Shortcut for switch environments in IaC repositories

switch.py

import sys
import os
import pathlib

PREFIX = os.getenv("CE_PREFIX", "environments/")


def main():
    """ Find the next environment path to switch to in the current IaC project.
        Example:
            current directory: dev/infrastructure/container
            result:   ../../../prod/infrastructure/container

        To be used in conjunction with this alias:
        alias ce="python3 ~/switch.py && cd \$(python3 ~/switch.py)"

        Usage: ce
    """
    cwd = str(pathlib.Path.cwd())
    envs = []
    env = ""

    # try to identify the environments level
    if PREFIX not in cwd:
        print(f"Prefix {PREFIX} not in cwd {cwd}. Dont know what to do. " +
              "Hint: Overwrite with valid prefix by setting the environment variable CE_PREFIX.")
        sys.exit(1)

    # find the env base directory based on the prefix and collect all available environments
    env_base_dir = cwd[:cwd.find(PREFIX) + len(PREFIX)]
    for entity in pathlib.Path(env_base_dir).glob("*"):
        if entity.is_dir():
            envs.append(entity.name)

    # split up cwd into useful components
    sub_path = cwd.split(PREFIX)[1]
    current_env = "".join(sub_path.split("/")[0])
    sub_path_without_env = "/".join(sub_path.split("/")[1:])

    # find next possible environment to switch to
    found_next = False
    i = 1
    while not found_next and i < len(envs):
        env = envs[(envs.index(current_env) + i) % len(envs)]
        new_sub_path = pathlib.Path(env + "/" + sub_path_without_env)
        new_path = pathlib.Path(env_base_dir + "/" + str(new_sub_path))
        if new_path.exists():
            found_next = True
        i += 1

    if not found_next:
        print(f"Cloudnt find the same sub path {sub_path} in one of the other available environments: {envs}. "
              "Dont know what to do.")
        sys.exit(1)

    # construct ../../ to get from current path to env_base_dir
    dots = "".join(["../" for _ in str(new_sub_path).split("/")])

    print(f"{dots + str(new_sub_path)}")


main()