我使用的是Ruby on Rails 3.1预版本。我喜欢使用PostgreSQL,但问题是安装pg gem。它给了我以下错误:

$ gem install pg
Building native extensions.  This could take a while...
ERROR:  Error installing pg:
    ERROR: Failed to build gem native extension.

        /home/u/.rvm/rubies/ruby-1.9.2-p0/bin/ruby extconf.rb
checking for pg_config... no
No pg_config... trying anyway. If building fails, please try again with
 --with-pg-config=/path/to/pg_config
checking for libpq-fe.h... no
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.

Provided configuration options:
    --with-opt-dir
    --without-opt-dir
    --with-opt-include
    --without-opt-include=${opt-dir}/include
    --with-opt-lib
    --without-opt-lib=${opt-dir}/lib
    --with-make-prog
    --without-make-prog
    --srcdir=.
    --curdir
    --ruby=/home/u/.rvm/rubies/ruby-1.9.2-p0/bin/ruby
    --with-pg
    --without-pg
    --with-pg-dir
    --without-pg-dir
    --with-pg-include
    --without-pg-include=${pg-dir}/include
    --with-pg-lib
    --without-pg-lib=${pg-dir}/lib
    --with-pg-config
    --without-pg-config
    --with-pg_config
    --without-pg_config
    Gem files will remain installed in /home/u/.rvm/gems/ruby-1.9.2-p0/gems/pg-0.11.0 for inspection.
    Results logged to /home/u/.rvm/gems/ruby-1.9.2-p0/gems/pg-0.11.0/ext/gem_make.out

我怎么解决这个问题?


当前回答

我刚刚在OSX上运行了brew和postgres@9.4。

我的解决方案是这样的:

CONFIGURE_ARGS="with-pg-include=/usr/local/opt/postgresql@9.4/include/" bundle install

其他回答

在OS X 10.9 (Mavericks)上,我自定义安装了postgresql,然后我必须rvm重新安装Ruby。我现在很开心:)

我在亚马逊Linux上也遇到了同样的问题。我可以找到libpq-fe.h头文件,但不知为何它不起作用。

它来自不同用户在机器上安装的不同版本的软件包。安装PostgreSQL 9.2和PostgreSQL 9.3。因此,在包含库之前,请确保您的PostgreSQL版本。

对我来说,神奇的命令行是:

sudo yum install postgresql93 postgresql93-server postgresql93-libs postgresql93-contrib postgresql93-devel

资料来源:用Yum安装PostgreSQL 9.3、PostGIS 2.1和p注浆的白痴指南

Mac用户使用Postgres的正确答案。应用程序是根据该包提供的libpq构建的。例如,对于9.4版本(撰写本文时的最新版本),您所需要的是:

export CONFIGURE_ARGS="with-pg-include=/Applications/Postgres.app/Contents/Versions/9.4/include"
gem install pg

这将使你的pg gem与你安装的PostgreSQL版本保持同步。在这种情况下,安装Homebrew软件是一种浪费。

在Mac上,我用下面的代码解决了这个问题:

gem install pg -v '0.18.4' -- --with-pg-config=/Applications/Postgres.app/Contents/Versions/9.4/bin/pg_config

在OS X和MacPorts上,PostgreSQL不再需要-devel包。安装pg gem的步骤如下:

~ > sudo port install postgresql-devel
...
Error: postgresql-devel has been replaced by postgresql91; please install that port instead
~ > gem install pg -v '0.17.1' -- --with-pg-config=/opt/local/lib/postgresql95/bin/pg_config

参见这篇文章。