Set SESSION_COOKIE_SECURE for deployed environments.

This sets the "Secure" attribute on cookies sent to the client:

https://flask.palletsprojects.com/en/1.1.x/config/#SESSION_COOKIE_SECURE

README.md

@@ -257,6 +257,7 @@ To generate coverage reports for the Javascript tests:
 - `SESSION_COOKIE_DOMAIN`: String value specifying the name to use for the session cookie. This should be set to the root domain so that it is valid for both the main site and the authentication subdomain. https://flask.palletsprojects.com/en/1.1.x/config/#SESSION_COOKIE_DOMAIN
 - `SESSION_KEY_PREFIX`: A prefix that is added before all session keys: https://pythonhosted.org/Flask-Session/#configuration
 - `SESSION_TYPE`: String value specifying the cookie storage backend. https://pythonhosted.org/Flask-Session/
+- `SESSION_COOKIE_SECURE`: https://flask.palletsprojects.com/en/1.1.x/config/#SESSION_COOKIE_SECURE
 - `SESSION_USE_SIGNER`: Boolean value specifying if the cookie sid should be signed.
 - `SQLALCHEMY_ECHO`: Boolean value specifying if SQLAlchemy should log queries to stdout.
 - `STATIC_URL`: URL specifying where static assets are hosted.

config/base.ini

@@ -43,6 +43,7 @@ SERVER_NAME
 SESSION_COOKIE_NAME=atat
 SESSION_COOKIE_DOMAIN
 SESSION_KEY_PREFIX=session:
+SESSION_COOKIE_SECURE=false
 SESSION_TYPE = redis
 SESSION_USE_SIGNER = True
 SQLALCHEMY_ECHO = False

deploy/azure/atst-envvars-configmap.yml

@@ -32,6 +32,7 @@ data:
   REDIS_HOST: atat.redis.cache.windows.net:6380
   REDIS_TLS: "true"
   SESSION_COOKIE_DOMAIN: atat.code.mil
+  SESSION_COOKIE_SECURE: "true"
   STATIC_URL: https://atat-cdn.azureedge.net/static/
   TZ: UTC
   UWSGI_CONFIG_FULLPATH: /opt/atat/atst/uwsgi.ini