尝试在heroku上访问我的应用时出现以下错误。该应用程序已成功部署，但我无法访问它。当我尝试访问该应用程序时，该页面显示“应用程序错误 应用程序中发生错误，无法提供您的页面。如果您是应用程序所有者，请检查日志以获取详细信息。“这是heroku日志：
heroku logs
2017-03-21T20:28:21.577989+00:00 app[web.1]: from /app/config.ru:in `<main>'
2017-03-21T20:28:21.578004+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:49:in `eval'
2017-03-21T20:28:21.578005+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:49:in `new_from_string'
2017-03-21T20:28:21.578007+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:40:in `parse_file'
2017-03-21T20:28:21.578008+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:318:in `build_app_and_options_from_config'
2017-03-21T20:28:21.578010+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:218:in `app'
2017-03-21T20:28:21.749663+00:00 heroku[web.1]: Process exited with status 1
2017-03-21T20:28:21.578012+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/server.rb:59:in `app'
2017-03-21T20:28:21.578026+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:353:in `wrapped_app'
2017-03-21T20:28:21.578029+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:282:in `start'
2017-03-21T20:28:21.578030+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/server.rb:79:in `start'
2017-03-21T20:28:21.578032+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:90:in `block in serv er'
2017-03-21T20:28:21.578033+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:85:in `tap'
2017-03-21T20:28:21.578035+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:85:in `server'
2017-03-21T20:28:21.578037+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
2017-03-21T20:28:21.578052+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands.rb:18:in `<top (required)>'
2017-03-21T20:28:21.578078+00:00 app[web.1]: from bin/rails:4:in `require'
2017-03-21T20:28:21.578079+00:00 app[web.1]: from bin/rails:4:in `<main>'
2017-03-21T20:28:21.768673+00:00 heroku[web.1]: State changed from starting to c rashed
2017-03-21T20:28:23.139347+00:00 heroku[router]: at=error code=H10 desc="App cra shed" method=GET path="/recipes" host=weather-consult.herokuapp.com request_id=9 801a23f-72b9-4477-8e90-93fba979e78f fwd="83.138.193.223" dyno= connect= service= status=503 bytes= protocol=https
2017-03-21T20:28:23.718785+00:00 heroku[router]: at=error code=H10 desc="App cra shed" method=GET path="/favicon.ico" host=weather-consult.herokuapp.com request_ id=100c960d-b3a1-4374-ae56-52e60b785710 fwd="83.138.193.223" dyno= connect= serv ice= status=503 bytes= protocol=https
2017-03-21T20:28:40.702732+00:00 heroku[web.1]: State changed from crashed to st arting
2017-03-21T20:28:43.480189+00:00 heroku[web.1]: Starting process with command `b in/rails server -p 41364 -e production`
2017-03-21T20:28:48.023383+00:00 app[web.1]: => Rails 5.0.2 application starting in production on http://0.0.0.0:41364
2017-03-21T20:28:48.023384+00:00 app[web.1]: => Run `rails server -h` for more s tartup options
2017-03-21T20:28:48.023369+00:00 app[web.1]: => Booting Puma
2017-03-21T20:28:48.023384+00:00 app[web.1]: Exiting
2017-03-21T20:28:48.023457+00:00 app[web.1]: /app/vendor/bundle/ruby/2.2.0/gems/ activerecord-5.0.2/lib/active_record/connection_adapters/connection_specificatio n.rb:176:in `rescue in spec': Specified 'postgresql' for database adapter, but t he gem is not loaded. Add `gem 'pg'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord). (Gem::LoadError)
2017-03-21T20:28:48.023485+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activerecord-5.0.2/lib/active_record/connection_adapters/connection_spec ification.rb:173:in `spec'
2017-03-21T20:28:48.023486+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activerecord-5.0.2/lib/active_record/connection_handling.rb:53:in `estab lish_connection'
2017-03-21T20:28:48.023487+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activerecord-5.0.2/lib/active_record/railtie.rb:125:in `block (2 levels) in <class:Railtie>'
2017-03-21T20:28:48.023531+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/lazy_load_hooks.rb:49:in `each'
2017-03-21T20:28:48.023532+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/lazy_load_hooks.rb:49:in `run_loa d_hooks'
2017-03-21T20:28:48.023526+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/lazy_load_hooks.rb:43:in `instanc e_eval'
2017-03-21T20:28:48.023527+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/lazy_load_hooks.rb:43:in `execute _hook'
2017-03-21T20:28:48.023534+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activerecord-5.0.2/lib/active_record/base.rb:324:in `<module:ActiveRecor d>'
2017-03-21T20:28:48.023528+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/lazy_load_hooks.rb:50:in `block i n run_load_hooks'
