csv-converter 0.0.3

Tool to convert CSV files based on JSON config.

A simple tool that uses a JSON config file (or a config dict) to convert one CSV to another.

Simplest use case is to just list the new headers and link them to the old headers, like so:

{
"New Column Header One": "Old Column Header One",
"New Column Header Two": "Old Column Header Two"
}

A slightly more useful version specifies a default to use (implemented using the "or" operator value_from_old_column or default):

{
  "New Header One": {
    "old_column": "Old Header One",
    "default": "DEFAULT VALUE FOR ONE"
  },
  "New Header Two": {
    "old_column": "Old Header Two",
    "default": "DEFAULT VALUE FOR TWO"
  }
}

The third and final currently implemented option is to use a lambda function (use of full functions is planned):

{
  "New Header One": {
    "old_column": "Old Header One",
    "default": "DEFAULT FOR ONE",
    "lambda": "lambda a, b: str(a.get(b.get('old_column'))).lower()"
  },
  "New Header Two": {
    "old_column": "Old Header Two",
    "default": "DEFAULT FOR TWO",
    "lambda": "lambda a, b: str(a.get(b.get('old_column'))).lower()"
  }
}

It will run the lambda as:

item['lambda'] = "lambda a, b: str(a.get(b.get('old_column'))).lower()"
exec(f"c = {item.get('lambda')}", globals())
return c(line, item)

Where line is the current line of the source CSV, and item is the current element from the JSON file (the current column).

Usage:

from csv_converter import CSVConverter
converter = CSVConverter(config_file_name='path-to-config.json')
output = converter.convert(input_file_name='path-to-source.csv')