Default Log4j properties in Native Kubernetes

[Vladislav Keda]

Hi all!

Is it possible to change Flink* log4j-console.properties* in Native
Kubernetes (for example in Kubernetes Application mode) without rebuilding
the application docker image?

I was trying to inject a .sh script call (in the attachment) before
/docker-entrypoint.sh, but this workaround did not work (k8s gives me an
exception that the log4j* files are write-locked because there is a
configmap over them).

Is there another way to change log4j* files?

Thank you very much in advance!

Best Regards,
Vladislav Keda

#!/usr/bin/env bash

# shellcheck disable=SC2034
LOG4J_CLI_PROPERTIES_PATH="${FLINK_HOME}/conf/log4j-cli.properties"
# shellcheck disable=SC2034
LOG4J_CONSOLE_PROPERTIES_PATH="${FLINK_HOME}/conf/log4j-console.properties"
# shellcheck disable=SC2034
LOG4J_SESSION_PROPERTIES_PATH="${FLINK_HOME}/conf/log4j-session.properties"
# shellcheck disable=SC2034
LOG4J_PROPERTIES_PATH="${FLINK_HOME}/conf/log4j.properties"

override_properties() {
  local properties_var=$1
  local properties_path_var="${properties_var}_PATH"

  local content="${!properties_var}"
  local path="${!properties_path_var}"

  if [ -n "${content}" ]; then
    echo "$0: ${properties_var} env variable is set. Overwriting ${path}"
    echo "${content}" > "${path}"
  else
    echo "$0: ${properties_var} env variable is not set. Using Flink's ${path}"
  fi
}

override_properties "LOG4J_CLI_PROPERTIES"
override_properties "LOG4J_CONSOLE_PROPERTIES"
override_properties "LOG4J_SESSION_PROPERTIES"
override_properties "LOG4J_PROPERTIES"