ruby-on-rails - Postgres 无法连接到服务器

Question

为什么 Postgres 没有在我刚开始的新应用程序上工作，这让我感到非常困惑。我已经让它适用于一个应用程序。我正在使用 postgres.app，它正在运行。

我开始了一个新的应用程序

rails new depot -d postgresql

然后我进入 database.yml 文件并将用户名更改为我的 $USER （这是另一个正在运行的应用程序的内容）。所以现在我的 database.yml 文件有这个开发部分：

development:
  adapter: postgresql
  encoding: unicode
  database: depot_development
  pool: 5
  username: <username>
  password:

但是当我运行“rake db:create”或“rake db:create:all”时，我仍然得到这个错误（完全，因为我不知道什么是相关的）：

Couldn't create database for {"adapter"=>"postgresql", "encoding"=>"unicode", "database"=>"depot_development", "pool"=>5, "username"=>"<username>", "password"=>nil}
could not connect to server: Permission denied
    Is the server running locally and accepting
    connections on Unix domain socket "/var/pgsql_socket/.s.PGSQL.5432"?
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/postgresql_adapter.rb:1213:in `initialize'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/postgresql_adapter.rb:1213:in `new'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/postgresql_adapter.rb:1213:in `connect'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/postgresql_adapter.rb:329:in `initialize'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/postgresql_adapter.rb:28:in `new'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/postgresql_adapter.rb:28:in `postgresql_connection'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:309:in `new_connection'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:319:in `checkout_new_connection'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:241:in `block (2 levels) in checkout'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:236:in `loop'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:236:in `block in checkout'
/Users/<username>/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:233:in `checkout'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:96:in `block in connection'
/Users/<username>/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:95:in `connection'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:404:in `retrieve_connection'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_specification.rb:170:in `retrieve_connection'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_specification.rb:144:in `connection'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/railties/databases.rake:107:in `rescue in create_database'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/railties/databases.rake:51:in `create_database'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/railties/databases.rake:40:in `block (3 levels) in <top (required)>'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/railties/databases.rake:40:in `each'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/gems/activerecord-3.2.8/lib/active_record/railties/databases.rake:40:in `block (2 levels) in <top (required)>'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `call'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `block in execute'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `each'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `execute'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/task.rb:158:in `block in invoke_with_call_chain'
/Users/<username>/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/task.rb:144:in `invoke'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:116:in `invoke_task'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block (2 levels) in top_level'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `each'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block in top_level'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:88:in `top_level'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:66:in `block in run'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/gems/rake-0.9.2.2/bin/rake:33:in `<top (required)>'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/bin/rake:19:in `load'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194@global/bin/rake:19:in `<main>'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `eval'
/Users/<username>/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `<main>'
Couldn't create database for {"adapter"=>"postgresql", "encoding"=>"unicode", "database"=>"depot_test", "pool"=>5, "username"=>"<username>", "password"=>nil}

我试过了

createdb depot_development

我尝试进入 psql 环境并列出用户（其中​​包括我的用户名）。在同一个psql环境下，我试过了

CREATE DATABASE depot;

I've made sure that the pg gem is installed with bundle install, I've run "pg_ctl start", to which I got this response:

pg_ctl: no database directory specified and environment variable PGDATA unset

I ran "ps aux | grep postgres" to make sure postgres was running, to which I got this in return (which looks like it's doing OK, right?):

<username>    10390   0.4  0.0  2425480    180 s000  R+    6:15PM   0:00.00 grep postgres
<username>     2907   0.0  0.0  2441604    464   ??  Ss    6:17PM   0:02.31 postgres: stats collector process      
<username>     2906   0.0  0.0  2445520   1664   ??  Ss    6:17PM   0:02.33 postgres: autovacuum launcher process      
<username>     2905   0.0  0.0  2445388    600   ??  Ss    6:17PM   0:09.25 postgres: wal writer process      
<username>     2904   0.0  0.0  2445388   1252   ??  Ss    6:17PM   0:12.08 postgres: writer process      
<username>     2902   0.0  0.0  2445388   3688   ??  S     6:17PM   0:00.54 /Applications/Postgres.app/Contents/MacOS/bin/postgres -D /Users/<username>/Library/Application Support/Postgres/var -p5432

The short of it, is I've been troubleshooting for a WHILE and have NO idea what's wrong. Any ideas? I'd really appreciate it, cause I'm pretty new to Rails, and this is a pretty disheartening roadblock.

Thanks!

EDIT -- Per request, posting the successful database.yml . It seems the difference is the inclusion of a password:

development:
  adapter: postgresql
  encoding: unicode
  database: *******_development
  pool: 5
  username: *******
  password: *******

EDIT2 -- When I add a password to the .yml file, then run rake db:create again, I get the same error. And I'm running Mac OSX Lion, and I did initdb and stuff when I first installed PostgreSQL.

Answer 1

In order to create a database , before starting the command pg_ctl start

• you have to initialize the database cluster then only pg_ctl start shall be success full*

this can be done in many ways if you are running on Linux / centos with postgres 9.1

service postgresql-9.1 initdb

service  postgresql-9.1 start

or you can do like this

$ mkdir -p /var/pgsql/data; chown -R postgres /var/pgsql
$ su - postgres
$ initdb -D /var/pgsql/data

# Starting, testing:

$ postgres -D /var/pgsql/data > /var/pgsql/logfile 2>&1 &
$ createdb test
$ psql test

Initializing postgres initb differes from os to os and postgres versions , if the above command did not work please have a look at

Answer 2

Adding

host: localhost

to development works for me.