Allow ecommerce gunicorn workers to be regularly restarted

Leverages gunicorn's max-requests option to restart workers after they've processed a configured number of requests. Also adds this option to cookiecutter role. ECOM-5448.

playbooks/roles/ansible-role-django-ida/templates/defaults/main.yml.j2

@@ -93,6 +93,7 @@
 {{ role_name|upper }}_GUNICORN_EXTRA: ""
 {{ role_name|upper }}_GUNICORN_EXTRA_CONF: ""
 {{ role_name|upper }}_GUNICORN_WORKER_CLASS: "gevent"
+{{ role_name|upper }}_GUNICORN_MAX_REQUESTS: !!null
 
 {{ role_name|upper }}_HOSTNAME: '~^((stage|prod)-)?{{ role_name|replace('_', '-') }}.*'
 

playbooks/roles/ansible-role-django-ida/templates/templates/edx/app/ROLE_NAME/ROLE_NAME_gunicorn.py.j2

@@ -9,4 +9,8 @@ pythonpath = "{{ '{{' }} {{ role_name }}_code_dir }}"
 workers = {{ '{{' }} {{ role_name|upper }}_GUNICORN_WORKERS }}
 worker_class = "{{ '{{' }} {{ role_name|upper }}_GUNICORN_WORKER_CLASS }}"
 
+{{ '{%' }} if {{ role_name|upper }}_GUNICORN_MAX_REQUESTS {{ '%}' }}
+max_requests = {{ '{{' }} {{ role_name|upper }}_GUNICORN_MAX_REQUESTS }}
+{{ '{%' }} endif {{ '%}' }}
+
 {{ '{{' }} {{ role_name|upper }}_GUNICORN_EXTRA_CONF }}

playbooks/roles/ecommerce/defaults/main.yml

@@ -198,6 +198,7 @@ ECOMMERCE_GUNICORN_WORKERS: "2"
 ECOMMERCE_GUNICORN_EXTRA: ""
 ECOMMERCE_GUNICORN_EXTRA_CONF: ""
 ECOMMERCE_GUNICORN_WORKER_CLASS: "gevent"
+ECOMMERCE_GUNICORN_MAX_REQUESTS: !!null
 
 #
 # vars are namespace with the module name.

playbooks/roles/ecommerce/templates/edx/app/ecommerce/ecommerce_gunicorn.py.j2

@@ -9,4 +9,8 @@ pythonpath = "{{ ecommerce_code_dir }}"
 workers = {{ ECOMMERCE_GUNICORN_WORKERS }}
 worker_class = "{{ ECOMMERCE_GUNICORN_WORKER_CLASS }}"
 
+{% if ECOMMERCE_GUNICORN_MAX_REQUESTS %}
+max_requests = {{ ECOMMERCE_GUNICORN_MAX_REQUESTS }}
+{% endif %}
+
 {{ ECOMMERCE_GUNICORN_EXTRA_CONF }}