2017-03-21T20:28:48.023535+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activerecord-5.0.2/lib/active_record/base.rb:24:in `<top (required)>'
2017-03-21T20:28:48.023537+00:00 app[web.1]: from /app/app/models/application _record.rb:1:in `<top (required)>'
2017-03-21T20:28:48.023539+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:293:in `require'
2017-03-21T20:28:48.023569+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:37:in `block in l oad_interlock'
2017-03-21T20:28:48.023564+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:293:in `block in require'
2017-03-21T20:28:48.023590+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies/interlock.rb:12:in ` block in loading'
2017-03-21T20:28:48.023565+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:259:in `load_depe ndency'
2017-03-21T20:28:48.023590+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/concurrency/share_lock.rb:150:in `exclusive'
2017-03-21T20:28:48.023566+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:293:in `require'
2017-03-21T20:28:48.023568+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:380:in `block in require_or_load'
2017-03-21T20:28:48.023591+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies/interlock.rb:11:in ` loading'
2017-03-21T20:28:48.023592+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:37:in `load_inter lock'
2017-03-21T20:28:48.023593+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:358:in `require_o r_load'
2017-03-21T20:28:48.023599+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/engine.rb:473:in `each'
2017-03-21T20:28:48.023598+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/engine.rb:475:in `block in eager_load!'
2017-03-21T20:28:48.023600+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/engine.rb:473:in `eager_load!'
2017-03-21T20:28:48.023594+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:336:in `depend_on '
2017-03-21T20:28:48.023594+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/activesupport-5.0.2/lib/active_support/dependencies.rb:252:in `require_d ependency'
2017-03-21T20:28:48.023597+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/engine.rb:475:in `each'
2017-03-21T20:28:48.023595+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/engine.rb:476:in `block (2 levels) in eager_loa d!'
2017-03-21T20:28:48.023602+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/engine.rb:354:in `eager_load!'
2017-03-21T20:28:48.023603+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/application/finisher.rb:59:in `each'
2017-03-21T20:28:48.023605+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/application/finisher.rb:59:in `block in <module :Finisher>'
2017-03-21T20:28:48.023606+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/initializable.rb:30:in `instance_exec'
2017-03-21T20:28:48.023626+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:348:in `block (2 levels) in each_strongly_connected_componen t'
2017-03-21T20:28:48.023608+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/initializable.rb:30:in `run'
2017-03-21T20:28:48.023628+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:429:in `each_strongly_connected_component_from'
2017-03-21T20:28:48.023639+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:347:in `block in each_strongly_connected_component'
2017-03-21T20:28:48.023610+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/initializable.rb:55:in `block in run_initialize rs'
2017-03-21T20:28:48.023612+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:226:in `block in tsort_each'
2017-03-21T20:28:48.023641+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:345:in `each'
2017-03-21T20:28:48.023643+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:345:in `call'
2017-03-21T20:28:48.023649+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:345:in `each_strongly_connected_component'
2017-03-21T20:28:48.023663+00:00 app[web.1]: from /app/config/environment.rb: 5:in `<top (required)>'
2017-03-21T20:28:48.023651+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:224:in `tsort_each'
2017-03-21T20:28:48.023653+00:00 app[web.1]: from /app/vendor/ruby-2.2.6/lib/ ruby/2.2.0/tsort.rb:203:in `tsort_each'
2017-03-21T20:28:48.023665+00:00 app[web.1]: from /app/config.ru:3:in `requir e_relative'
2017-03-21T20:28:48.023655+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/initializable.rb:54:in `run_initializers'
2017-03-21T20:28:48.023671+00:00 app[web.1]: from /app/config.ru:3:in `block in <main>'
2017-03-21T20:28:48.023661+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/application.rb:352:in `initialize!'
