gem install pg for ruby on rails - ruby-on-rails

Question

Postgresql will not install on OSX
here is my data below
n error occurred while installing pg (0.18.4), and Bundler cannot continue.
Make sure that gem install pg -v '0.18.4' succeeds before bundling.
chriss-MacBook-Pro:shine chriswilson$ bundle exec install
usage: install [-bCcpSsv] [-B suffix] [-f flags] [-g group] [-m mode]
[-o owner] file1 file2
install [-bCcpSsv] [-B suffix] [-f flags] [-g group] [-m mode]
[-o owner] file1 ... fileN directory
install -d [-v] [-g group] [-m mode] [-o owner] directory ...
chriss-MacBook-Pro:shine chriswilson$ gem install pg -v '0.18.4'
Building native extensions. This could take a while...
ERROR: Error installing pg:
ERROR: Failed to build gem native extension.
current directory: /Users/chriswilson/.rvm/gems/ruby-2.3.0/gems/pg-0.18.4/ext
/Users/chriswilson/.rvm/rubies/ruby-2.3.0/bin/ruby -r ./siteconf20160902-1617-e1qwb1.rb 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
--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=/Users/chriswilson/.rvm/rubies/ruby-2.3.0/bin/$(RUBY_BASE_NAME)
--with-pg
--without-pg
--enable-windows-cross
--disable-windows-cross
--with-pg-config
--without-pg-config
--with-pg_config
--without-pg_config
--with-pg-dir
--without-pg-dir
--with-pg-include
--without-pg-include=${pg-dir}/include
--with-pg-lib
--without-pg-lib=${pg-dir}/lib
To see why this extension failed to compile, please check the mkmf.log which can be found here:
/Users/chriswilson/.rvm/gems/ruby-2.3.0/extensions/x86_64-darwin-15/2.3.0/pg-0.18.4/mkmf.log
extconf failed, exit code 1
Gem files will remain installed in /Users/chriswilson/.rvm/gems/ruby-2.3.0/gems/pg-0.18.4 for inspection.
Results logged to /Users/chriswilson/.rvm/gems/ruby-2.3.0/extensions/x86_64-darwin-15/2.3.0/pg-0.18.4/gem_make.out
chriss-MacBook-Pro:shine chriswilson$ gem install pg -v '0.18.4'
Building native extensions. This could take a while...
ERROR: Error installing pg:
ERROR: Failed to build gem native extension.
current directory: /Users/chriswilson/.rvm/gems/ruby-2.3.0/gems/pg-0.18.4/ext
/Users/chriswilson/.rvm/rubies/ruby-2.3.0/bin/ruby -r ./siteconf20160902-1643-jfhxyo.rb 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
--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=/Users/chriswilson/.rvm/rubies/ruby-2.3.0/bin/$(RUBY_BASE_NAME)
--with-pg
--without-pg
--enable-windows-cross
--disable-windows-cross
--with-pg-config
--without-pg-config
--with-pg_config
--without-pg_config
--with-pg-dir
--without-pg-dir
--with-pg-include
--without-pg-include=${pg-dir}/include
--with-pg-lib
--without-pg-lib=${pg-dir}/lib
To see why this extension failed to compile, please check the mkmf.log which can be found here:
/Users/chriswilson/.rvm/gems/ruby-2.3.0/extensions/x86_64-darwin-15/2.3.0/pg-0.18.4/mkmf.log
extconf failed, exit code 1
Gem files will remain installed in /Users/chriswilson/.rvm/gems/ruby-2.3.0/gems/pg-0.18.4 for inspection.
Results logged to /Users/chriswilson/.rvm/gems/ruby-2.3.0/extensions/x86_64-darwin-15/2.3.0/pg-0.18.4/gem_make.out
find_executable: checking for pg_config... -------------------- no
--------------------
find_header: checking for libpq-fe.h... -------------------- no
"gcc -o conftest -I/Users/chriswilson/.rvm/rubies/ruby-2.3.0/include/ruby-2.3.0/x86_64-darwin15 -I/Users/chriswilson/.rvm/rubies/ruby-2.3.0/include/ruby-2.3.0/ruby/backward -I/Users/chriswilson/.rvm/rubies/ruby-2.3.0/include/ruby-2.3.0 -I. -I/usr/local/opt/libyaml/include -I/usr/local/opt/readline/include -I/usr/local/opt/libksba/include -I/usr/local/opt/openssl/include -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -D_DARWIN_UNLIMITED_SELECT -D_REENTRANT -O3 -fno-fast-math -ggdb3 -Wall -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Wunused-variable -Wpointer-arith -Wwrite-strings -Wdeclaration-after-statement -Wshorten-64-to-32 -Wimplicit-function-declaration -Wdivision-by-zero -Wdeprecated-declarations -Wextra-tokens -fno-common -pipe conftest.c -L. -L/Users/chriswilson/.rvm/rubies/ruby-2.3.0/lib -L/usr/local/opt/libyaml/lib -L/usr/local/opt/readline/lib -L/usr/local/opt/libksba/lib -L/usr/local/opt/openssl/lib -L. -fstack-protector -L/usr/local/lib -L/usr/local/opt/libyaml/lib -L/usr/local/opt/readline/lib -L/usr/local/opt/libksba/lib -L/usr/local/opt/openssl/lib -lruby.2.3.0 -lpthread -ldl -lobjc "
checked program was:
/* begin */
1: #include "ruby.h"
2:
3: int main(int argc, char **argv)
4: {
5: return 0;
6: }
/* end */
"gcc -E -I/Users/chriswilson/.rvm/rubies/ruby-2.3.0/include/ruby-2.3.0/x86_64-darwin15 -I/Users/chriswilson/.rvm/rubies/ruby-2.3.0/include/ruby-2.3.0/ruby/backward -I/Users/chriswilson/.rvm/rubies/ruby-2.3.0/include/ruby-2.3.0 -I. -I/usr/local/opt/libyaml/include -I/usr/local/opt/readline/include -I/usr/local/opt/libksba/include -I/usr/local/opt/openssl/include -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -D_DARWIN_UNLIMITED_SELECT -D_REENTRANT -O3 -fno-fast-math -ggdb3 -Wall -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Wunused-variable -Wpointer-arith -Wwrite-strings -Wdeclaration-after-statement -Wshorten-64-to-32 -Wimplicit-function-declaration -Wdivision-by-zero -Wdeprecated-declarations -Wextra-tokens -fno-common -pipe conftest.c -o conftest.i"
conftest.c:3:10: fatal error: 'libpq-fe.h' file not found
#include <libpq-fe.h>
^
1 error generated.
checked program was:
/* begin */
1: #include "ruby.h"
2:
3: #include <libpq-fe.h>
/* end */
--------------------

Answer 1

This basically means that you're missing a library or program on your setup. I've had this issue a couple of times now so here are a few different things to try (hopefully one of them will work for you):
Install a common missing library:
brew install libpqxx
gem install pg
Reinstall postgres (not ideal I know):
brew uninstall postgresql
brew install postgresql
gem install pg
Explicitly define path of pg_config:
1) Get location of pg_config
which pg_config
2) pass that path into gem install
gem install pg --with-pg-config=/usr/pgsql-9.1/bin/pg_config

Answer 2

Try this it will work
sudo apt-get install -y libpq-dev build-essential postgresql-server-dev-all libpgsql-ruby postgresql ruby-dev && gem install pg