I already use env inject plugin. 
[EnvInject] - Loading node environment variables.
Building in workspace /var/lib/jenkins/jobs/test_pyenv/workspace
[EnvInject] - Executing scripts and injecting environment variables after the SCM step.
[EnvInject] - Injecting as environment variables the properties content
HTTPS_PROXY=pkg.proxy.prod.jp.local:10080
HTTP_PROXY=pkg.proxy.prod.jp.local:10080

[EnvInject] - Variables injected successfully.
$ bash -c "[ -d \$HOME/.pyenv ]"
Installing pyenv...
$ bash -c "git clone
https://github.com/yyuu/pyenv.git
\$HOME/.pyenv && cd \$HOME/.pyenv && git checkout master"
Initialized empty Git repository in /home/jenkins/.pyenv/.git/
error: Failed connect to github.com:443; Operation now in progress while accessing
https://github.com/yyuu/pyenv.git/info/refs
fatal: HTTP request failed
FATAL: (CommandError) failed: "git clone
https://github.com/yyuu/pyenv.git
$HOME/.pyenv && cd
$HOME/.pyenv && git checkout master"
org.jruby.exceptions.RaiseException: (CommandError) failed: "git clone
https://github.com/yyuu/pyenv.git
$HOME/.pyenv && cd
$HOME/.pyenv && git checkout master"
at RUBY.run(/var/lib/jenkins/plugins/pyenv/WEB-INF/classes/lib/pyenv/invoke.rb:18)
at RUBY.install!(/var/lib/jenkins/plugins/pyenv/WEB-INF/classes/lib/pyenv.rb:47)
at RUBY.setup!(/var/lib/jenkins/plugins/pyenv/WEB-INF/classes/lib/pyenv.rb:20)
at RUBY.setup(/var/lib/jenkins/plugins/pyenv/WEB-INF/classes/models/pyenv_wrapper.rb:57)
at RUBY.setUp(/var/lib/jenkins/plugins/pyenv/WEB-INF/classes/vendor/gems/gems/jenkins-plugin-runtime-0.2.3/lib/jenkins/model/environment_proxy.rb:8)
Finished: FAILURE