在Heroku – Rails中安装gem’pg’的问题

我正在尝试在OSX上的rails上安装ruby for heroku ，为此我使用了本教程 。 它似乎在终端上安装得很好，但在做完之后

$rails new myapp --database=postgresql cd myapp 

我这样做了

 rails generate controller welcome 

并得到一个错误：

Could not find gem 'spring (>= 0) ruby' in the gems available on this machine. Run Could not find gem 'spring (>= 0) ruby' in the gems available on this machine. Run bundle install to install missing gems.

遵照说明后，我得到了

 'An error occurred while installing pg (0.17.1), and Bundler cannot continue. Make sure that `gem install pg -v '0.17.1'` succeeds before bundling.' 

然后…

 ERROR: Error installing pg: ERROR: Failed to build gem native extension. ... Can't find the 'libpq-fe.h header *** extconf.rb failed *** Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options. 

一个类似的SO问题说通过更新XCode解决了问题，但我不认为这是我的问题。 如果还不是很明显，我对终端或ruby不是很有经验，所以我不确定如何解决这个问题。

编辑：

新的错误消息

 Gem::Ext::BuildError: ERROR: Failed to build gem native extension. /Users/mahireusufzai/.rbenv/versions/2.1.1/bin/ruby extconf.rb checking for pg_config... yes Using config values from /usr/local/bin/pg_config *** extconf.rb failed *** Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options. 

…

 /Users/mahireusufzai/.rbenv/versions/2.1.1/lib/ruby/2.1.0/mkmf.rb:456:in `try_do': The compiler failed to generate an executable file. (RuntimeError) You have to install development tools first. from /Users/mahireusufzai/.rbenv/versions/2.1.1/lib/ruby/2.1.0/mkmf.rb:541:in `try_link0' from /Users/mahireusufzai/.rbenv/versions/2.1.1/lib/ruby/2.1.0/mkmf.rb:556:in `try_link' from extconf.rb:39:in `' extconf failed, exit code 1 Gem files will remain installed in /Users/mahireusufzai/.rbenv/versions/2.1.1/lib/ruby/gems/2.1.0/gems/pg-0.17.1 for inspection. 

Answer 1

您需要先安装postgresql开发库。 它抱怨libpq-fe.h丢失了。

尝试按照以下post中的答案解决： Rails：安装pg gem时出错

Answer 2

尝试

 yum install postgresql-devel 

要么

 brew install postgresql 

那么gem install pg应该可行