How do I get postgresql to work in my local environment? I want to build and deploy to heroku.

Question

I am on El Capitan 10.11.6 and using bash. ruby 2.3.0 rails 5.0.0

I have been learning ruby/rails and would like to push an app up to heroku. I have followed the steps outlined by the heroku documentation and Postgres.app documentation.

I downloaded Postgres.app and moved it to the Applications directory.

I placed this in my ~/.bash_profile
export PATH=$PATH:/Applications/Postgres.app/Contents/Versions/9.5/bin

Yet when I type in $ which psql I get no info at all. Also, $ psql -h loclhost does nothing. I can however, "start" Postgres.app by double clicking on the icon, and I get the elephant in the menu bar.

Furthermore, I can not install gem 'pg'. I get the error:

Installing pg 0.18.4 with native extensions

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

current directory: /Users/jesselawson/.rvm/gems/ruby-2.3.0/gems/pg-       0.18.4/ext
/Users/jesselawson/.rvm/rubies/ruby-2.3.0/bin/ruby -r  ./siteconf20160821-1410-1o4aen1.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. 

and

An 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.

Answer 1

Ok so shortly after I posted the question, I found the answer. Because I downloaded and am using the Postgres.app, I have to have to app running by double clicking the icon. Then in the terminal I can access the cli. Interacting with the pg database can not be done unless the app is running. To have access without the app running I would have to install via homebrew. In which case it would prob. make sense to remove the Postgres.app due to user_name issues, and to minimize spooky action, and my general confusion. (stick with one or the other) Once I started the Postgres.app I could then also run bundle install and gem 'pg' installed just fine. Thank you all for all the help! :)

Answer 2

As stated in your error message, you should try to install the gem first, without the use of bundler.

Try the following command in your console:

gem install pg -- --with-pg-config=/Applications/Postgres.app/Contents/Versions/9.5/bin/pg_config

In case you still have troube, try the following resources:

• Cannot install pg gem in Mavericks with Postgres.app
• An error occurred while installing pg (0.17.1), and Bundler cannot continue