bootloader.py

import logging
import asyncio
import pathlib
import argparse
import copy
import sys
import os
import re
import shutil
import base64
import zipfile
from pathlib import Path

import aiodocker
import aiohttp
import yaml
import yaml.scanner
from tenacity import retry, stop_after_attempt, wait_exponential

from common.config import config, static
from common.docker_helpers import (create_secret, get_secret, delete_secret, get_network, connect_to_aiodocker,
                                   docker_context, stream_docker_log, logger as docker_logger, disconnect_from_network,
                                   update_service, get_replicas)

logging.basicConfig(level=logging.DEBUG, format="{asctime} - {name} - {levelname}:{message}", style='{')

logger = logging.getLogger("BOOTLOADER")
static.set_local_hostname("local_bootloader")

COMPOSE_BASE = {
    "version": "3.5",
    "services": {},
    "networks": {"walkoff_network": {"external": True}},
    "secrets": {"encryption_key": {"external": True}}
}

APP_NAME_PREFIX = "walkoff_"

p = Path('./apps').glob('**/*')

volume_names = (static.REGISTRY_VOLUME, static.MINIO_VOLUME, static.MONGO_VOLUME, static.PORTAINER_VOLUME)
key_names = (static.ENCRYPTION_KEY, static.INTERNAL_KEY, static.MONGO_KEY, static.REDIS_KEY,
             static.MINIO_ACCESS_KEY, static.MINIO_SECRET_KEY)


def parse_yaml(path):
    with open(path) as fp:
        try:
            return yaml.safe_load(fp)
        except yaml.YAMLError as e:
            logger.info(f"Invalid yaml: {path}. {e}")
        except yaml.scanner.ScannerError as e:
            logger.info(f"Invalid yaml: {path}. {e}")


def dump_yaml(path, obj):
    with open(path, 'w') as fp:
        try:
            return yaml.dump(obj, fp)
        except yaml.YAMLError as e:
            logger.info(f"Invalid yaml: {path}. {e}")


def parse_env_file(path):
    with open(path) as fp:
        return [line.strip() for line in fp]


def compose_from_app(path: pathlib.Path, name):
    env_txt = path / "env.txt"
    env_file = {}
    if env_txt.exists():
        env_file = {"environment": parse_env_file(env_txt)}
    compose = copy.deepcopy(COMPOSE_BASE)
    build = {"build": {"context": str(path), "dockerfile": "Dockerfile"}}
    image = {"image": f"{config.DOCKER_REGISTRY}/{APP_NAME_PREFIX}{name}:{path.name}"}
    networks = {"networks": ["walkoff_network"]}
    deploy = {"deploy": {"mode": "replicated", "replicas": 0, "restart_policy": {"condition": "none"}}}
    config_mount = {"configs": ["common_env.yml"]}
    secret_mount = {"secrets": ["walkoff_encryption_key", "walkoff_redis_key"]}
    shared_path = os.getcwd() + "/data/shared"
    final_mount = shared_path + ":/app/shared"
    volumes_mount = {"volumes": [final_mount]}
    compose["services"] = {name: {**build, **image, **networks, **deploy, **config_mount,
                                  **secret_mount, **volumes_mount, **env_file}}
    return compose


async def log_proc_output(proc, silent=False):
    stdout, stderr = await proc.communicate()
    if not silent:
        if proc.returncode:
            for line in stderr.decode().split('\n'):
                if line != '':
                    logger.error(line)
        else:
            for line in stdout.decode().split('\n'):
                if line != '':
                    logger.info(line)


def merge_composes(base, others):
    if not isinstance(base, dict):
        base = parse_yaml(base)
        if base.get("services") is None:
            base["services"] = {}
    if not isinstance(others[0], dict):
        others = [parse_yaml(o) for o in others]
    for o in others:
        base["services"].update(o.get("services", {}))
    return base


def generate_app_composes():
    # TODO: Probably find a way to incorporate the app repo in here as well to eliminate mounting files to umpire
    composes = []
    for app in pathlib.Path(config.APPS_PATH).iterdir():
        if not app.is_dir():
            try:
                zip_ref = zipfile.ZipFile(app, 'r')
                zip_ref.extractall(config.APPS_PATH)
                zip_ref.close()
                os.remove(app)
            except Exception as e:
                logger.error(f"Zip error: {e}")
                continue

