Error when trying to install app with mysql2 gem

Question

Im trying to install an open source rails 3.2.21 application that uses the mysql2 gem, but when i try and run the bundle commant I get the following error:

Fetching: mysql2-0.3.18.gem (100%)
Building native extensions.  This could take a while...
p
ERROR:  Error installing mysql2:
    ERROR: Failed to build gem native extension.

    /Users/my_username/.rvm/rubies/ruby-2.1.2/bin/ruby -r ./siteconf20150614-72129-orqsb7.rb extconf.rb
checking for ruby/thread.h... yes
checking for rb_thread_call_without_gvl() in ruby/thread.h... yes
checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for rb_hash_dup()... yes
checking for rb_intern3()... yes
-----
Using mysql_config at /usr/local/bin/mysql_config
-----
checking for mysql.h... yes
checking for errmsg.h... yes
checking for mysqld_error.h... yes
-----
Don't know how to set rpath on your system, if MySQL libraries are not in path mysql2 may not load
-----
-----
Setting libpath to /usr/local/Cellar/mysql/5.6.25/lib
-----
creating Makefile

make "DESTDIR=" clean

make "DESTDIR="
compiling client.c
compiling infile.c
compiling mysql2_ext.c
compiling result.c
linking shared-object mysql2/mysql2.bundle
ld: warning: directory not found for option '-L/Users/travis/.sm/pkg/active/lib'
ld: library not found for -lssl
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [mysql2.bundle] Error 1

make failed, exit code 2

Gem files will remain installed in /Users/my_username/.rvm/rubies/ruby-2.1.2/lib/ruby/gems/2.1.0/gems/mysql2-0.3.18 for inspection.
Results logged to /Users/my_username/.rvm/rubies/ruby-2.1.2/lib/ruby/gems/2.1.0/extensions/x86

I tried uninstalling every version of mysql I installed via homebrew and reinstalling them, like so:

brew uninstall --force mysql && brew install mysql

Then running:

sudo gem install mysql2

As suggested by a number of similar questions asked on here, but it still results in the same error as above.

Please could someone offer guidance on how to get this up and running?

Answer 1

For anybody still experiencing the issue:

When you install openssl via brew, you should get the following message:

Apple has deprecated use of OpenSSL in favor of its own TLS and crypto libraries

Generally there are no consequences of this for you. If you build your own software and it requires this formula, you'll need to add to your build variables:

LDFLAGS: -L/usr/local/opt/openssl/lib
CPPFLAGS: -I/usr/local/opt/openssl/include
PKG_CONFIG_PATH: /usr/local/opt/openssl/lib/pkgconfig

You can set these build flags (for the local application) by running the following:

bundle config --local build.mysql2 "--with-ldflags=-L/usr/local/opt/openssl/lib --with-cppflags=-I/usr/local/opt/openssl/include"

This worked for me.

See bundler's documentation for more information.