Question

My Mad Libs程序（code，Heroku app; earlier version on repl.it）在我的Ubuntu VirtualBox中正常运行，在将代码推送到Heroku后几分钟，它实际上正在运行Heroku也是。然后在大概15到30分钟之后，我在服务器上做了一些事情或事情，并且自从应用页面说出＆＃34;内部服务器错误＆＃34;以及服务器日志的相关部分：

2018-04-14T02:03:45.717579+00:00 heroku[web.1]: Starting process with command `bundle exec ruby app.rb -p 7330`
2018-04-14T02:03:48.443468+00:00 app[web.1]: [2018-04-14 02:03:48] INFO  ruby 2.4.0 (2016-12-24) [x86_64-linux]
2018-04-14T02:03:48.443866+00:00 app[web.1]: == Sinatra (v2.0.1) has taken the stage on 7330 for production with backup from WEBrick
2018-04-14T02:03:48.443437+00:00 app[web.1]: [2018-04-14 02:03:48] INFO  WEBrick 1.3.1
2018-04-14T02:03:48.444166+00:00 app[web.1]: [2018-04-14 02:03:48] INFO  WEBrick::HTTPServer#start: pid=4 port=7330
2018-04-14T02:03:48.855874+00:00 heroku[web.1]: State changed from starting to up
2018-04-14T02:04:04.372745+00:00 heroku[router]: at=info method=GET path="/" host=youmadlibs.herokuapp.com request_id=118d681f-3402-44aa-9d04-75d930461195 fwd="74.135.49.116" dyno=web.1 connect=0ms service=20ms status=500 bytes=854 protocol=https
2018-04-14T02:04:04.368607+00:00 app[web.1]: 2018-04-14 02:04:04 - PG::ConnectionBad - could not connect to server: Connection refused
2018-04-14T02:04:04.368644+00:00 app[web.1]:    Is the server running on host "localhost" (127.0.0.1) and accepting
2018-04-14T02:04:04.368648+00:00 app[web.1]:    TCP/IP connections on port 5432?
2018-04-14T02:04:04.368651+00:00 app[web.1]: :
2018-04-14T02:04:04.368653+00:00 app[web.1]:    /app/vendor/bundle/ruby/2.4.0/gems/pg-1.0.0/lib/pg.rb:56:in `initialize'
2018-04-14T02:04:04.368654+00:00 app[web.1]:    /app/vendor/bundle/ruby/2.4.0/gems/pg-1.0.0/lib/pg.rb:56:in `new'
2018-04-14T02:04:04.368656+00:00 app[web.1]:    /app/vendor/bundle/ruby/2.4.0/gems/pg-1.0.0/lib/pg.rb:56:in `connect'
2018-04-14T02:04:04.368659+00:00 app[web.1]:    /app/vendor/bundle/ruby/2.4.0/gems/activerecord-5.2.0/lib/active_record/connection_adapters/postgresql_adapter.rb:684:in `connect'
etc.

相关的行似乎是：

PG::ConnectionBad - could not connect to server: Connection refused
Is the server running on host "localhost" (127.0.0.1) and accepting TCP/IP connections on port 5432?

我尝试了很多东西，比如重新启动服务器，将dynos减少到0，然后重新升级到1，然后运行$ heroku run psql -h HEROKU_POSTGRESQL_SILVER_URL -U deploy youmadlibs。我阅读了Heroku文档，用于将Ruby连接到数据库，而对于database.yml，它有host: localhost。我试过了（尽管它之前已经使用了我在下面的设置，我从教程中获取）。我还尝试了this tutorial的另一组database.yml设置。没有骰子！我在这里和其他地方读到了许多答案，无法弄清楚。如何重新建立数据库服务器连接？

database.yml中：

development:
  adapter: sqlite3
  database: db/madlibs.sqlite
  host: localhost
  pool: 5
  timeout: 5000

production:
  url: <%= ENV['DATABASE_URL'] %>
  adapter: postgresql
  database: mydb
  host: <%= ENV['DATABASE_HOST'] %>
  database: <%= ENV['DATABASE_NAME'] %>
  username: <%= ENV['DATABASE_USER'] %>
  password: <%= ENV['DATABASE_PASSWORD'] %>
  pool: 5
  timeout: 5000

.ENV：

DATABASE_URL=<...my database name...>

配置/ environment.rb中：

configure :development do
  set :database, {adapter: "sqlite3", database: "db/madlibs.sqlite3"}
  set :show_exceptions, true
end

configure :production do
  db = URI.parse(ENV['DATABASE_URL'] || 'postgres://localhost/mydb')

  ActiveRecord::Base.establish_connection(
      :adapter  => db.scheme == 'postgres' ? 'postgresql' : db.scheme,
      :host     => db.host,
      :username => db.user,
      :password => db.password,
      :database => db.path[1..-1],
      :encoding => 'utf8'
  )
end

的Gemfile：

source 'https://rubygems.org'
ruby '2.4.0'

gem 'sinatra', '2.0.1'
gem 'pg', '1.0.0'
gem 'activerecord', '5.2.0'
gem 'sinatra-activerecord', '2.0.13'
gem 'sinatra-flash', '0.3.0'                # Probably not nec.
gem 'sinatra-redirect-with-flash', '0.2.1'  # Probably not nec.
gem 'rake', '10.4.2'
gem 'rack', '2.0.3'
gem 'sass', '3.4.24'
gem 'json', '2.1.0'

group :development do
  gem 'sqlite3', '1.3.13'
  gem 'tux', '0.3.0'                        # Maybe unnec.
end

group :production do
end

app.rb的顶部：

require 'sinatra'
require 'sinatra/activerecord'
require './config/environment'
enable :sessions

class Madlib < ActiveRecord::Base
end

Answer 1

如果您有数据库网址，则不需要其他行，它可以是1行，也可以让postgres超时默认，不需要设置它。你可能想要更大的游泳池尺寸。转到你应该在Heroku中添加到你的应用程序的postgres数据库。单击View Credentials按钮。将数据从那里复制到您当地的.env文件，并将.env添加到您的.gitignore文件，因为您不想将您的私人凭据提交到您的公共存储库。

然后在heroku上

database.yml:

development:
  adapter: sqlite3
  database: db/madlibs.sqlite
  host: localhost
  pool: 5
  timeout: 5000

production: 
  adapter: postgresql
  encoding: unicode
  host: <%= ENV['DB_HOST'] %>
  username: <%= ENV['DB_USERNAME'] %>
  password: <%= ENV['DB_PASSWORD'] %>
  port: <%= ENV['DB_PORT'] %>
  database: <%= ENV['DB_NAME'] %>
  pool: 25

或者，您可以使用1个环境变量将所有这些连接成一个看起来像

的URI。

#postgresql://username:password@db-shared-us-east-1-or-something.blah:1234/db
#If you use this format you can use just a single environment variable somthinglike

production: 
  adapter: postgresql
  encoding: unicode
  url: <%= ENV['DATABASE_URI'] %>
  pool: 25

在任何一种情况下，您都需要设置您在Heroku仪表板中设置的database.yml文件中使用的任何环境变量：https://dashboard.heroku.com/apps/yourappname/settings并单击Reveal Config Vars。您可以在此处设置所需的变量，因为这是您的应用从中加载它们的位置。在我的第一个例子中设置vars，或者在我的第二个例子中设置一个vars。无论哪种方式都应该有效。

确保您在Gemfile中的生产组中拥有pg gem。并确保您已在heroku服务器上设置环境变量。

＆＃34; PG :: ConnectionBad - 无法连接到服务器：连接被拒绝＆＃34; Heroku上的Sinatra服务器

1 个答案: