如何在开发中调试卡住的 Rails 进程？

Question

我正在将我的旧 Rails 4.2 应用程序升级到 Rails 5。我目前正在尝试使其在 5.1 上工作。 当我尝试访问正在开发的应用程序的页面时，它似乎可以正常启动并开始呈现。 浏览器永远不会收到来自服务器的响应，服务器只是停止输出到日志。 我无法弄清楚发生了什么。

我怎样才能进一步调试它为什么挂起并且从不响应？

Output rails s :

=> Booting Puma
=> Rails 5.1.7 application starting in development 
=> Run `rails server -h` for more startup options
Puma starting in single mode...
* Version 4.3.3 (ruby 2.6.5-p114), codename: Mysterious Traveller
* Min threads: 1, max threads: 1
* Environment: development
* Listening on tcp://127.0.0.1:3000
* Listening on tcp://[::1]:3000
Use Ctrl-C to stop
I, [2020-04-27T15:18:05.059708 #75800]  INFO -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b] Started GET "/" for 127.0.0.1 at 2020-04-27 15:18:05 +0200
D, [2020-04-27T15:18:05.608709 #75800] DEBUG -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b]    (3.6ms)  SELECT "schema_migrations"."version" FROM "schema_migrations" ORDER BY "schema_migrations"."version" ASC /*application:MyApp*/
I, [2020-04-27T15:18:06.590249 #75800]  INFO -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b] Processing by MyAppController#front_page as HTML
D, [2020-04-27T15:18:06.613950 #75800] DEBUG -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b]   User Load (0.7ms)  SELECT  "da"."users".* FROM "da"."users" WHERE "da"."users"."auth_token" = $1 LIMIT $2 /*application:MyApp,line:/app/controllers/controller_concerns/session_handling.rb:35:in `current_user'*/  [["auth_token", "uWOt-zCVDbo8a6AT-SkWUQ"], ["LIMIT", 1]]
I, [2020-04-27T15:18:06.766078 #75800]  INFO -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b]   Rendering myapp/front_page.html.haml within layouts/front_page
D, [2020-04-27T15:18:06.866720 #75800] DEBUG -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b]   Car Load (3.1ms)  SELECT  "cars".* FROM "cars" WHERE "cars"."user_id" = $1 AND "cars"."sales_state" = $2 ORDER BY "cars"."id" DESC LIMIT $3 /*application:MyApp,controller:myapp,action:front_page,controller_with_namespace:MyAppController,line:/app/controllers/controller_concerns/user_listings.rb:11:in `last_on_hold_listing'*/  [["user_id", 900000000], ["sales_state", "on_hold"], ["LIMIT", 1]]
D, [2020-04-27T15:18:06.929863 #75800] DEBUG -- : [Redis] command=GET args="da/brands_and_model_names/v1.0"
D, [2020-04-27T15:18:06.932895 #75800] DEBUG -- : [Redis] call_time=2.90 ms
I, [2020-04-27T15:18:07.071685 #75800]  INFO -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b]   Rendered partials/_extended_search_form.html.haml (193.3ms)
I, [2020-04-27T15:18:07.242322 #75800]  INFO -- : [83adaf81-4bf7-4870-b5f8-b6c0c11a4d2b]   Rendered partials/_front_page_featured_items.html.haml (160.4ms)

它只是停在看起来要在 rails 中完成处理的地方，并且应该将响应发送到浏览器。 相反，它就像我在代码中有一个binding.pry一样挂起 - 但我没有。 日志中没有发出任何内容。 我什至无法停止服务器，我必须手动将其杀死。 ruby 进程的 CPU 在 0% 时处于空闲状态。

顺便说一句， rails console工作正常。

我还能做些什么来弄清楚它卡在哪里？

UDPATE

我怀疑它可能与资产编译有关。 在我的旧 rails 4.2 分支中，到达日志中的特定点后，它将开始在开发中即时编译资产，但是在 rails 5.2 分支中不会发生这种情况。 现在运行时： bin/rails assets:precompile我得到：

