Library not loaded: /usr/local/o

家里电脑好久没用，安装cocoapods时报错，应该是本地的openssl升级了导致的

➜  ~ sudo gem install cocoapods
Password:
ERROR:  Loading command: install (LoadError)
    dlopen(/usr/local/Cellar/ruby/2.4.1_1/lib/ruby/2.4.0/x86_64-darwin16/openssl.bundle, 9): Library not loaded: /usr/local/opt/openssl/lib/libssl.1.0.0.dylib
  Referenced from: /usr/local/Cellar/ruby/2.4.1_1/lib/ruby/2.4.0/x86_64-darwin16/openssl.bundle
  Reason: image not found - /usr/local/Cellar/ruby/2.4.1_1/lib/ruby/2.4.0/x86_64-darwin16/openssl.bundle
ERROR:  While executing gem ... (NoMethodError)
    undefined method `invoke_with_build_args' for nil:NilClass

解决办法：切换openssl 版本

brew switch openssl 1.0.2m