所以我正在玩mongo的东西。创建了一个新的heroku应用程序，为它添加了一个mongolab选项，但是每个mongoid方法都失败了。
我用Google搜索了，看起来这个问题在1.9.3之前的红宝石中很常见，但我运行的是1.9.3。
这是最简单的失败样本：
require 'sinatra'
require 'mongoid'
require 'json'
require "sinatra/reloader" if development?
Mongoid.load!("mongoid.yml")
class Company
include Mongoid::Document
field :code, type: String
field :sector, type: String
field :share_id, type: Integer
field :jse_code, type: Integer
end
get '/' do
"Hello"
end
get '/company' do
Company.exists?
end
我在本地（对mongolab db）或heroku运行，我得到同样的错误：
12:22:33 web.1 | NoMethodError - undefined method `match' for nil:NilClass:
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions/mongo_uri.rb:49:in `initialize'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions/factory.rb:103:in `new'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions/factory.rb:103:in `parse'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions/factory.rb:62:in `create_session'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions/factory.rb:43:in `default'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions.rb:109:in `default'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions.rb:378:in `__session__'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions.rb:213:in `mongo_session'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/sessions.rb:157:in `collection'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/contextual/mongo.rb:216:in `initialize'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/contextual.rb:47:in `new'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/contextual.rb:47:in `create_context'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/contextual.rb:30:in `context'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/contextual.rb:20:in `rescue in exists?'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/contextual.rb:18:in `exists?'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/mongoid-3.0.13/lib/mongoid/finders.rb:43:in `exists?'
12:22:33 web.1 | app.rb:22:in `block in <main>'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:1265:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:1265:in `block in compile!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:835:in `[]'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:835:in `block (3 levels) in route!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:851:in `route_eval'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:835:in `block (2 levels) in route!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:872:in `block in process_route'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:870:in `catch'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:870:in `process_route'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:834:in `block in route!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:833:in `each'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:833:in `route!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:936:in `dispatch!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:769:in `block in call!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:921:in `block in invoke'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:921:in `catch'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:921:in `invoke'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:769:in `call!'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:755:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-protection-1.2.0/lib/rack/protection/xss_header.rb:22:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-protection-1.2.0/lib/rack/protection/path_traversal.rb:16:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-protection-1.2.0/lib/rack/protection/json_csrf.rb:17:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-protection-1.2.0/lib/rack/protection/base.rb:47:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-protection-1.2.0/lib/rack/protection/xss_header.rb:22:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-1.4.1/lib/rack/logger.rb:15:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-1.4.1/lib/rack/commonlogger.rb:20:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:136:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:129:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-1.4.1/lib/rack/head.rb:9:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/rack-1.4.1/lib/rack/methodoverride.rb:21:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/showexceptions.rb:21:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:99:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:1389:in `block in call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:1471:in `synchronize'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/sinatra-1.3.3/lib/sinatra/base.rb:1389:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/thin-1.5.0/lib/thin/connection.rb:81:in `block in pre_process'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/thin-1.5.0/lib/thin/connection.rb:79:in `catch'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/thin-1.5.0/lib/thin/connection.rb:79:in `pre_process'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/eventmachine-1.0.0/lib/eventmachine.rb:1037:in `call'
12:22:33 web.1 | /Users/sdx/.rvm/gems/ruby-1.9.3-p327/gems/eventmachine-1.0.0/lib/eventmachine.rb:1037:in `block in spawn_threadpool'
12:22:33 web.1 | 127.0.0.1 - - [21/Nov/2012 12:22:33] "GET /__sinatra__/500.png HTTP/1.1" 200 31056 0.0062
我做错了什么？
更新这是我的mongoid.yml：
production:
sessions:
default:
uri: <%= ENV['MONGOLAB_URI'] %>
options:
skip_version_check: true
safe: true
development:
sessions:
default:
uri: <%= ENV['MONGOLAB_URI'] %>
答案 0 :(得分：9)
基于堆栈跟踪，看起来mongo_uri的构造函数正在传递空值。我会在mongoid.yml中检查以下内容：
load!的参数指向正确的位置MONGOLAB_URI），那么它们将在您的环境中设置来自mongo_uri.rb:49的相关行，其中抛出异常：
# Create the new uri from the provided string.
#
# @example Create the new uri.
# MongoUri.new(uri)
#
# @param [ String ] string The uri string.
#
# @since 3.0.0
def initialize(string)
@match = string.match(URI)
end
答案 1 :(得分：6)
在编译资产时，它与heroku有关，而不是使用环境变量。
使用heroku的此实验室功能将有助于解决此问题：https://devcenter.heroku.com/articles/labs-user-env-compile