    for app in pathlib.Path(config.APPS_PATH).iterdir():
        #  grabs only directories and ignores all __* directories i.e. __pycache__

        if app.is_dir() and not re.fullmatch(r"(__.*)", app.name):
            for version in app.iterdir():
                # grabs all valid version directories of form "v0.12.3.45..."
                if re.fullmatch(r"((\d\.?)+)", version.name):
                    composes.append(compose_from_app(version, f"app_{app.name}"))
                logger.info(f"Generated compose for {app.name} version: {version.name}")
    return composes


async def are_you_sure(prompt):
    try:
        resp = input(f"{prompt}\n\nAre you sure? (yes/no): ")
        while resp.lower() not in ("yes", "no"):
            resp = input("Please answer 'yes' or 'no': ")
    except KeyboardInterrupt:
        return False

    if resp.lower() == "yes":
        return True
    else:
        return False


async def create_encryption_key(docker_client, key_name, value=None):
    try:
        await get_secret(docker_client, key_name)
    except aiodocker.exceptions.DockerError:
        logger.info(f"Creating secret {key_name}...")
        try:
            key = value if value else base64.urlsafe_b64encode(os.urandom(32))
            await create_secret(docker_client, key_name, key)
            return key
        except aiodocker.exceptions.DockerError as e:
            logger.exception(f"Could not create Docker Secret {key_name}, exiting. Reason: {e}")
            os._exit(1)
    else:
        logger.info(f"Skipping secret {key_name} creation, it already exists.")
        return "Key already existed."


async def delete_encryption_key(docker_client, key_name):
    try:
        await delete_secret(docker_client, key_name)
        logger.info(f"Deleted secret {key_name}...")
    except aiodocker.exceptions.DockerError:
        logger.info(f"Skipping secret {key_name} deletion, it doesn't exist.")


async def check_for_network(docker_client):
    try:
        await get_network(docker_client, "walkoff_network")
        return True
    except aiodocker.exceptions.DockerError:
        return False


# async def delete_dir_contents(path):
#     logger.info(f"Deleting directory contents of {path}...")
#     try:
#         for root, dirs, files in os.walk(path):
#             for f in files:
#                 os.unlink(os.path.join(root, f))
#             for d in dirs:
#                 shutil.rmtree(os.path.join(root, d))
#     except Exception as e:
#         logger.exception(f"Could not remove contents in {path}. Reason: {e}")


@retry(stop=stop_after_attempt(10), wait=wait_exponential(min=1, max=10))
async def delete_volume(docker_client, volume_name):
    try:
        vol = aiodocker.docker.DockerVolume(docker_client, volume_name)
        await vol.delete()
        logger.info(f"Deleted volume {volume_name}.")
    except aiodocker.exceptions.DockerError as e:
        if e.status == 404:
            logger.info(f"Skipping removal of {volume_name}, it doesn't exist.")
        else:
            logger.info(f"Failed to remove volume {volume_name}, a container may still be using it. "
                        f"Waiting to try again...")
            raise e


@retry(stop=stop_after_attempt(10), wait=wait_exponential(min=1, max=10))
async def deploy_compose(compose):
    try:
        if not isinstance(compose, dict):
            compose = parse_yaml(compose)

        dump_yaml(config.TMP_COMPOSE, compose)
        compose = config.TMP_COMPOSE

        proc = await asyncio.create_subprocess_exec("docker", "stack", "deploy", "--compose-file", compose, "walkoff",
                                                    stderr=asyncio.subprocess.PIPE, stdout=asyncio.subprocess.PIPE)
        await log_proc_output(proc)

        if proc.returncode:
            raise OSError
        else:
            return True

    except Exception as e:
        logger.info("Failed deploying, waiting to try again...")
        raise e


@retry(stop=stop_after_attempt(10), wait=wait_exponential(min=1, max=10))
async def rm_stack(stack_name):
    try:
        logger.info("Removing Walkoff stack and related artifacts...")

