Configuration Files

Inspired by Evan “Hippy” Slatis work

1. Config file format and loading rules

Configuration files loading is following these rules or best practices:

• all env files are now loaded as properties file, it means bash arrays cannot be declared Eg: arrays should be converted to a string list separated by colon, and has to converted when needed.
• All .env files have the ability to override value by env variable
• all variables have to be written on one line, it is not possible to cut lines over multiple line
• First variable set takes precedence, so writing following file would result to VAR1=value1

VAR1=value1
VAR1=value2

2. Config file overloading values

• Best practice is to override variables only by
  • command argument –bash-framework-config to allow loading alternate env before other default files
  • command argument (–verbose, …) allows to override default displayed log level
  • in env files, always allow value to be overridden by prioritized variables
    • using bash variable default value mechanism, in following example, BASH_FRAMEWORK_LOG_LEVEL will be equal to 0 only if it hasn’t been set previously

BASH_FRAMEWORK_LOG_LEVEL="${BASH_FRAMEWORK_LOG_LEVEL:-0}"

• Provide –config argument to see resulting config file + information about order of loaded config files for debugging purpose.

• It is also possible to use environment variable, but highly discouraged to generalize this practice as it could lead to unwanted results if variables are not well scoped.

3. Config files loading order

The framework function Env::requireLoad loads the following files in this order if they are existing and are readable:

• files provided in BASH_FRAMEWORK_ENV_FILES env variable array
• ${FRAMEWORK_ROOT_DIR}/.framework-config if exists
• .framework-config from current directory if exists
• file from option –bash-framework-config

Options can override values provided by these env files:

• if –verbose or -v argument is passed, set BASH_FRAMEWORK_DISPLAY_LEVEL to 3 (INFO)
• if -vv argument is passed, set BASH_FRAMEWORK_DISPLAY_LEVEL to 4 (DEBUG)
• later on, will manage other kind of arguments
• additional files provided by this bash array variable, see below.
• framework default values file, see below.

Eg: additional environment files

BASH_FRAMEWORK_ENV_FILES=("${HOME}/.bash-tools/.env" "${HOME}/.env")

Eg: framework default values file

BASH_FRAMEWORK_LOG_LEVEL="${BASH_FRAMEWORK_LOG_LEVEL:-0}"
BASH_FRAMEWORK_DISPLAY_LEVEL="${BASH_FRAMEWORK_DISPLAY_LEVEL:-${__LEVEL_WARNING}}"
BASH_FRAMEWORK_LOG_FILE="${BASH_FRAMEWORK_LOG_FILE:-"${FRAMEWORK_ROOT_DIR}/logs/${SCRIPT_NAME}.log"}"
BASH_FRAMEWORK_LOG_FILE_MAX_ROTATION="${BASH_FRAMEWORK_LOG_FILE_MAX_ROTATION:-5}"

Activity diagram to explain how Env::requireLoad is working:

activity diagram source code.