问题
I'm trying to install mysql2 gem with ruby on rails 4/ruby 2.0 OpenShift scaled app. But, bundle install fails, trying "gem install mysql2", which leads to the following error:
gem install mysql2
Fetching: mysql2-0.4.1.gem (100%)
Building native extensions. This could take a while...
ERROR: Error installing mysql2:
ERROR: Failed to build gem native extension.
/opt/rh/ruby200/root/usr/bin/ruby 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 /opt/rh/mysql55/root/usr/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 /opt/rh/mysql55/root/usr/lib64/mysql
-----
creating Makefile
make "DESTDIR="
gcc -I. -I/opt/rh/ruby200/root/usr/include -I/opt/rh/ruby200/root/usr/include/ruby/backward -I/opt/rh/ruby200/root/usr/include -I. -I/opt/rh/mysql55/root/usr/include/mysql -DHAVE_RUBY_THREAD_H -DHAVE_RB_THREAD_CALL_WITHOUT_GVL -DHAVE_RB_THREAD_BLOCKING_REGION -DHAVE_RB_WAIT_FOR_SINGLE_FD -DHAVE_RB_HASH_DUP -DHAVE_RB_INTERN3 -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H -fPIC -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -mtune=generic -fPIC -m64 -o client.o -c client.c
gcc -I. -I/opt/rh/ruby200/root/usr/include -I/opt/rh/ruby200/root/usr/include/ruby/backward -I/opt/rh/ruby200/root/usr/include -I. -I/opt/rh/mysql55/root/usr/include/mysql -DHAVE_RUBY_THREAD_H -DHAVE_RB_THREAD_CALL_WITHOUT_GVL -DHAVE_RB_THREAD_BLOCKING_REGION -DHAVE_RB_WAIT_FOR_SINGLE_FD -DHAVE_RB_HASH_DUP -DHAVE_RB_INTERN3 -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H -fPIC -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -mtune=generic -fPIC -m64 -o infile.o -c infile.c
gcc -I. -I/opt/rh/ruby200/root/usr/include -I/opt/rh/ruby200/root/usr/include/ruby/backward -I/opt/rh/ruby200/root/usr/include -I. -I/opt/rh/mysql55/root/usr/include/mysql -DHAVE_RUBY_THREAD_H -DHAVE_RB_THREAD_CALL_WITHOUT_GVL -DHAVE_RB_THREAD_BLOCKING_REGION -DHAVE_RB_WAIT_FOR_SINGLE_FD -DHAVE_RB_HASH_DUP -DHAVE_RB_INTERN3 -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H -fPIC -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -mtune=generic -fPIC -m64 -o mysql2_ext.o -c mysql2_ext.c
gcc -I. -I/opt/rh/ruby200/root/usr/include -I/opt/rh/ruby200/root/usr/include/ruby/backward -I/opt/rh/ruby200/root/usr/include -I. -I/opt/rh/mysql55/root/usr/include/mysql -DHAVE_RUBY_THREAD_H -DHAVE_RB_THREAD_CALL_WITHOUT_GVL -DHAVE_RB_THREAD_BLOCKING_REGION -DHAVE_RB_WAIT_FOR_SINGLE_FD -DHAVE_RB_HASH_DUP -DHAVE_RB_INTERN3 -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H -fPIC -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -mtune=generic -fPIC -m64 -o result.o -c result.c
gcc -I. -I/opt/rh/ruby200/root/usr/include -I/opt/rh/ruby200/root/usr/include/ruby/backward -I/opt/rh/ruby200/root/usr/include -I. -I/opt/rh/mysql55/root/usr/include/mysql -DHAVE_RUBY_THREAD_H -DHAVE_RB_THREAD_CALL_WITHOUT_GVL -DHAVE_RB_THREAD_BLOCKING_REGION -DHAVE_RB_WAIT_FOR_SINGLE_FD -DHAVE_RB_HASH_DUP -DHAVE_RB_INTERN3 -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H -fPIC -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -mtune=generic -fPIC -m64 -o statement.o -c statement.c
rm -f mysql2.so
gcc -shared -o mysql2.so client.o infile.o mysql2_ext.o result.o statement.o -L. -L/opt/rh/ruby200/root/usr/lib64 -L/opt/rh/mysql55/root/usr/lib64/mysql -L. -fstack-protector -rdynamic -Wl,-export-dynamic -m64 -lruby -L/opt/rh/mysql55/root/usr/lib64/mysql -lmysqlclient -lpthread -lz -lm -lrt -lssl -lcrypto -ldl -lpthread -lrt -ldl -lcrypt -lm -lc
/usr/bin/ld: cannot find -lmysqlclient
collect2: ld returned 1 exit status
make: *** [mysql2.so] Error 1
Gem files will remain installed in /var/lib/openshift/541424415004469f3a000b85/.gem/gems/mysql2-0.4.1 for inspection.
Results logged to /var/lib/openshift/541424415004469f3a000b85/.gem/gems/mysql2-0.4.1/ext/mysql2/gem_make.out
MySQL libraries/SDK are supposed to be maintained/provided by RedHat in the PaaS offering, so I'm a bit stuck. Interestingly enough, until tonight, it worked well.
EDIT: The first answers revealed, that I missed an important point in the question. In OpenShift one does not have root access to the gear, so I cannot execute yum install as suggested below. It is really an OpenShift specific question, not a general one. I definitely know how to install MySQL development libraries. Sorry about the confusion, caused by the missing piece of information.
回答1:
On Mac OS X, and is using Homebrew:
brew install mysql
or if you're on Red Hat or CentOS or other distributions using yum:
sudo yum install mysql-devel
and finally, if you're on Ubuntu or Debian or other distributions using aptitude:
sudo apt-get install libmysqlclient-dev
回答2:
Ok, I finally made it and I'm posting the answer so that others can benefit from that in case they meet the same problem.
The reason for the behavior was apparently that the previous deployment approach in OpenShift broke in the middle, which left the gear in an inconsistent state (the issue with mysql2 gem was one symptom of that). What I basically tried to do is to bring it back to a consistent state manually by bundle'ing and re-building from the git HEAD.
This did not work.
Attempts to push to the gear git from my development repository did not work either, since nothing has changed from the last push (which resulted in deployment that broke apparently due to some OpenShift internal bugs).
What I did at the end, I made some change in the bundle (in my case updated one gem by bundle update) and this updated Gemfile.lock.
Since I also checked in "force_clean_build" marker, the subsequent push rebuilt the gear from scratch, also having brought it to a consistent state.
Long story short, if OpenShift deployment breaks in the middle, it is much better to make a fake change in sources and push them in conjunction with the marker force_clean_build to the gear's git than to try to rebuild manually by gear deploy HEAD, since the latter does not clean up the possibly occurred inconsistency.
来源：https://stackoverflow.com/questions/32813780/cannot-install-mysql2-gem-on-openshift-scaled-app