Terraform Deployment Helper

tfdh.py

import argparse
import os
import subprocess
import sys

# Python 2 and Python 3 compatability
try:
    subprocess_run = subprocess.run

except AttributeError:
    def run(*popenargs, **kwargs):
        input = kwargs.pop("input", None)
        check = kwargs.pop("handle", False)

        if input is not None:
            if 'stdin' in kwargs:
                raise ValueError('stdin and input arguments may not both be used.')
            kwargs['stdin'] = subprocess.PIPE

        process = subprocess.Popen(*popenargs, **kwargs)
        try:
            stdout, stderr = process.communicate(input)
        except:
            process.kill()
            process.wait()
            raise
        retcode = process.poll()
        if check and retcode:
            raise subprocess.CalledProcessError(
                retcode, process.args, output=stdout, stderr=stderr)

        # Make sure the API is the same
        # with Python 2 and 3
        ret_obj = lambda: ()
        setattr(ret_obj, 'stderr', stderr)
        setattr(ret_obj, 'stdout', stdout)
        setattr(ret_obj, 'returncode', retcode)

        return ret_obj

    subprocess_run = run


if __name__ == '__main__':
    parser = argparse.ArgumentParser(
        description='Terraform-Development Deployment Helper for OmiseGO.'
    )
    parser.add_argument(
        '-f', '--template-dir', required=True,
        help='Reference dir with an existing configuration template'
    )
    parser.add_argument(
        '-p', '--prefix', required=True,
        help='Prefixes: [dev|prod|audit]'
    )
    parser.add_argument(
        '-t', '--tag', required=True,
        help='Plasma contract SHA (only first 7 characters)'
    )
    parser.add_argument(
        '-n', '--network', required=True,
        help='Ethereum network'
    )
    parser.add_argument(
        '-N', '--number', required=True,
        help='Deployment number'
    )

    args = parser.parse_args()

    # Pad our number
    new_number = args.number.rjust(2, '0')

    # Gets root directory (of where script is executed)
    cwd = os.getcwd()

    old_template_dir = args.template_dir.split('/')[0]
    old_prefix = old_template_dir.split('-')[0]
    old_tag = old_template_dir.split('-')[1]
    old_network = old_template_dir.split('-')[2]
    old_number = old_template_dir.split('-')[3].replace('/', '')

    new_dir_name = args.prefix + '-' \
        + args.tag + '-' \
        + args.network + '-' \
        + new_number

    new_dir_cwd = os.path.join(cwd, new_dir_name)

    # Copy over existing dir to new dir
    cp_result = subprocess_run(
        ['cp', '-r', args.template_dir, new_dir_name],
        cwd=cwd
    )

    if cp_result.returncode != 0:
        sys.exit(1)

    # Edit backend.tf
    with open(os.path.join(new_dir_cwd, 'backend.tf'), 'r') as f:
        backend_tf_content = f.readlines()

    backend_tf_content = list(map(
        lambda x: x.replace(old_template_dir, new_dir_name),
        backend_tf_content
    ))

    with open(os.path.join(new_dir_cwd, 'backend.tf'), 'w') as f:
        f.writelines(backend_tf_content)

    # Edit terraform.tfvars
    with open(os.path.join(new_dir_cwd, 'terraform.tfvars'), 'r') as f:
        tf_vars_content = f.readlines()

    def modify_tf_vars_content(s):
        # Don't wanna modify project id at this stage
        if 'omisego-development' in s:
            return s

        s = s.replace(old_prefix, args.prefix)
        s = s.replace(old_tag, args.tag)
        s = s.replace(old_network, args.network)
        s = s.replace(old_number, new_number)

        return s

    tf_vars_content = list(map(
        modify_tf_vars_content,
        tf_vars_content
    ))

    with open(os.path.join(new_dir_cwd, 'terraform.tfvars'), 'w') as f:
        f.writelines(tf_vars_content)

    print('Using directory ' + old_template_dir + ' as base template')
    print('Created new directory: ' + new_dir_name)
    print('Configuration files written ' + new_dir_name)