        proc = await asyncio.create_subprocess_exec("docker", "stack", "rm", stack_name, stderr=asyncio.subprocess.PIPE,
                                                    stdout=asyncio.subprocess.PIPE)

        await log_proc_output(proc)

        if proc.returncode:
            raise OSError
        else:
            return proc

    except Exception as e:
        logger.info("Failed to fully remove stack, waiting to try again...")
        raise e


async def build_image(docker_client, repo, dockerfile, context_dir, dockerignore):
    logger.info(f"Building {repo} with {dockerfile} in {context_dir}")

    with docker_context(Path(context_dir), dockerignore=dockerignore) as context:
        log_stream = await docker_client.images.build(fileobj=context, tag=repo, rm=True,
                                                      forcerm=True, pull=True, stream=True,
                                                      path_dockerfile=dockerfile,
                                                      encoding="application/x-tar")

    await stream_docker_log(log_stream)

async def pull_image(docker_client, repo):
    logger.info(f"Pulling image {repo}")

    try:
        await docker_client.images.pull(repo)
        logger.info(f"Pulled image {repo}.")
        return True
    except aiodocker.exceptions.DockerError as e:
        logger.exception(f"Failed to pull image: {e}")
        return False


async def push_image(docker_client, repo):
    logger.info(f"Pushing image {repo}.")

    try:
        await docker_client.images.push(repo)
        # await stream_docker_log(log_stream)
        logger.info(f"Pushed image {repo}.")
        return True
    except aiodocker.exceptions.DockerError as e:
        logger.exception(f"Failed to push image: {e}")
        return False

async def image_exists(docker_client, repo):
    try:
        await docker_client.images.inspect(repo)
        logger.info(f"Image exists {repo}.")
        return True
    except aiodocker.exceptions.DockerError as e:
        logger.info(f"Image doesnt exist {repo}.")
        return False

async def force_service_update(docker_client, service_name, image):
    logger.info(f"Forcing service update for {service_name}...")
    await update_service(docker_client, service_name, image=image, force=True)

    await asyncio.sleep(3)

    logger.info(f"Scaling {service_name} to 0...")
    await update_service(docker_client, service_name, image=image, force=True, mode={"replicated": {"Replicas": 0}})

    replicas = 1
    while replicas > 0:
        replicas = (await get_replicas(docker_client, service_name))['running']
        await asyncio.sleep(2)

    logger.info(f"Scaling {service_name} back to 1...")
    await update_service(docker_client, service_name, image=image, force=True, mode={"replicated": {"Replicas": 1}})

    while replicas < 1:
        replicas = (await get_replicas(docker_client, service_name))['running']
        await asyncio.sleep(2)

    logger.info(f"Forced service update for {service_name}.")


class Bootloader:
    """ A class to hold the logic for each of the possible commands. This follows the dispatch pattern we us in app_base
        for calling actions in apps. The pattern as applied to the CLI follows close to this example:
        https://chase-seibert.github.io/blog/2014/03/21/python-multilevel-argparse.html#
    """

    def __init__(self, session=None, docker_client=None):
        self.session: aiohttp.ClientSession = session
        self.docker_client: aiodocker.Docker = docker_client
        with open(".dockerignore") as f:
            self.dockerignore = [line.strip() for line in f.readlines()]

    @staticmethod
    async def run():
        """ Landing pad to launch primary command and do whatever async init the bootloader needs. """
        # TODO: fill in the helps, and further develop cli with the end user in mind
        commands = {"up", "down", "refresh"}
        parser = argparse.ArgumentParser()
        parser.add_argument("command", choices=commands)
        parser.add_argument("args", nargs=argparse.REMAINDER)

        logger.setLevel("DEBUG")
        docker_logger.setLevel("DEBUG")

        # Parse out the command
        args = parser.parse_args(sys.argv[1:2])

        async with aiohttp.ClientSession() as session, connect_to_aiodocker() as docker_client:
            bootloader = Bootloader(session, docker_client)

            if hasattr(bootloader, args.command):
                await getattr(bootloader, args.command)()
            else:
                logger.error("Invalid command.")
                # TODO: Pipe this through the logger. print_help() accepts a file kwarg that we can use to do this
                parser.print_help()

