Adds jenkins_protocol_https

When set to 'true' (default value), configures nginx with proxy_redirect from http: to https:

When set to 'false', the proxy allows http: requests without redirecting to https:.

Ref https://github.com/edx/edx-analytics-configuration/blob/master/roles/jenkins/templates/etc/nginx/sites-available/jenkins.j2#L8-L11

playbooks/roles/jenkins_master/defaults/main.yml

@@ -4,6 +4,7 @@ jenkins_group: "edx"
 jenkins_server_name: "jenkins.testeng.edx.org"
 jenkins_port: 8080
 jenkins_nginx_port: 80
+jenkins_protocol_https: true
 
 jenkins_version: "1.638"
 jenkins_deb_url: "http://pkg.jenkins-ci.org/debian/binary/jenkins_{{ jenkins_version }}_all.deb"

playbooks/roles/jenkins_master/templates/etc/nginx/sites-available/jenkins.j2

@@ -5,8 +5,10 @@ server {
   location / {
     proxy_pass              http://localhost:{{ jenkins_port }};
 
+    {% if jenkins_protocol_https %}
     # Rewrite HTTPS requests from WAN to HTTP requests on LAN
     proxy_redirect http:// https://;
+    {% endif %}
 
     # The following settings from https://wiki.jenkins-ci.org/display/JENKINS/Running+Hudson+behind+Nginx
     sendfile off;