cocoapods 不能使用 报错

最近使用 pod init 报错

ERROR:  SSL verification error at depth 0: certificate has expired (10)
ERROR:  Certificate /C=CN/ST=ZheJiang/L=HangZhou/O=Alibaba (China) Technology Co., Ltd./CN=*.taobao.org expired at 2018-12-05T03:16:02Z
ERROR:  SSL verification error at depth 0: certificate has expired (10)
ERROR:  Certificate /C=CN/ST=ZheJiang/L=HangZhou/O=Alibaba (China) Technology Co., Ltd./CN=*.taobao.org expired at 2018-12-05T03:16:02Z
ERROR:  SSL verification error at depth 0: certificate has expired (10)
ERROR:  Certificate /C=CN/ST=ZheJiang/L=HangZhou/O=Alibaba (China) Technology Co., Ltd./CN=*.taobao.org expired at 2018-12-05T03:16:02Z
ERROR:  Could not find a valid gem 'cocoapods' (>= 0), here is why:
          Unable to download data from https://ruby.taobao.org/ - SSL_connect returned=1 errno=0 state=error: certificate verify failed (https://ruby.taobao.org/specs.4.8.gz)
ERROR:  SSL verification error at depth 0: certificate has expired (10)
ERROR:  Certificate /C=CN/ST=ZheJiang/L=HangZhou/O=Alibaba (China) Technology Co., Ltd./CN=*.taobao.org expired at 2018-12-05T03:16:02Z

是由于淘宝的tuby源不能用了
我们先删除原来的ruby源然后更新为
gem sources -a https://gems.ruby-china.com/
重新pod init 即可