    @retry(stop=stop_after_attempt(10), wait=wait_exponential(min=1, max=10))
    async def wait_for_registry(self):
        try:
            async with self.session.get(f"http://{static.REGISTRY_SERVICE}:5000") as resp:
                if resp.status == 200:
                    return True
                else:
                    raise ConnectionError
        except Exception as e:
            logger.info("Registry not available yet, waiting to try again...")
            raise e

    @retry(stop=stop_after_attempt(10), wait=wait_exponential(min=1, max=10))
    async def wait_for_minio(self):
        try:
            async with self.session.get(f"http://{config.MINIO}/minio/health/ready") as resp:
                if resp.status == 200:
                    return True
                else:
                    raise ConnectionError
        except Exception as e:
            logger.info("Minio not available yet, waiting to try again...")
            raise e

    async def up(self):

        # Set up a subcommand parser
        parser = argparse.ArgumentParser(description="Bring the WALKOFF stack up and initialize it")
        parser.add_argument("-b", "--build", action="store_true",
                            help="Builds and pushes all WALKOFF components to local registry.")
        parser.add_argument("-d", "--debug", action="store_true",
                            help="Set log level to debug.")
        parser.add_argument("-y", "--yes", action="store_true",
                            help="Skips all verification questions.")
        parser.add_argument("-r", "--resources", action="store_true",
                            help="Only runs the resource services.")
        parser.add_argument("-o", "--offline", action="store_true",
                            help="Runs WALKOFF offline")

        # Parse out the command
        args = parser.parse_args(sys.argv[2:])

        debug_pw = None
        debug_pw_encryption = None
        if args.debug:
            logger.setLevel("DEBUG")
            docker_logger.setLevel("DEBUG")

            if args.yes or await are_you_sure(
                    "You specified -d/--debug, which will use 'walkoff123456' as the password for all "
                    "resources, This should be used for debug only. "
                    "(Choose 'no' to use randomly generated passwords.)"):
                debug_pw = b"walkoff123456"
                debug_pw_encryption = b"walkoff123456789987654321walkoff"

        # Create Walkoff encryption key
        await create_encryption_key(self.docker_client, static.ENCRYPTION_KEY, debug_pw_encryption)

        # Create internal user key
        await create_encryption_key(self.docker_client, static.INTERNAL_KEY, debug_pw)

        # Create Minio secret key
        await create_encryption_key(self.docker_client, static.MINIO_ACCESS_KEY, b"walkoff123456")
        await create_encryption_key(self.docker_client, static.MINIO_SECRET_KEY, debug_pw)

        # Create Mongo user password
        await create_encryption_key(self.docker_client, static.MONGO_KEY, debug_pw)

        # Create Redis key
        await create_encryption_key(self.docker_client, static.REDIS_KEY, debug_pw)

        # Create volumes
        logger.info("Creating volumes for persisting (registry, minio, mongo, portainer)...")
        for volume in volume_names:
            await self.docker_client.volumes.create({"name": volume})

        # Bring up the base compose with the registry
        base_compose = parse_yaml(config.BASE_COMPOSE)

        for service_name, service in base_compose["services"].items():
            if args.offline:
                if not await image_exists(self.docker_client, service["image"]):
                    if not await pull_image(self.docker_client, service["image"]):
                        logger.info("Failed to pull requisite images, aborting deployment. "
                                    "Please use the 'down' command to clean up. ")
                        return
            else:
                if not await pull_image(self.docker_client, service["image"]):
                    logger.info("Failed to pull requisite images, aborting deployment. "
                                "Please use the 'down' command to clean up. ")
                    return

        logger.info("Deploying base services (registry, minio, mongo, portainer, redis)...")
        await deploy_compose(base_compose)

        if args.resources:
            return

        await self.wait_for_registry()

