Very basic SQL Formatter

sql-fmt.py

#!/usr/bin/env python3

## Simple, regex-based SQL formatter. The core idea is to not muck around
## with any indenting, but to simply convert keywords to uppercase. What an
## utterly annoying convention today.

## Reads stdin, writes to stdout, allowing for use in IDE processes or similar.

import sys
import re

## Incomplete set, updated on demand. :-)
keywords = [
    'all',
    'and',
    'as',
    'char',
    'create',
    'double precision',
    'from',
    'function',
    'inner',
    'int',
    'join',
    'language',
    'on',
    'or',
    'replace',
    'returns',
    'select',
    'sql',
    'table',
    'text',
    'union',   
    'where',
]

# Potential issues with encoding -- relying on platform defaults.
val = sys.stdin.read()

for k in keywords:
    val = re.sub(
        # Ignore comment-only lines, limitation: inline comments affected still
        r'^(?!\s*--)(.*)' + k + r'(\s+|\[|\(|,)',
        r'\1' + k.upper() + r'\2',
        val,
        flags=re.IGNORECASE | re.MULTILINE
    )

print(val, end='')