course), :method => "get", class: 'btn btn-xs btn-success' %></td>`
                    `  <% end %>`
`......`

  def open
    @course=Course.find_by_id(params[:id])
    if @course.open_attributes(course_params)
      flash={:info => "开放成功"}
    else
      flash={:warning => "开放失败"}

  def course_params
    params.require(:course).permit(:course_code, :name, :course_type, :teaching_type, :exam_type,
                                  :credit, :limit_num, :class_room, :course_time, :course_week)
  end

ActionController::ParameterMissing in CoursesController#open
param is missing or the value is empty: course

liaobx:~/workspace (master) $ rake db:seed
rake aborted!
ActiveRecord::RecordInvalid: Validation failed: Email has already been taken
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/validations.rb:79:in `raise_record_invalid'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/validations.rb:43:in `save!'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/attribute_methods/dirty.rb:29:in `save!'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/transactions.rb:291:in `block in save!'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/transactions.rb:351:in `block in with_transaction_returning_status'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/connection_adapters/abstract/database_statements.rb:213:in `block in transaction'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/connection_adapters/abstract/transaction.rb:184:in `within_new_transaction'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/connection_adapters/abstract/database_statements.rb:213:in `transaction'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/transactions.rb:220:in `transaction'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/transactions.rb:348:in `with_transaction_returning_status'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/transactions.rb:291:in `save!'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/persistence.rb:51:in `create!'
/home/ubuntu/workspace/db/seeds.rb:128:in `block in <top (required)>'
/home/ubuntu/workspace/db/seeds.rb:127:in `each'
/home/ubuntu/workspace/db/seeds.rb:127:in `<top (required)>'
/usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5.2/lib/active_support/dependencies.rb:268:in `load'
/usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5.2/lib/active_support/dependencies.rb:268:in `block in load'
/usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5.2/lib/active_support/dependencies.rb:240:in `load_dependency'
/usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5.2/lib/active_support/dependencies.rb:268:in `load'
/usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5.2/lib/rails/engine.rb:547:in `load_seed'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/tasks/database_tasks.rb:250:in `load_seed'
/usr/local/rvm/gems/ruby-2.3.0/gems/activerecord-4.2.5.2/lib/active_record/railties/databases.rake:183:in `block (2 levels) in <top (required)>'
/usr/local/rvm/gems/ruby-2.3.0/gems/rake-11.2.2/exe/rake:27:in `<top (required)>'
/usr/local/rvm/gems/ruby-2.3.0/bin/ruby_executable_hooks:15:in `eval'
/usr/local/rvm/gems/ruby-2.3.0/bin/ruby_executable_hooks:15:in `<main>'
Tasks: TOP => db:seed
(See full trace by running task with --trace)

   我在index.html.erb文件中，不懂link_to后面的语句内容的含义。我有2种代码方案：

 <% if course.open? %>
                       <td><%= link_to "关闭", **close_course_path(course)**, :method => "close", class: 'btn btn-xs btn-info' %></td>
   <% else %>
                      <td><%= link_to "开课", **openc_course_path(course)**, :method => "openc", class: 'btn btn-xs btn-info' %></td>
   <% end %>

 <% if course.open? %>
                       <td><%= link_to "关闭", **courses_path(course)**, :method => "close", class: 'btn btn-xs btn-info' %></td>
   <% else %>
                      <td><%= link_to "开课", **courses_path(course)**, :method => "openc", class: 'btn btn-xs btn-info' %></td>
   <% end %>

Showing /home/ubuntu/workspace/app/views/courses/_form.html.erb where line #8 raised:

undefined method `name' for #<Course id: nil, created_at: nil, updated_at: nil>
Extracted source (around line #8):
              
6    <div class="input-group">
7    <div class="input-group-addon"><span class="glyphicon glyphicon-arrow-right"></span></div>
8    <%= f.text_field :name, class: 'form-control', placeholder: "输入课程名" %>
9    </div>
10   </div>
11   </div>

Trace of template inclusion: app/views/courses/new.html.erb

Rails.root: /home/ubuntu/workspace

<td><%= link_to "编辑", edit_course_url(course), class: 'btn btn-xs btn-info' %></td>

<td><%= link_to "删除", course_path(course), :method => "delete", class: 'btn btn-xs btn-danger', :data => {confirm: '确定要删除此课程?'} %></td>

        <% if student_logged_in? %>
            <li class="list-group-item">
              <%= link_to list_courses_path do %>
                  <span class="glyphicon glyphicon-chevron-right"></span> 开放课程
                  <span class="label label-info pull-right"><%= @num_oppenarray %></span>
              <% end %>

def list
   @course=Course.all
   @course= @course-current_user.courses
   
   @openarray = []
   @course.each do |course| 
           @openarray.push(course) if course.open
   end
   
   @[email protected]
  
 end

 <% if student_logged_in? %>
            <li class="list-group-item">
              <%= link_to list_courses_path do %>
                  <span class="glyphicon glyphicon-chevron-right"></span> 选修课程
                  <span class="label label-info pull-right"><%= (Course.all-current_user.courses).length %></span>
              <% end %>
            </li>
            <li class="list-group-item">
              <%= link_to courses_path do %>
                  <span class="glyphicon glyphicon-chevron-right"></span> 已选课程
                  <span class="label label-info pull-right"><%= current_user.courses.length %></span>
              <% end %>
            </li>
        <% end %>

`Your code is running at https://diycourseselect-balabalahoobala.c9users.io.

