Forcing https in elasticbeanstalk with certificate from ACM

Question

I have provisioned a scalable EB(Elasticbeanstalk) rails(puma) instance. I have applied for https through ACM(Amazon Certificate Manager) and applied it to my load balancer.

Answer 1

The current AWS EB Rails and Node.js setups both use nginx (if your web server is apache see this answer), so the following should work (adapted from this question):

Create the file .ebextensions/01-force-https.config (the .config is important, not .conf) with the following content.

If your environment is a single instance:

files:
  "/etc/nginx/conf.d/01-force-https.conf":
    owner: root
    group: root
    mode: "000644"
    content: |
      server {
          listen 8080;
          return 301 https://$host$request_uri;
      }

If your environment is load balanced, you unfortunately cannot simply add to the existing config but need to modify it with sed:

files:
  "/tmp/45_nginx_https_rw.sh":
    owner: root
    group: root
    mode: "000644"
    content: |
      #! /bin/bash

      CONFIGURED=`grep -c "return 301 https" /opt/elasticbeanstalk/support/conf/webapp_healthd.conf`

      if [ $CONFIGURED = 0 ]
        then
          sed -i '/listen 80;/a \    if ($http_x_forwarded_proto = "http") { return 301 https://$host$request_uri; }\n' /opt/elasticbeanstalk/support/conf/webapp_healthd.conf
          logger -t nginx_rw "https rewrite rules added"
          exit 0
        else
          logger -t nginx_rw "https rewrite rules already set"
          exit 0
      fi

container_commands:
  00_appdeploy_rewrite_hook:
    command: cp -v /tmp/45_nginx_https_rw.sh /opt/elasticbeanstalk/hooks/appdeploy/enact
  01_configdeploy_rewrite_hook:
    command: cp -v /tmp/45_nginx_https_rw.sh /opt/elasticbeanstalk/hooks/configdeploy/enact
  02_rewrite_hook_perms:
    command: chmod 755 /opt/elasticbeanstalk/hooks/appdeploy/enact/45_nginx_https_rw.sh /opt/elasticbeanstalk/hooks/configdeploy/enact/45_nginx_https_rw.sh
  03_rewrite_hook_ownership:
    command: chown root:users /opt/elasticbeanstalk/hooks/appdeploy/enact/45_nginx_https_rw.sh /opt/elasticbeanstalk/hooks/configdeploy/enact/45_nginx_https_rw.sh

Then add it to your git repo or app bundle and eb deploy. This creates /etc/nginx/conf.d/01-force-https.conf which is automatically included from /etc/nginx/nginx.conf. Note that eb deploy won't delete the file on the server if you later remove the corresponding file from .ebextensions. Also, I found the following helpful in debugging through eb ssh:

sudo service nginx configtest
sudo service nginx restart