User FAQ

Use of environment variables on the command line

As discussed in Docker's documentation, the container's command is not necessarily executed in a shell, in which case environment variables are not expanded in command-line arguments. In particular, non-default commands are specified via Kubernetes's API using the array form of Docker's Cmd argument, which causes the command to be execed directly. You can cause environment variables to be evaluated by simply making your command a shell, with your application's command line as its argument. For example:

{ "command": [ "sh", "-c", "redis-server /etc/redis/redis.conf --slaveof $SERVICE_HOST $REDIS_MASTER_SERVICE_PORT"] }