bundle installで'ld: library not found for -lssl'が出てつらい話

ローカルにアプリケーションcloneしてきてrubyのデプロイツールを検証したい。

bundle installが通らない

$ bundle install --path vendor/bundle
Fetching mysql2 0.5.2
Installing mysql2 0.5.2 with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.
〜中略〜
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/hogehogeo/Documents/hogeo-service/vendor/bundle/ruby/2.6.0/gems/mysql2-0.5.2 for inspection.
Results logged to /Users/hogehogeo/Documents/hogeo-service/vendor/bundle/ruby/2.6.0/extensions/x86_64-darwin-18/2.6.0-static/mysql2-0.5.2/gem_make.out

An error occurred while installing mysql2 (0.5.2), and Bundler cannot continue.
Make sure that `gem install mysql2 -v '0.5.2' --source 'https://rubygems.org/'` succeeds before bundling.

gem installしてみる

gem install mysql2 -v '0.5.2' --source 'https://rubygems.org/

"ld: library not found for -lssl"で落ちる

$ gem install mysql2 
Building native extensions. This could take a while...
ERROR:  Error installing mysql2:
    ERROR: Failed to build gem native extension.
  
〜中略〜
current directory: /Users/hogehogeo/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/mysql2-0.5.2/ext/mysql2
make "DESTDIR="
compiling client.c
compiling infile.c
compiling mysql2_ext.c
compiling result.c
compiling statement.c
linking shared-object mysql2/mysql2.bundle
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/hogehogeo/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/mysql2-0.5.2 for inspection.
Results logged to /Users/hogehogeo/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/extensions/x86_64-darwin-18/2.6.0-static/mysql2-0.5.2/gem_make.out

参考：【Rails】MySQL2がbundle installできない時の対応方法 - Qiita

openssl自体は入ってるらしいので、upgradeしてみる

Error: openssl 1.0.2r is already installed
To upgrade to 1.0.2t, run `brew upgrade openssl`
$ brew upgrade openssl
==> Upgrading 1 outdated package:
openssl 1.0.2r -> 1.0.2t
==> Upgrading openssl 
==> Downloading https://homebrew.bintray.com/bottles/openssl-1.0.2t.mojave.bottle.tar.gz

中身見てみる

$ brew info openssl
openssl: stable 1.0.2t (bottled) [keg-only]
SSL/TLS cryptography library
https://openssl.org/
/usr/local/Cellar/openssl/1.0.2t (1,795 files, 12.0MB)
  Poured from bottle on 2019-09-25 at 12:18:20
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/openssl.rb
==> Caveats
A CA file has been bootstrapped using certificates from the SystemRoots
keychain. To add additional certificates (e.g. the certificates added in
the System keychain), place .pem files in
  /usr/local/etc/openssl/certs

and run
  /usr/local/opt/openssl/bin/c_rehash

openssl is keg-only, which means it was not symlinked into /usr/local,
because Apple has deprecated use of OpenSSL in favor of its own TLS and crypto libraries.

If you need to have openssl first in your PATH run:
  echo 'export PATH="/usr/local/opt/openssl/bin:$PATH"' >> ~/.bash_profile

For compilers to find openssl you may need to set:
  export LDFLAGS="-L/usr/local/opt/openssl/lib"
  export CPPFLAGS="-I/usr/local/opt/openssl/include"

For pkg-config to find openssl you may need to set:
  export PKG_CONFIG_PATH="/usr/local/opt/openssl/lib/pkgconfig"

==> Analytics
install: 268,610 (30 days), 1,333,944 (90 days), 6,296,651 (365 days)
install_on_request: 51,876 (30 days), 187,062 (90 days), 858,928 (365 days)
build_error: 0 (30 days)

上記を参考にしながらパスを指定

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

bundle install再実行

$ bundle install --path vendor/bundle
〜中略〜
Using mini_magick 4.9.5
Using mustermann 1.0.3
Fetching mysql2 0.5.2
Installing mysql2 0.5.2 with native extensions

通った。

もうやりたくない。