        # Merge the base, walkoff, and app composes
        app_composes = generate_app_composes()
        walkoff_compose = parse_yaml(config.WALKOFF_COMPOSE)
        merged_compose = merge_composes(walkoff_compose, app_composes)

        dump_yaml(config.TMP_COMPOSE, merged_compose)

        if args.build:
            walkoff_app_sdk = walkoff_compose["services"]["app_sdk"]
            await build_image(self.docker_client, walkoff_app_sdk["image"],
                              walkoff_app_sdk["build"]["dockerfile"],
                              walkoff_app_sdk["build"]["context"],
                              self.dockerignore)
            await push_image(self.docker_client, walkoff_app_sdk["image"])

            builders = []
            pushers = []

            for service_name, service in walkoff_compose["services"].items():
                if "build" in service:
                    build_func = build_image(self.docker_client, service["image"],
                                             service["build"]["dockerfile"],
                                             service["build"]["context"],
                                             self.dockerignore)
                    push_func = push_image(self.docker_client, service["image"])
                    if args.debug:
                        await build_func
                        await push_func
                    else:
                        builders.append(build_func)
                        pushers.append(push_func)

            if not args.debug:
                logger.info("Building Docker images asynchronously, this could take some time...")
                await asyncio.gather(*builders)
                logger.info("Build process complete.")
                logger.info("Pushing Docker images asynchronously, this could take some time...")
                await asyncio.gather(*pushers)
                logger.info("Push process complete.")

        await self.wait_for_minio()
        # await self.push_to_minio()

        logger.info("Deploying Walkoff stack...")

        return_code = await deploy_compose(merged_compose)

        logger.info("Walkoff stack deployed, it may take a little time to converge. \n"
                    "Use 'docker stack services walkoff' to check on Walkoff services. \n"
                    "Web interface should be available at 'https://127.0.0.1:8080' once walkoff_resource_nginx is up.")

        return return_code

    async def down(self):

        # Set up a subcommand parser
        parser = argparse.ArgumentParser(description="Remove the WALKOFF stack and optionally related artifacts.")
        parser.add_argument("-c", "--clean", action="store_true",
                            help="Removes all encryption keys, volumes, data.")
        parser.add_argument("-d", "--debug", action="store_true",
                            help="Set log level to debug.")
        parser.add_argument("-y", "--yes", action="store_true",
                            help="Skips all verification questions.")

        # Parse out the command
        args = parser.parse_args(sys.argv[2:])

        if args.debug:
            logger.setLevel("DEBUG")
            docker_logger.setLevel("DEBUG")

        proc = await rm_stack("walkoff")

        # if not args.skipnetwork:
        #     logger.info("Waiting for containers to exit and network to be removed...")
        #     await exponential_wait(check_for_network, [self.docker_client], "Network walkoff_default still exists")

        if args.clean:
            if args.yes or await are_you_sure("Are you sure you want to remove all WALKOFF data? This will remove "
                                              "all of WALKOFF's docker secrets, docker volumes, and data for "
                                              "walkoff_resource services,"):

                for key in key_names:
                    await delete_encryption_key(self.docker_client, key)

                for volume in volume_names:
                    await delete_volume(self.docker_client, volume)

        logger.info("Walkoff stack removed, it may take a few seconds to stop all containers.")

        return proc.returncode

    async def refresh(self):
        parser = argparse.ArgumentParser(description="Rebuild a specific service and force it to update.")
        parser.add_argument("-s", "--service",
                            help="Name of the service to rebuild and update. "
                                 "You can specify a prefix ('walkoff_app' or 'walkoff_core') "
                                 "to rebuild all in that category.")
        parser.add_argument("-y", "--yes", action="store_true",
                            help="Skips all verification questions.")

        args = parser.parse_args(sys.argv[2:])

        compose = parse_yaml(config.TMP_COMPOSE)['services']
        service_yaml = compose.get(args.service)

        if service_yaml:
            if args.yes or await are_you_sure("Forcing a service to update will disrupt any work it is currently "
                                              "doing. It is not yet guaranteed that a service will pick back up "
                                              "where it left off. "):
                if "build" in service_yaml:
                    await build_image(self.docker_client, service_yaml["image"],
                                      service_yaml["build"]["dockerfile"],
                                      service_yaml["build"]["context"],
                                      self.dockerignore)
                    await push_image(self.docker_client, service_yaml["image"])

                service_name = f"walkoff_{args.service}"
                await force_service_update(self.docker_client, service_name, service_yaml["image"])
        else:
            services = list(compose.keys())
            services.sort()
            logger.exception(f"No such service, valid services: {services}.")


if __name__ == "__main__":
    asyncio.run(Bootloader.run())