=> Booting WEBrick
=> Rails 4.2.5 application starting in development on http://0.0.0.0:8080
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
Exiting
/usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5/lib/active_support/dependencies.rb:268:in `load': /home/ubuntu/workspace/config/routes.rb:4: syntax error, unexpected ':', expecting keyword_end (SyntaxError)
resources: courses
          ^
        from /usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5/lib/active_support/dependencies.rb:268:in `block in load'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5/lib/active_support/dependencies.rb:240:in `load_dependency'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5/lib/active_support/dependencies.rb:268:in `load'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:40:in `block in load_paths'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:40:in `each'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:40:in `load_paths'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:16:in `reload!'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:26:in `block in updater'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5/lib/active_support/file_update_checker.rb:75:in `execute'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:27:in `updater'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:7:in `execute_if_updated'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/finisher.rb:69:in `block in <module:Finisher>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `instance_exec'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `run'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:55:in `block in run_initializers'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:228:in `block in tsort_each'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:350:in `block (2 levels) in each_strongly_connected_component'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:431:in `each_strongly_connected_component_from'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:349:in `block in each_strongly_connected_component'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:347:in `each'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:347:in `call'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:347:in `each_strongly_connected_component'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:226:in `tsort_each'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:205:in `tsort_each'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:54:in `run_initializers'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application.rb:352:in `initialize!'
        from /home/ubuntu/workspace/config/environment.rb:5:in `<top (required)>'
        from /home/ubuntu/workspace/config.ru:3:in `require'
        from /home/ubuntu/workspace/config.ru:3:in `block in <main>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:55:in `instance_eval'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:55:in `initialize'
        from /home/ubuntu/workspace/config.ru:in `new'
        from /home/ubuntu/workspace/config.ru:in `<main>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:49:in `eval'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:49:in `new_from_string'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:40:in `parse_file'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/server.rb:299:in `build_app_and_options_from_config'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/server.rb:208:in `app'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/server.rb:61:in `app'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/server.rb:336:in `wrapped_app'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/server.rb:139:in `log_to_stdout'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/server.rb:78:in `start'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:80:in `block in server'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `tap'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `server'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands.rb:17:in `<top (required)>'
        from /home/ubuntu/workspace/bin/rails:9:in `require'
        from /home/ubuntu/workspace/bin/rails:9:in `<top (required)>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client/rails.rb:28:in `load'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client/rails.rb:28:in `call'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client/command.rb:7:in `call'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client.rb:30:in `run'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/bin/spring:49:in `<top (required)>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/binstub.rb:31:in `load'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/binstub.rb:31:in `<top (required)>'
        from /home/ubuntu/workspace/bin/spring:14:in `require'
        from /home/ubuntu/workspace/bin/spring:14:in `<top (required)>'
        from bin/rails:3:in `load'
        from bin/rails:3:in `<main>'

Rails.application.routes.draw do
  
 
 mount RailsAdmin::Engine => '/admin', as: 'rails_admin'
  root 'homes#index'

  resources :courses do
    member do
      get :select
      get :quit
    end
    collection do
      get :list
    end
  end

  resources :grades, only: [:index, :update]
  resources :users

  get 'sessions/login' => 'sessions#new'
  post 'sessions/login' => 'sessions#create'
  delete 'sessions/logout' => 'sessions#destroy'

