Improve Homebrew compatibility

[stefansundin]

Hi!

When I develop on my Mac, I usually install the Homebrew package mysql-client instead of mysql, since I don't really need the server (I usually run that in Docker). But unfortunately mysql2 doesn't compile out of the box.

I have worked around it by first running:

bundle config build.mysql2 --with-mysql-dir="/usr/local/opt/mysql-client"

But now I decided to look into contributing a fix.

Hopefully this will be accepted and included in the next version. Thanks!

[sodabrew]

Looks good to me!

[sodabrew]

Where does the mysql-server package install in Homebrew? The list of paths may be a bit out of date at this point, given MySQL 8 being the primary version to use now.

[stefansundin]

It looks like with mysql, it finds /usr/local/bin/mysql_config and uses that. I am going to run some more testing to try to make this gem more compatible with different macOS setups. There isn't a separate mysql-server package for the server, so the mysql package installs both the server and the client.

I don't have the full Xcode installed, so I was having some issues with linking openssl with the mysql package.

ld: library not found for -lssl

I was able to fix it by adding $LDFLAGS << " -L/usr/local/opt/openssl/lib" to extconf.rb. Not sure if there's a better way. Not sure why this didn't happen with mysql-client.

I also realized that there's a [email protected] package. There's also [email protected] and [email protected]. I can add more search paths until it works with all of the combinations.

$ brew search mysql | cat
==> Formulae
automysqlbackup
mysql
mysql++
mysql-client
[email protected]
mysql-connector-c++
[email protected]
mysql-sandbox
mysql-search-replace
[email protected]
[email protected]
mysqltuner
==> Casks
mysql-connector-python
mysql-shell
mysql-utilities
mysqlworkbench
navicat-for-mysql
sqlpro-for-mysql

(used cat to just get one entry per line, like ls -1)

I will do some more testing and report back.

[stefansundin]

This explains the -lssl issue. For some reason there are libssl files that comes with mysql-client but not mysql.

$ /usr/local/bin/mysql_config --libs
-L/usr/local/Cellar/mysql/8.0.21_1/lib -lmysqlclient -lssl -lcrypto
$ /usr/local/opt/mysql-client/bin/mysql_config --libs
-L/usr/local/opt/mysql-client/lib -lmysqlclient -lssl -lcrypto
$ ls -1 /usr/local/Cellar/mysql/8.0.21_1/lib
libmysqlclient.21.dylib
libmysqlclient.a
libmysqlclient.dylib
libmysqlharness.1.dylib
libmysqlrouter.1.dylib
libmysqlrouter_http.1.dylib
libmysqlrouter_http_auth_backend.1.dylib
libmysqlrouter_http_auth_realm.1.dylib
libmysqlservices.a
mysqlrouter
pkgconfig
plugin
$ ls -1 /usr/local/opt/mysql-client/lib
libcrypto.1.1.dylib
libcrypto.dylib
libmysqlclient.21.dylib
libmysqlclient.a
libmysqlclient.dylib
libssl.1.1.dylib
libssl.dylib
pkgconfig
plugin

It may be because mysql sets -DWITH_SSL=#{Formula["[email protected]"].opt_prefix} while mysql-client sets -DWITH_SSL=yes.

Edit: It deletes a bunch of libssl files too, so maybe that's the actual reason. https://github.com/Homebrew/homebrew-core/blob/9e4e4f9c53e83d5ff555f6faaa2afc7f72266f13/Formula/mysql.rb#L72-L78

If you are ok with it, I think we should add something like this:

if RUBY_PLATFORM =~ /darwin/
  $LDFLAGS << ' -L/usr/local/opt/openssl/lib'
end

I imagine that plenty of Rubyists may be installing full Xcode to get this gem to work.

[stefansundin]

I added two more commits. Let me know if you just want me to change /usr/local/opt/mysql@* to /usr/local/opt/mysql* instead, as that should catch a lot of paths. And let me know if you want me to squash the commits (or you can do it when you merge).

Thanks!

[sodabrew]

All good, will squash and merge!

[olivierlacan]

Hey @stefansundin. Unless I'm mistaken there's no openssl recipe for Homebrew, only https://formulae.brew.sh/formula/[email protected]#default which doesn't install in /openssl/ anymore:

$ brew --prefix openssl
/opt/homebrew/opt/[email protected]

Homebrew itself recommends this flag:

For compilers to find [email protected] you may need to set:
  export LDFLAGS="-L/opt/homebrew/opt/[email protected]/lib"
  export CPPFLAGS="-I/opt/homebrew/opt/[email protected]/include"

So at the risk of slowing things down a bit it might be good to ask Homebrew if it's installed and then ask it where openssl is installed if at all. Something like:

brew_installed = system("command -v brew") 
if brew_installed # because brew --prefix would explode otherwise
  openssl_location = `brew --prefix openssl`.strip # because output includes \n character
  $LDFLAGS << " -L#{openssl_location}/lib" if RUBY_PLATFORM =~ /darwin/ && openssl_location
end

I'll gladly submit a follow-up PR if this seems reasonable.

[stefansundin]

@olivierlacan Sounds reasonable to me!