yarn install v1.22.4
warning package.json: No license field
warning package-lock.json found. Your project contains lock files generated by tools other than Yarn. It is advised not to mix package managers in order to avoid resolution inconsistencies caused by unsynchronized lock files. To clear this warning, remove package-lock.json.
warning No license field
[1/4] 🔍  Resolving packages...
success Already up-to-date.
✨  Done in 0.72s.
yarn install v1.22.4
warning package.json: No license field
warning package-lock.json found. Your project contains lock files generated by tools other than Yarn. It is advised not to mix package managers in order to avoid resolution inconsistencies caused by unsynchronized lock files. To clear this warning, remove package-lock.json.
warning No license field
[1/4] 🔍  Resolving packages...
success Already up-to-date.
✨  Done in 0.60s.
rails aborted!
ExecJS::RuntimeError: SyntaxError: [stdin]:1:1: unexpected //=
compile ((execjs):7528:19)
eval (eval at <anonymous> ((execjs):7539:8), <anonymous>:1:10)
(execjs):7539:8
(execjs):7545:14
(execjs):1:40
Object.<anonymous> ((execjs):1:58)
Module._compile (internal/modules/cjs/loader.js:1156:30)
Object.Module._extensions..js (internal/modules/cjs/loader.js:1176:10)
Module.load (internal/modules/cjs/loader.js:1000:32)
Function.Module._load (internal/modules/cjs/loader.js:899:14)
Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)
internal/main/run_main_module.js:18:47
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/execjs-2.7.0/lib/execjs/external_runtime.rb:39:in `exec'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/execjs-2.7.0/lib/execjs/external_runtime.rb:21:in `eval'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/execjs-2.7.0/lib/execjs/external_runtime.rb:46:in `call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/coffee-script-2.4.1/lib/coffee_script.rb:78:in `compile'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/coffee_script_processor.rb:24:in `block in call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/cache.rb:92:in `fetch'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/coffee_script_processor.rb:23:in `call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:84:in `call_processor'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:66:in `block in call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `reverse_each'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:22:in `block in <class:CompositeProcessor>'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:33:in `call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:84:in `call_processor'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:66:in `block in call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `reverse_each'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:182:in `load_from_unloaded'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:59:in `block in load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:335:in `fetch_asset_from_dependency_cache'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:43:in `load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/cached_environment.rb:44:in `load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/bundle.rb:41:in `block in call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/utils.rb:167:in `dfs'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/bundle.rb:42:in `call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:84:in `call_processor'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:66:in `block in call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `reverse_each'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:182:in `load_from_unloaded'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:59:in `block in load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:335:in `fetch_asset_from_dependency_cache'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:43:in `load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/cached_environment.rb:44:in `load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/bundle.rb:32:in `block in call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/bundle.rb:31:in `call'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:84:in `call_processor'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:66:in `block in call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `reverse_each'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/processor_utils.rb:65:in `call_processors'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:182:in `load_from_unloaded'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:59:in `block in load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:335:in `fetch_asset_from_dependency_cache'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/loader.rb:43:in `load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/cached_environment.rb:44:in `load'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/base.rb:81:in `find_asset'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/base.rb:88:in `find_all_linked_assets'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/sprockets-4.0.0/lib/sprockets/manifest.rb:125:in `block (2 levels) in find'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/safe_task_executor.rb:24:in `block in execute'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/synchronization/mutex_lockable_object.rb:41:in `block in synchronize'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/synchronization/mutex_lockable_object.rb:41:in `synchronize'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/synchronization/mutex_lockable_object.rb:41:in `synchronize'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/safe_task_executor.rb:19:in `execute'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/promise.rb:563:in `block in realize'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/ruby_thread_pool_executor.rb:353:in `run_task'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/ruby_thread_pool_executor.rb:342:in `block (3 levels) in create_worker'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/ruby_thread_pool_executor.rb:325:in `loop'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/ruby_thread_pool_executor.rb:325:in `block (2 levels) in create_worker'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/ruby_thread_pool_executor.rb:324:in `catch'
/Users/nielsk/.rvm/gems/ruby-2.6.5@rails52/gems/concurrent-ruby-1.1.6/lib/concurrent-ruby/concurrent/executor/ruby_thread_pool_executor.rb:324:in `block in create_worker'
Tasks: TOP => assets:precompile
(See full trace by running task with --trace)

这可能是什么？

Answer 1

检查您是否使用//=语法来要求 CoffeeScript 文件中的文件。 显然，在 sprockets 4 中不再支持。

您应该将所有//= in.coffee 文件替换为#=

免责声明：我正在从事与 OP 相同的项目:)