Gem::Ext::BuildError: ERROR: Failed to build gem native extension trying to install postgresql

Question

So I made my website with ruby-on-rails in Aws Cloud 9. I'm currently trying to deploy it with Heroku. A problem came up that I did all my coding with MySQLite3, which is not compatible with Heroku. So I changed my Gemfile to include 'pg', and ran bundle install and received a series of errors I'm unable to fix. Thanks in advance for your help.

My Gemfile:

source 'https://rubygems.org'


# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '~> 5.0.0'
# Use postgresql as the database for Active Record
gem 'pg', '1.1.4'
# Use Puma as the app server
gem 'puma', '~> 3.0'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 5.0'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .coffee assets and views
gem 'coffee-rails', '~> 4.2'
# See https://github.com/rails/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks
gem 'turbolinks', '~> 5'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.5'
# Use Redis adapter to run Action Cable in production
# gem 'redis', '~> 3.0'
# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use Devise for user authentication
gem 'devise'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platform: :mri
end

group :development do
  # Access an IRB console on exception pages or by using <%= console %> anywhere in the code.
  gem 'web-console'
  gem 'listen', '~> 3.0.5'
  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
end

# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

The error:

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.

So I try:

gem install pg -v '1.1.4' --source 'https://rubygems.org/'

Error:

To see why this extension failed to compile, please check the mkmf.log which can be found here:

  /home/ec2-user/.rvm/gems/ruby-2.6.3/extensions/x86_64-linux/2.6.0/pg-1.1.4/mkmf.log

Inside mkmf.log:

find_executable: checking for pg_config... -------------------- no

--------------------

find_header: checking for libpq-fe.h... -------------------- no

"gcc -o conftest -I/home/ec2-user/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0/x86_64-linux -I/home/ec2-user/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0/ruby/backward -I/home/ec2-user/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0 -I.    -O3 -ggdb3 -Wall -Wextra -Wdeclaration-after-statement -Wdeprecated-declarations -Wimplicit-function-declaration -Wimplicit-int -Wpointer-arith -Wwrite-strings -Wmissing-noreturn -Wno-cast-function-type -Wno-constant-logical-operand -Wno-long-long -Wno-missing-field-initializers -Wno-overlength-strings -Wno-packed-bitfield-compat -Wno-parentheses-equality -Wno-self-assign -Wno-tautological-compare -Wno-unused-parameter -Wno-unused-value -Wsuggest-attribute=format -Wsuggest-attribute=noreturn -Wunused-variable  -fPIC conftest.c  -L. -L/home/ec2-user/.rvm/rubies/ruby-2.6.3/lib -Wl,-rpath,/home/ec2-user/.rvm/rubies/ruby-2.6.3/lib -L. -fstack-protector-strong -rdynamic -Wl,-export-dynamic     -Wl,-rpath,/home/ec2-user/.rvm/rubies/ruby-2.6.3/lib -L/home/ec2-user/.rvm/rubies/ruby-2.6.3/lib -lruby  -lm   -lc"
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/home/ec2-user/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0/x86_64-linux -I/home/ec2-user/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0/ruby/backward -I/home/ec2-user/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0 -I.    -O3 -ggdb3 -Wall -Wextra -Wdeclaration-after-statement -Wdeprecated-declarations -Wimplicit-function-declaration -Wimplicit-int -Wpointer-arith -Wwrite-strings -Wmissing-noreturn -Wno-cast-function-type -Wno-constant-logical-operand -Wno-long-long -Wno-missing-field-initializers -Wno-overlength-strings -Wno-packed-bitfield-compat -Wno-parentheses-equality -Wno-self-assign -Wno-tautological-compare -Wno-unused-parameter -Wno-unused-value -Wsuggest-attribute=format -Wsuggest-attribute=noreturn -Wunused-variable  -fPIC  conftest.c -o conftest.i"
conftest.c:3:22: fatal error: libpq-fe.h: No such file or directory
 #include <libpq-fe.h>
                      ^
compilation terminated.
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
/* end */

--------------------

I did some looking around and found I should run sudo apt-get install libpq-dev. In aws Cloud 9, that becomes sudo yum install libpq-dev. That gives the error:

Loaded plugins: priorities, update-motd, upgrade-helper
amzn-main                                                                                                                                                            | 2.1 kB  00:00:00     
amzn-updates                                                                                                                                                         | 2.5 kB  00:00:00     
1065 packages excluded due to repository priority protections
No package libpq-dev available.
Error: Nothing to do

Loaded plugins: priorities, update-motd, upgrade-helper amzn-main | 2.1 kB 00:00:00
amzn-updates | 2.5 kB 00:00:00
1065 packages excluded due to repository priority protections No package libpq-dev available. Error: Nothing to do

What's the problem here?

Answer 1

Because you're using the yum package manager, the package name is wrong. libpq-dev is the package name for the apt package manager. Try installing postgresql-libs . If that doesn't work, try postgresql-devel .