unwrap_e2e_log.py

#!/usr/bin/env python3

# this script takes `expectrl` log outputs, such as the ones emitted by
# e2e tests, and unwraps them into a more readable format

import re
import sys

UNICODE = re.compile(r'\\u{([\da-fA-F]+)}')

def main():
    if len(sys.argv) > 1:
        with open(sys.argv[1], 'r') as f:
            process_file(f)
    else:
        process_file(sys.stdin)

def process_file(f):
    for line in f.readlines():
        process_line(line)
    sys.stdout.flush()

def process_line(line):
    for m in UNICODE.findall(line):
        line = line.replace(f'\\u{{{m}}}', f'\\u{int(m, 16):04x}')
    line = \
        try_parse_line_str(line) or \
        try_parse_line_bytes(line) or \
        ''
    sys.stdout.write(line)

def try_parse_line_str(line):
    prefix_full = 'read: "'
    prefix = prefix_full[:-1]
    if line.startswith(prefix_full):
        return eval(line[len(prefix):])

def try_parse_line_bytes(line):
    prefix = 'read:(bytes): '
    if line.startswith(prefix):
        return bytes(eval(line[len(prefix):])).decode("utf-8", "backslashreplace")

if __name__ == '__main__':
    main()