从Rails 3升级后在Rails 4中可安装的引擎路由错误

Question

我在我们的Rails 4.2.4应用程序中使用某些可安装的引擎时遇到了一些问题。我们最近（我知道，我们很晚很难过）从Rails 3.2.23升级。我们的引擎路由在Rails 3.2.23中运行良好，但是当我尝试访问路由时（使用Paw或cURL），我得到一个RoutingError，没有路由匹配。但是，当我查看rake routes或http://localhost:3000/rails/info/routes的输出时，该路线实际上存在与正确的动词和所有内容。

事情我看着：

• 路线不被别的东西下来的文件覆盖，因为我们所拥有的一切包在子域的限制。
• 我重新创建了可安装引擎，使用最新版本的Rails并比较了差异。

此外，我正在使用versionist宝石。我不知道这是否是造成这种情况的原因，但似乎相关。

的Gemfile

gem 'api', path: 'engines/api' 

配置/ routes.rb中

constraints subdomain: /^api/, format: :json do 
    mount Api::Engine, at: "/" 
end 

引擎/ API/LIB/API/engine.rb

module Api 
    class Engine < ::Rails::Engine 
    isolate_namespace Api 

    config.generators do |g| 
     g.template_engine :rabl 
     g.test_framework :rspec, view_specs: false 
    end 
    end 
end 

引擎/ API /配置/ routes.rb中

Api::Engine.routes.draw do 
    api_version(:module => "V1", :parameter => { :name => "version", :value => "1" }) do 
    resources :users 
    end 
end 

样品卷曲请求

curl -X "GET" "http://api.myapp.dev:3000/users/new?api_key=foobar&version=1" \ 
-H "Accept: application/json" \ 
-H "Content-Type: application/json" 

日志/ development.log

ActionController::RoutingError (No route matches [GET] "https://stackoverflow.com/users/new"): 
    actionpack (4.2.4) lib/action_dispatch/middleware/debug_exceptions.rb:21:in `call' 
    rollbar (2.3.0) lib/rollbar/middleware/rails/show_exceptions.rb:22:in `call_with_rollbar' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    web-console (2.2.1) lib/web_console/middleware.rb:39:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    actionpack (4.2.4) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    railties (4.2.4) lib/rails/rack/logger.rb:38:in `call_app' 
    railties (4.2.4) lib/rails/rack/logger.rb:20:in `block in call' 
    activesupport (4.2.4) lib/active_support/tagged_logging.rb:68:in `block in tagged' 
    activesupport (4.2.4) lib/active_support/tagged_logging.rb:26:in `tagged' 
    activesupport (4.2.4) lib/active_support/tagged_logging.rb:68:in `tagged' 
    railties (4.2.4) lib/rails/rack/logger.rb:20:in `call' 
    quiet_assets (1.1.0) lib/quiet_assets.rb:27:in `call_with_quiet_assets' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    request_store (1.2.0) lib/request_store/middleware.rb:8:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    actionpack (4.2.4) lib/action_dispatch/middleware/request_id.rb:21:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    rack (1.6.4) lib/rack/methodoverride.rb:22:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    rack (1.6.4) lib/rack/runtime.rb:18:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    activesupport (4.2.4) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    rack (1.6.4) lib/rack/lock.rb:17:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    rack (1.6.4) lib/rack/sendfile.rb:113:in `call' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    railties (4.2.4) lib/rails/engine.rb:518:in `call' 
    railties (4.2.4) lib/rails/application.rb:165:in `call' 
    railties (4.2.4) lib/rails/railtie.rb:194:in `public_send' 
    railties (4.2.4) lib/rails/railtie.rb:194:in `method_missing' 
    newrelic_rpm (3.13.2.302) lib/new_relic/agent/instrumentation/middleware_tracing.rb:67:in `call' 
    passenger (5.0.20) src/ruby_supportlib/phusion_passenger/rack/thread_handler_extension.rb:94:in `process_request' 
    passenger (5.0.20) src/ruby_supportlib/phusion_passenger/request_handler/thread_handler.rb:151:in `accept_and_process_next_request' 
    passenger (5.0.20) src/ruby_supportlib/phusion_passenger/request_handler/thread_handler.rb:112:in `main_loop' 
    passenger (5.0.20) src/ruby_supportlib/phusion_passenger/request_handler.rb:415:in `block (3 levels) in start_threads' 
    passenger (5.0.20) src/ruby_supportlib/phusion_passenger/utils.rb:112:in `block in create_thread_and_abort_on_exception' 

Answer 1

所以我想出答案，它在约束条件中所接受的句法中发生了如此微妙的变化。我最终删除了mount调用之上的格式约束，并将其移至引擎路由中。现在，该代码如下所示：

的config/routes.rb中

mount Api::Engine, at: '/', constraints: { subdomain: /^api/ } 

引擎/ API /配置/ routes.rb中

Api::Engine.routes.draw do 
    api_version(module: "V1", parameter: { name: "version", value: "1" }) do 
    constraints format: :json do # Added the format constraint here. 
     resources :users 
    end 
    end 
end 

希望这可以帮助别人，因为它花了我花了一段时间来确定问题。