configuration parameters management using environment variables

[delfer]

Based on https://github.com/delfer/docker-alpine-ftp-server/pull/45 and improved by claude sonnet 3.7

Key Improvements: More Efficient Processing:

Updates the file only once instead of for each parameter Collects new parameters and adds them all at once Better Error Handling:

Checks if files exist and are writable Validates critical operations like file copying Provides meaningful error messages Improved Pattern Matching:

Handles various formatting styles in the config file Properly matches parameters regardless of whitespace Safer File Operations:

Uses temporary files for all operations Ensures proper cleanup even if errors occur This improved script should work reliably in all the scenarios you described and is much more robust against potential issues.

[damwiw]

Hi, I checked the Claude reviewed code. Looks fine, even if I didn't test it. Some parts could be simplified for the NEW_PARAMS_FILE: Instead of:

+    # Add to the list of new parameters
+    echo "${param_name}|${value}" >> "${NEW_PARAMS_FILE}"

I would do:

    # Add to the list of new parameters
    echo "${param_name}=${value}" >> "${NEW_PARAMS_FILE}"

Then I would replace:

+if [ -s "${NEW_PARAMS_FILE}" ]; then
+  echo "" >> "${TEMP_FILE}"
+  echo "# Parameters added by environment variables" >> "${TEMP_FILE}"
+
+  while IFS="|" read param_name value; do
+    echo "${param_name}=${value}" >> "${TEMP_FILE}"
+  done < "${NEW_PARAMS_FILE}"
+fi
+
+# Replace the original file with the updated one
+cat "${TEMP_FILE}" > "${CONF_FILE_PATH}"

by:

if [ -s "${NEW_PARAMS_FILE}" ]; then
  echo "" >> "${TEMP_FILE}"
  echo "# Parameters added by environment variables" >> "${TEMP_FILE}"

  cat "${NEW_PARAMS_FILE}" >> "${TEMP_FILE}"
fi

# Replace the original file with the updated one
mv -f "${TEMP_FILE}" "${CONF_FILE_PATH}"