cleanse-go-mods

#!/usr/bin/env python3
# Steve Willoughby <nr-swilloughby@newrelic.com>
#
cur_agent_version='3.29.0'
minimum_go_version='1.19'
import os
import os.path
import re

for root, dirs, files in os.walk('.'):
    for f in files:
        if f == 'go.mod':
            target = os.path.join(root, f)
            os.rename(target, target+'.bak')
            with open(target+'.bak') as src:
                with open(target, 'w') as dst:
                    block = hold = False
                    replace_line = False
                    for line in src:
                        if not line.strip():
                            dst.write('\n')
                            continue

                        if line.strip() == 'require (':
                            hold=True
                            block=True
                            continue

                        if line.strip() == ')':
                            if block and hold:
                                block = hold = False
                                continue
                            block = hold = False

                        if '// indirect' in line:
                            continue

                        if block:
                            if hold:
                                dst.write('require (\n')
                                hold = False

                        if re.search(r'^.*go\s+\d+\.\d+', line):
                            dst.write(f'go {minimum_go_version}\n')
                            continue

                        if re.search(r'newrelic/go-agent/v3\s+v(\d+\.\d+\.\d+)', line):
                            line = re.sub(r'newrelic/go-agent/v3\s+v(\d+\.\d+\.\d+)', 
                                       f'newrelic/go-agent/v3 v{cur_agent_version}',
                                       line)
                            replace_line = True

                        if re.search(r'replace\s+github.com/newrelic/go-agent/v3\s+', line):
                            continue

                        dst.write(line)

                    if replace_line:
                        my_path = target
                        back_list = []
                        while my_path:
                            my_path, this = os.path.split(my_path)
                            if this == 'integrations' or this == '.':
                                break
                            back_list.append('..')
                        else:
                            back_list = None    # something went wrong, don't add the line

                        if back_list:
                            dst.write('replace github.com/newrelic/go-agent/v3 => ' +
                                      os.path.join(*back_list) + '\n')