2017-03-21T20:28:48.023673+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:55:in `instance_eval'
2017-03-21T20:28:48.023675+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:55:in `initialize'
2017-03-21T20:28:48.023678+00:00 app[web.1]: from /app/config.ru:in `new'
2017-03-21T20:28:48.023683+00:00 app[web.1]: from /app/config.ru:in `<main>'
2017-03-21T20:28:48.023696+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:318:in `build_app_and_options_from_config'
2017-03-21T20:28:48.023697+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:218:in `app'
2017-03-21T20:28:48.023685+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:49:in `eval'
2017-03-21T20:28:48.023700+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/server.rb:59:in `app'
2017-03-21T20:28:48.023687+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:49:in `new_from_string'
2017-03-21T20:28:48.023690+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/builder.rb:40:in `parse_file'
2017-03-21T20:28:48.023702+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:353:in `wrapped_app'
2017-03-21T20:28:48.023704+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/rack-2.0.1/lib/rack/server.rb:282:in `start'
2017-03-21T20:28:48.023710+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/server.rb:79:in `start'
2017-03-21T20:28:48.023712+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:90:in `block in serv er'
2017-03-21T20:28:48.023714+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:85:in `tap'
2017-03-21T20:28:48.023715+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:85:in `server'
2017-03-21T20:28:48.023724+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands.rb:18:in `<top (required)>'
2017-03-21T20:28:48.023718+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2 .0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
2017-03-21T20:28:48.023726+00:00 app[web.1]: from bin/rails:4:in `require'
2017-03-21T20:28:48.023732+00:00 app[web.1]: from bin/rails:4:in `<main>'
2017-03-21T20:28:48.114357+00:00 heroku[web.1]: Process exited with status 1
2017-03-21T20:28:48.128920+00:00 heroku[web.1]: State changed from starting to c rashed
2017-03-21T20:28:49.680428+00:00 heroku[router]: at=error code=H10 desc="App cra shed" method=GET path="/recipes" host=weather-consult.herokuapp.com request_id=a 42f1683-8c92-412e-bc36-35bee47fd044 fwd="83.138.193.223" dyno= connect= service= status=503 bytes= protocol=https
2017-03-21T20:28:50.139167+00:00 heroku[router]: at=error code=H10 desc="App cra shed" method=GET path="/favicon.ico" host=weather-consult.herokuapp.com request_ id=70b71bcf-af11-489f-bdee-f3325249f7fe fwd="83.138.193.223" dyno= connect= serv ice= status=503 bytes= protocol=https
答案 0 :(得分：1)
你的Gemfile中一定不能有pg，这让我觉得你可能缺少gemfile中特定于部署的东西。找到sqlite3或等效的开发数据库gem并在gemfile中重新构建它，这通常是它的完成方式。 Heroku自动寻找：生产环境并加载适用的配置。
group :development do
# Access an IRB console on exception pages or by using <%= console %> anywhere in the code.
gem 'web-console', '>= 3.3.0'
gem 'sqlite3'
end
group :production do
gem 'pg'
gem 'rails_12factor'
gem 'letsencrypt-rails-heroku'
end
当您的架构发生更改时忘记迁移数据库时，有时也会遇到该错误。您可以使用heroku run rake db:migrate。
答案 1 :(得分：0)
尝试重新启动dynos。
heroku ps:restart
或只是尝试heroku restart
答案 2 :(得分：0)
您需要更新问题中的日志，以便它们更具可读性。在使用Postgresql时，需要将pg添加到Gemfile中。
The gem is not loaded. Add `gem 'pg'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord).(Gem::LoadError)