APPLICATION_ENVIRONMENT: New configuration variable

Add a new application configuration variable,
"APPLICATION_ENVIRONMENT" that will be useful to distinguish resources
for different instances of the application that might run on the same
host. The default value is an empty string in order to allow backwards
compatibility with existing code.

An example of where this finds utility: If you run multiple instances
of the application, but they all share the same redis instance, then
key-collisions from the different running applications will happen,
leading to subtle, difficult to troubleshoot bugs.

1 files changed, 7 insertions, 0 deletions

diff --git a/gn3/settings.py b/gn3/settings.py
index e988106..028f083 100644
--- a/gn3/settings.py
+++ b/gn3/settings.py
@@ -7,6 +7,13 @@ application settings.
 import os
 import tempfile
 
+### APPLICATION_ENVIRONMENT: can be something like
+### production, staging, development, tux02-prod, tux04-staging, etc.
+### Useful to distinguish resources for different containers if you run multiple
+## containers on the same host e.g. distinguish keys on a redis instance for
+## different containers.
+APPLICATION_ENVIRONMENT = ""
+
 DATA_DIR = ""
 GEMMA_WRAPPER_CMD = os.environ.get("GEMMA_WRAPPER", "gemma-wrapper")
 CACHEDIR = ""