end

=> Booting WEBrick
=> Rails 4.2.5 application starting in development on http://0.0.0.0:8080
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
Exiting
/home/ubuntu/workspace/config/routes.rb:4:in `block in <top (required)>': uninitialized constant RailsAdmin (NameError)
        from /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-4.2.5/lib/action_dispatch/routing/route_set.rb:434:in `instance_exec'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-4.2.5/lib/action_dispatch/routing/route_set.rb:434:in `eval_block'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-4.2.5/lib/action_dispatch/routing/route_set.rb:412:in `draw'
        from /home/ubuntu/workspace/config/routes.rb:1:in `<top (required)>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:40:in `block in load_paths'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:40:in `each'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:40:in `load_paths'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:16:in `reload!'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:26:in `block in updater'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/activesupport-4.2.5/lib/active_support/file_update_checker.rb:75:in `execute'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:27:in `updater'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/routes_reloader.rb:7:in `execute_if_updated'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application/finisher.rb:69:in `block in <module:Finisher>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `instance_exec'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `run'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:55:in `block in run_initializers'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:228:in `block in tsort_each'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:350:in `block (2 levels) in each_strongly_connected_component'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:431:in `each_strongly_connected_component_from'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:349:in `block in each_strongly_connected_component'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:347:in `each'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:347:in `call'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:347:in `each_strongly_connected_component'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:226:in `tsort_each'
        from /usr/local/rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/tsort.rb:205:in `tsort_each'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/initializable.rb:54:in `run_initializers'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/application.rb:352:in `initialize!'
        from /home/ubuntu/workspace/config/environment.rb:5:in `<top (required)>'
        from /home/ubuntu/workspace/config.ru:3:in `require'
        from /home/ubuntu/workspace/config.ru:3:in `block in <main>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:55:in `instance_eval'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:55:in `initialize'
        from /home/ubuntu/workspace/config.ru:in `new'
        from /home/ubuntu/workspace/config.ru:in `<main>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:49:in `eval'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:49:in `new_from_string'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/builder.rb:40:in `parse_file'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/server.rb:299:in `build_app_and_options_from_config'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/server.rb:208:in `app'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/server.rb:61:in `app'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/rack-1.6.4/lib/rack/server.rb:336:in `wrapped_app'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/server.rb:139:in `log_to_stdout'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/server.rb:78:in `start'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:80:in `block in server'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `tap'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `server'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/railties-4.2.5/lib/rails/commands.rb:17:in `<top (required)>'
        from /home/ubuntu/workspace/bin/rails:9:in `require'
        from /home/ubuntu/workspace/bin/rails:9:in `<top (required)>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client/rails.rb:28:in `load'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client/rails.rb:28:in `call'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client/command.rb:7:in `call'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/client.rb:30:in `run'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/bin/spring:49:in `<top (required)>'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/binstub.rb:31:in `load'
        from /usr/local/rvm/gems/ruby-2.3.0/gems/spring-2.0.0/lib/spring/binstub.rb:31:in `<top (required)>'
        from /home/ubuntu/workspace/bin/spring:14:in `require'
        from /home/ubuntu/workspace/bin/spring:14:in `<top (required)>'
        from bin/rails:3:in `load'
        from bin/rails:3:in `<main>'
`

class AddOpenAttribute < ActiveRecord::Migration
  def change
        add_column :courses, :open, :boolean, :default => false
  end
end

def list
    @course=Course.all
    @course=@course-current_user.courses
    @course.each do |t|                                       //通过循环把所有open的课程赋值给了putcourse数组后，如
      if (@course.open==true) then                     //把这个数组传给视图
        putcourse[t]=@course
      end
    end
  end

 def open
    @course=Course.find_by_id(params[:id])
    @course.opencourse=1
    redirect_to courses_path, flash: {:success => "已经成功开启该课程:#{ @course.opencourse}"}
  end

  def open
    @course=Course.find_by_id(params[:id])
    @course.opencourse=1
    redirect_to courses_path, flash: {:success => "已经成功开启该课程:#{ @course.opencourse}"}
  end

       <div class="panel-body">
          <table class="table table-responsive table-condensed table-hover">
            <thead>
            <tr>
              <th>课程编号</th>
              <th>课程名称</th>
              <th>课时/学分</th>
              <th>考试方式</th>
              <th>主讲教师</th>
              _**# <th>是否开课</th>**_
            </tr>

            <tbody>
            <% @course.each do |course| %>
                <tr>

                  <td><%= course.course_code %></td>
                  <td><%= course.name %></td>
                  <td><%= course.credit %></td>
                  <td><%= course.exam_type %></td>
                  <td><%= course.teacher.name %></td>
                  # **_<td><%= course.opencourse %></td>_**

                  <% if teacher_logged_in? %>
                      <td><%= link_to "编辑", edit_course_url(course), class: 'btn btn-xs btn-info' %></td>
                      **# _<td><%= link_to "开课", open_course_url(course), class: 'btn btn-xs btn-info' %></td>_**
                      <td><%= link_to "删除", course_path(course), :method => "delete", class: 'btn btn-xs btn-danger', :data => {confirm: '确定要删除此课程?'} %></td>
                  <% elsif student_logged_in? %>

def open
    @course=Course.find_by_id(params[:id])
    @course.open_close=true
    @course.save
    redirect_to courses_path, flash: {:success => "已经成功开启该课程:#{ @course.name}"}
  end

def course_params
    params.require(:course).permit(:course_code, :name, :course_type, :teaching_type, :exam_type,
                                   :credit, :limit_num, :class_room, :course_time, :course_week, :open_close)
  end